Bottlehead Forum

Bottlehead Kits => Legacy Kit Products => Quickie => Topic started by: Doc B. on October 01, 2009, 11:13:14 AM

Title: The Official Guide to Converting your Quickie for Headphone Use
Post by: Doc B. on October 01, 2009, 11:13:14 AM
       
    Here is the guide to modding your Quickie for use with high impedance headphones, courtesy of Caucasian Blackplate:

OK, since there have been quite a few questions circulating, I thought I would toss up the guide on how to convert your Quickie to headphone use.

    You will need:
    2 Speco T-7010 transformers
    1 headphone jack
    heatshrink tubing or electrical tape


    Step 1 (Preparing the Specos):
    Cut off the yellow, orange, blue, and gray wires from the Speco at the bobbin of the transformer. The black wire on the side of the transformer with the colored wires and the white wire must be trimmed, stripped, and soldered together. Cover the joint with heatshrink or electrical tape.

    (http://lib.store.yahoo.net/lib/yhst-76392764919929/quickie1.jpg)

    Mount the Specos under the D cell battery holders as shown. Be sure the red/brown leads face the tube sockets.

    (http://lib.store.yahoo.net/lib/yhst-76392764919929/quickie2.jpg)

    Solder the brown wires to the cups of each RCA jack. It may help to solder the wire to the cap lead that feeds into the solder cup instead of the solder cup itself. Solder the black wires to the ground buss.

    (http://lib.store.yahoo.net/lib/yhst-76392764919929/quickie3.jpg)

    On the 1/4" jack, run a wire from the terminal closest to the panel to the ground buss of the Quickie. The next terminal back is the "ring", and right is ring, so run the red wire from the right Speco to the ring terminal and solder. Run the red wire from the left Speco to the tip terminal and solder (remember, it's flipped over when you're looking at it, so check the jack colors just to be sure you don't mix them up).

    The jack shown is constructed so that when you plug in headphones the output disconnects. Although it is not installed in this application to perform such a task, be sure to solder the wires to the correct side, or to both sides if you are unsure.

    (http://lib.store.yahoo.net/lib/yhst-76392764919929/quickie4.jpg)

    Sit back and enjoy! For ordering a different transformer, we have the Speco wired as an 8k:500 autoformer.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Wanderer on October 31, 2009, 11:47:52 AM
Quickie headphone with Hammond plate chokes is working here.

Good News/Bad News situation:

Good news -
It works! Got my PCDP hooked in and just got done listening to Yes "Cans and Brahms" (how apropo) and have rest of "Fragile" sluicing past my ears right now.  Quite good sound given the limits of the PCDP. The unit (Memorex if anybody cares) does have a line out.

Phones are AKG 240M. In the past I have tried drivng these with a Total Airhead portable amp and found the sound thin and compressed. The Quckie sounds full with the 240Ms like they sound when driven off a good integrated amp. I do like the sound of the AKG 240M when I can find something able to drive them. 

Bad News -
Not enouph gain. Before the plate chokes the sound level as far to low. With plate chokes things are better but have to have the volume pot full open to get decent level. Seems more sensitive cans are in order.     

What phones are folks finding happiness with? Beyerdynamic KT-880s perhaps?  Any others? Seems high Z phones are not as common as in years past.                 
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Paul Joppa on October 31, 2009, 01:02:07 PM
I think those AKGs are 600 ohms. In that case, try them on the 1K tap instead of 500 ohms - label of the Speco would say 5W instead of 10W. You'll get a little bit more output per volt input that way.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Dr. Toobz on October 31, 2009, 01:09:23 PM
Aren't the AKG's kind of hard to drive, notwithstanding the high impedance? My Beyers are 250ohms and work rather well on the 500 ohm taps, though they also seem a little more sensitive than some AKG's I've tried. Maybe the 1k tap will give you a little more gain, though - let us know, since I've been looking at their new K702 phones but have held off due to this reason.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Wanderer on November 01, 2009, 07:44:44 AM
Experiments with different taps on the transformer will have to wait for a new set of Specos as I trimmed unused leads off close to the windings as per instructions.

Oh well. At least they are cheap.

Any other suggestions on phones that work on a unit set up from the original instructions.

Sennheiser 580/600 have sounded a little closed in/lacking in air/dull when I have heard them in the past (with an X-Cans hybrid amp). Does the Quickie open them up?         
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Paul Birkeland on November 01, 2009, 11:47:04 AM
Aren't the AKG's kind of hard to drive, notwithstanding the high impedance? My Beyers are 250ohms and work rather well on the 500 ohm taps, though they also seem a little more sensitive than some AKG's I've tried. Maybe the 1k tap will give you a little more gain, though - let us know, since I've been looking at their new K702 phones but have held off due to this reason.

The 702's are indeed quite tough to drive, the 600 ohm K240M's are not. 
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Paul Joppa on November 01, 2009, 04:53:09 PM
Now I am really confused.

I did a little searching. Found the "headphone.com" site which seems to have lots of specs. There, I see the AKG240 MKII at 55 ohms (I think the original poster did not have the Mk II). Anyhow there the 240M MkII is spec'd at 91dB SPL/v and the 702 is 105dB/v (at 62 ohms). At the AKG site, there's a (discontinued) 240 Studio (55 ohms, 91dB/mW,  104dB/v), the 240DF (600 ohms, 88dB/mW), and the Mk II (55 ohms, 91dB/mW,  104dB/v). I didn't find any K240M at all.

The Quickie will not drive a low impedance phone very well with the Speco, and my advice about bumping up the output tap applies to 600 ohm phones, not to 60 ohm phones. I'm really lost here...
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Wanderer on November 02, 2009, 05:24:42 AM
Spec for the 240 Monitor here:


http://www.akg.com/site/products/powerslave,id,429,pid,429,nodeid,2,_language,EN,view,specs.html

These were contemporary with the 240DF (diffuse field) and have about the same specs, 600 ohms, 88 db SPL/mW
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Wanderer on November 11, 2009, 05:36:29 AM
I am about to order another pair of Speco xformers to experiment with different taps.

Would there be any issue with adding a second headphone jack to connect to the 1K tap while the 500K tap is still connected to the other? No plans to use them both at once, just to swap back and forth for quick A/B.

Seems to me there would not be an issue, but might as well ask.     
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Len on November 11, 2009, 05:58:35 AM
I am about to order another pair of Speco xformers to experiment with different taps.

Would there be any issue with adding a second headphone jack to connect to the 1K tap while the 500K tap is still connected to the other? No plans to use them both at once, just to swap back and forth for quick A/B.

Seems to me there would not be an issue, but might as well ask.     

I expect you'll get an official answer.

I had thought of that myself, and figured that if no circuit was made unless a headphone was plugged in, then it would be alright. But one can forget down the road and plug headphones into both jacks (I least I could).

I decided to use the input selector switch instead. Using one jack, I think the switch can be used to change taps. Worst case, the hole can be used for a different switch.

I plan on using it as a dedicated headphone amp, so I don't expect a need to switch between sources.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Paul Birkeland on November 11, 2009, 08:35:06 AM
I am about to order another pair of Speco xformers to experiment with different taps.

Would there be any issue with adding a second headphone jack to connect to the 1K tap while the 500K tap is still connected to the other? No plans to use them both at once, just to swap back and forth for quick A/B.

Seems to me there would not be an issue, but might as well ask.     

You could indeed add the second jack, as long as you don't put two pairs of headphones on at once.  You could also use a DPDT switch to select the different taps. 
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Wanderer on November 24, 2009, 01:38:07 PM

You could indeed add the second jack, as long as you don't put two pairs of headphones on at once.  You could also use a DPDT switch to select the different taps. 

Headphone Quickie with AKG 240M: 

Okay, new Specos on board. Per Paul Joppa's suggestion using the "5 watt/1k" taps. Quick back and forth and, yes, the "5 watt" taps are just a jot louder. This with the PCDP line out. I have no idea the output volts from this jack. With the CD of "Kind of Blue" I have just a little volumn control left till things get too loud. Loud enouph for me but perhaps not for a real head-banger.   

 I rigged jacks to both "5 watt" and "10 watt" taps. I will not hook up two sets of phones (How drunk would I have to be to do that? - let's not find out!!). I have cut just ONE hole in my home brew wood base so whichever current tap I wish to use that jack will get mounted.   

So far - SOUNDS GREAT!!! HAPPY HAPPY JOY JOY.       
Title: Old speco T-7010 color codes
Post by: cvandyke on December 01, 2009, 12:59:32 PM
I have an older pair of the Speco T-7010 transformers which were removed from the original Paramours during an upgrade. These older transformers did not have the same color coding as the new production ones. For installing these in my Quickie, I developed the table below and thought this might be useful for other bottleheads with older Speco transformers.

--Chris

{Editted from original post which was badly worded}{Editted again to fix stupid error in table}
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Wanderer on December 01, 2009, 04:47:22 PM
Your chart shows .5 k and/or 1 k cut. Aren't one of those headphone connections? 
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: cvandyke on December 01, 2009, 05:27:24 PM
You're right - that's a stupid mistake. I fixed it in the post above. Thanks.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: cpaul on August 23, 2010, 05:40:23 PM
OK, so the Speco won't work with low impedance phones like my Grado SR60s (35 ohm "normal" impedance)?  So is there something I could do if I choose to purchase a Quickie (ummm, my wife isn't listening is she???)?  I mostly want it as a line amp, but was interested in potentially adding a headphone output.  I'd probably use some switch mechanism to remove the headphone iron when not in use unless there's some reason not to do that.

Thanks all.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Paul Joppa on August 23, 2010, 07:37:11 PM
What you want is an 8K:35 ohm transformer. I'm not aware of any. Here are some ideas:

1) Look for a small 4K:16 or 5K:16 - the turns ratio is right at least, and you might find something acceptable, maybe one of the smaller Hammond 125x series.

2) Somebody like Edcor might make one custom, they seem pretty flexible these days.

3) The new Stereomour output is not currently available separately, but if Doc decides to sell it you can wire it for 8K:32 - I always planned to use it in a revised SEX eventually.

The power level is very low compared to even transistor-radio standards, so a very small transformer will be plenty big enough. The only risk is, many tiny transformers are designed for small portable gear and may have inadequate inductance for good bass.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: vanofmonks on August 24, 2010, 02:38:59 PM
Actually Edcor EM0735 is an 8kct to 250 ohm transformer with a 32 ohm tap.  I had them make it, so the design fee is paid for.  You can check the price for them.  I haven't used them yet mainly because I have been too lazy to figure out how to hook them up.  Is there a way to use these as an autoformer like the speco?  Or should I just connect them like a regular transformer.  I would be willing to donate a pair to someone who has the equipment and ability to optimize their use.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Paul Joppa on August 24, 2010, 07:46:48 PM
The Speco has many taps on the high-impedance primary winding, including one at 500 ohms, so an autoformer is the only way to drive high impedance phones with it. The Edcor you describe has no such limitation, and can easily be used as an ordinary transformer. That's how I would do it.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: cpaul on August 25, 2010, 04:36:32 AM
Thanks for the replies.  I have contacted Edcor about the custom iron, and will research this more.  May just build it without to start, and modify later.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Dr. Toobz on August 25, 2010, 11:38:50 AM
Edcors should work well - I've experimented with their mid-range irons (8k to 8 ohm) with the Quickie circuit, both in series and parallel feed. (For the latter, I used 150H plate chokes and 3.0uF coupling caps). While there is definitely less power at 8 ohms, the Quickie seems to work great with Edcor transformers. An 8k to 250/32 ohms would be quite ideal.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: cpaul on October 24, 2010, 03:31:21 PM
Edcor got back to me about the EM0735.  As of September they were $10.23 each, plus shipping.  I did order the Quickie - still waiting for it to arrive - but haven't decided what to do about the output for headphones.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Doc B. on October 24, 2010, 04:16:41 PM
Quickies have been back ordered due to a snafu in production of the last batch of chassis plates. The replacement plates were completed this weekend and there should be a big stack of Quickies shipping in the coming week.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: cpaul on October 24, 2010, 04:34:39 PM
Thanks for the update, Doc.  I was wondering what the timing would be.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: SPaulMac on March 26, 2011, 10:47:39 AM
I recently completed my Quickie with the headphone conversion and would like to share my experience. Everything went swimmingly until I pulled the Speco transformers from their boxes to find they were almost exactly nothing like those described in the post. Although the boxes were labeled as T7010 transformers, mine were physically smaller, only had two wires on the secondary side, had seven wires on the primary side none of which were .625W and a completely different color code. Worse yet, two wires exited from the last notch in the bobbin leaving me with no idea which should be connected to the signal. While I can follow directions well enough to assemble a kit the finer details of electronics are beyond me and not having found any specifications for this newer version of the T7010 online I was (after a trouble night) left with the brainstorm of measuring the relative resistances between the 10W brown wire and the other wires. Having done this I settled upon the Violet wire as being that labeled as .5W which was the closest value available to the .625W suggested in the original post. If anyone can suggest a better selection than the 10W/0.5W that I settled upon, I'd greatly appreciate your input. In fact, I would enjoy hearing any suggestions on my implementation that might improve the sound of this lovely little amp.

Correct or otherwise, the Quickie has turned into a quite enjoyable little headphone amplifier. While the output is not substantial enough to drive my inefficient AKG K501 to anything above barely acceptable levels, it has proved a wonderful match for the Beyer DT880 (250 Ohm).

If it should be of any help, as best I can determine, this is the color code for the version of the T7010 I received:

Primary

Common: Black, 10W: Brown, 5W: Red, 2.5W: Orange, 1W: Yellow, 0.5W: Violet, 0.25W: Blue

Secondary

Common: Black, 8 Ohm: Red

(http://i893.photobucket.com/albums/ac140/spaulmac/Bottlehead/IMG_0244.jpg)
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Paul Joppa on March 28, 2011, 09:18:46 AM
That news is quite distressing. When we chose the Speco from a field of more than a half dozen candidates, we did so because the transformer we had been using changed without notice, and the new version was quite inferior. If the Speco has changed substantially, we may have to go through that exercise again. Stay tuned ...
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: sbelyo on May 02, 2011, 07:17:44 AM
Actually Edcor EM0735 is an 8kct to 250 ohm transformer with a 32 ohm tap.  I had them make it, so the design fee is paid for.  You can check the price for them.  I haven't used them yet mainly because I have been too lazy to figure out how to hook them up.  Is there a way to use these as an autoformer like the speco?  Or should I just connect them like a regular transformer.  I would be willing to donate a pair to someone who has the equipment and ability to optimize their use.
I just ordered a pair of these.  Now I just have to get a quickie
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Wanderer on May 02, 2011, 10:25:30 AM
That news is quite distressing. When we chose the Speco from a field of more than a half dozen candidates, we did so because the transformer we had been using changed without notice, and the new version was quite inferior. If the Speco has changed substantially, we may have to go through that exercise again. Stay tuned ...

Inquiring minds want to know....

Looking at the S.E.X. page seems the Specos are currently NOT useable. My ones are the "old" style so lucky me!

Are youse guys gonna sell the Stereomour outputs separately for headphone conversion? Would these be a big up from the Specos? Better bass? I would assume they would cost more then the cheapsy old Specos.     
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: InfernoSTi on May 02, 2011, 04:04:07 PM
Where did you order those from?  Do they look like these? http://www.amazon.com/Speco-10W-70V-Line-Transformer/dp/B001MJFB8E/ref=sr_1_1?ie=UTF8&m=A3AFCSA6JU2B0W&s=merchant-items&qid=1304387790&sr=1-1 (http://www.amazon.com/Speco-10W-70V-Line-Transformer/dp/B001MJFB8E/ref=sr_1_1?ie=UTF8&m=A3AFCSA6JU2B0W&s=merchant-items&qid=1304387790&sr=1-1)  I think the specs listed are the same as the old specs but the model number isn't listed. 

John

I recently completed my Quickie with the headphone conversion and would like to share my experience. Everything went swimmingly until I pulled the Speco transformers from their boxes to find they were almost exactly nothing like those described in the post. Although the boxes were labeled as T7010 transformers, mine were physically smaller, only had two wires on the secondary side, had seven wires on the primary side none of which were .625W and a completely different color code. Worse yet, two wires exited from the last notch in the bobbin leaving me with no idea which should be connected to the signal. While I can follow directions well enough to assemble a kit the finer details of electronics are beyond me and not having found any specifications for this newer version of the T7010 online I was (after a trouble night) left with the brainstorm of measuring the relative resistances between the 10W brown wire and the other wires. Having done this I settled upon the Violet wire as being that labeled as .5W which was the closest value available to the .625W suggested in the original post. If anyone can suggest a better selection than the 10W/0.5W that I settled upon, I'd greatly appreciate your input. In fact, I would enjoy hearing any suggestions on my implementation that might improve the sound of this lovely little amp.

Correct or otherwise, the Quickie has turned into a quite enjoyable little headphone amplifier. While the output is not substantial enough to drive my inefficient AKG K501 to anything above barely acceptable levels, it has proved a wonderful match for the Beyer DT880 (250 Ohm).

If it should be of any help, as best I can determine, this is the color code for the version of the T7010 I received:

Primary

Common: Black, 10W: Brown, 5W: Red, 2.5W: Orange, 1W: Yellow, 0.5W: Violet, 0.25W: Blue

Secondary

Common: Black, 8 Ohm: Red

(http://i893.photobucket.com/albums/ac140/spaulmac/Bottlehead/IMG_0244.jpg)

Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: SPaulMac on May 02, 2011, 04:42:20 PM
Hello John,

I purchased mine from Wallco Industrial Electronics. They don't look anything like those in the Amazon photo; are rather generic in construction with a simple electrical tape type wrapping on the winding and in fact have no Speco nor T7010 markings whatsoever. The boxes did have Speco's branding and were sized correctly for the smaller transformers I received, but I'm getting the sinking feeling I may have received cheap substitutes. My fault for discovering Bottlehead so late in the game. :)

Stephen
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: InfernoSTi on May 02, 2011, 05:00:58 PM
Thanks for the additional info, Stephen.  I'm sorry you didn't get quite what you wanted but it sounds like you made the best of the situation!  Excellent work!  Glad to know the parts may still be available...I think I'll order and see what arrives since I have a Quickie that could be a headphone amp if all works out well....

John
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Paul Joppa on May 02, 2011, 05:37:52 PM
Caveat emptor. The picture and the taps on Amazon are correct, but the description says it weighs 5 pounds, shipping weight 11.5 ounces. The original Speco weighs 10.5 ounces, while the cheap crappy one weighs 5 ounces. Who knows which one you'll get? How many people will take the trouble to complain for a measly $6.29? Mounting holes are 2.25" on the original, 1.75" on the small one.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: sbelyo on May 24, 2011, 07:46:18 AM
The edcor trannies are on their way.  Should have them by Thursday.  We're going to set this quickie up for dedicated headphone use.  My 11 y/o son was hooked once I let him solder a few joints on the crack.  He's going to do most of the work, I'll just help him where he gets stuck.

We're going to mount the top plate on a hammond 10x6 steel enclosure and add an alien dac for USB input

I'll take pictures of the edcors when they arrive
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: SPaulMac on November 03, 2011, 01:45:26 PM
I finally got around to ordering the Edcor EM0735 transformers. Now that I have them before me, I have to admit that I probably have no business with a soldering iron in my hands. I have no clue as to how to hook the new transformers into my Quickie's circuit in place of the Specos. I'd imagined something like the signal ground going to both the C.T. and Common taps on the primary and secondary; the signal going to the 8K ohm tap on the primary and the output going from the 250 ohm tap of the secondary to the headphone jack, but I don't really look forward to smoking my little Quickie. I'd be very thankful for any help I can get on the proper wiring procedure for this transformer. The pin assignments for the EM0735 are as follows:

Primary

Pin 1    8K Ohm
Pin 2    Center Tap
Pin 4    8K Ohm

Secondary

Pin 5    250 Ohm
Pin 6    32 Ohm
Pin 8    Common

Thanks,
Stephen
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: kkcinc on November 19, 2011, 05:07:37 PM
Ok, I ordered the transformers to convert to headphone use. Never, ever used headphones before. Need to now with the new baby. Since I am new to this I'd like a budget headphone to start. Are there any sleepers out there? Any recommendations for headphones that work well with quickie for under $100 or better yet under $50? Am I dreaming?
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Wanderer on November 20, 2011, 03:50:41 AM
If you are willing to look for used gear you should be able to get the required high impedance cans in your budget.

As orignally suggested in this thread the transformers are wired for 250 ohm phones.

Look here.

http://www.bottlehead.com/smf/index.php/topic,546.0.html

I am currently using 600 ohm AKG 240Monitor wtih my Quickie. I think they sound fine but others my want a more sensitive set of cans as mine go just loud enouph for me. PJ suggested a different wiring for 600 ohm cans - see above.  

My AKGs are from Ebay and were sub-$100 a couple years back. Don't recall exact price.  

Kevin R-M
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: bainjs on November 20, 2011, 04:52:35 AM
The MB Quart 400's are available again.   Check the discussion in Headphones for more info.  They are 300 ohm units. Great sound and comfortable.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: InfernoSTi on November 20, 2011, 04:55:53 AM
The MB Quart 400's are available again.   Check the discussion in Headphones for more info.  They are 300 ohm units. Great sound and comfortable.

Where are they available, please?
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: bainjs on November 20, 2011, 05:04:02 AM
I misstated the location.  Sorry.  The discussion is in General by Lee Hankins - Headphone Buy of the Year! I received mine last week.

Joel
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: InfernoSTi on November 20, 2011, 05:36:34 AM
I misstated the location.  Sorry.  The discussion is in General by Lee Hankins - Headphone Buy of the Year! I received mine last week.

Joel

I think they are out of stock again....good to know they come back from time to time, however.  I have a set and was hoping to purchase a second as a gift for a friend.

John
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: bainjs on November 20, 2011, 05:44:18 AM
If you sign up, the vendor will email you when they are available again.  That's how I got mine.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Grainger49 on November 20, 2011, 07:12:53 AM
The MB Quart 400's are available again.   Check the discussion in Headphones for more info.  They are 300 ohm units. Great sound and comfortable.

Where are they available, please?

I think that when you find the thread there are links to several ebay auctions.  The seller should have a new auction up for them.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: kkcinc on November 22, 2011, 03:55:28 PM
I got my specos today. They are the cheap ones that SPaulMac got. I am still going to try to make it work. If I wire it up exactly the way he did it will be 10w/.5w instead of 10w/.625w feeding 60ohm cans. Question is, what wiring would work better with 60ohm headphones? I really want to try to make this work. Secondary is red 8ohm only and black 0. Primary is black common, brown 10w, red 5w, orange 2.5w, yellow 1w, violet 0.5w, blue 0.25w. Any suggestions on the wiring, other than getting new transformers?
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Paul Joppa on November 22, 2011, 05:51:48 PM
For cans 45 ohms to about 200 ohms, the best available option based on the turns ratios would be the highest impedance (0.25 watt, which is blue on my sample, and 600 ohms DC resistance to black=ground) to the preamp, and the lowest impedance (10 watt, which is brown on my my sample and 42 ohms to black=ground) to the headphone. Check the DC resistances to be sure you have the correct taps.

For cans below 45 ohms, use the 8 ohm secondary, and try different primaries - 0.25W, 0.5W, and 1W.

In both cases, listen for a lack of treble and/or bass. It might be worth changing these taps if one problem predominates over the other. You may find you have to choose between higher signal and better spectral balance, if your cans are not very sensitive.

I have not done a detailed study of this transformer, just measured the turns ratios so far. They seem to be as advertised (my earlier measurement of the 8-ohm tap was in error, or at least I got a different number tonight - and the new number agrees with the labeling.)
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: kkcinc on November 23, 2011, 12:20:52 PM
Thanks. The thing sounds fantastic using the .25w wiring. These are the cans, Audio-Technica ATHM40FS. I am not missing any range and no range is over emphasized. Volume is good. Normal listening is done at 3/4 of the volume pot. For me the cheaper Speco's are a happy accident. I highly recommend this mod and these phones for the budget conscious people.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: bainjs on November 23, 2011, 01:42:07 PM
I tried wiring the new version of the speco 7010 with mixed results and have confused myself thoroughly.   

Would it be possible for someone to give me the correct wiring for a set of 300 ohm headphones?

  I need basic instructions like "blue goes to input jack, red on secondary side goes to..." and so on.  Which colors do you now tie together since there is no white wire any longer?

Thanks
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: bainjs on November 23, 2011, 03:14:15 PM
After looking at a photo of the old speco, it looks like the white is now the red on the secondary side.  Is that correct?  And would it still go to the black common on the other side?

Based on Paul's last explanation, will the blue go to the input and the red to the headphone jack?  Would the black on the secondary side go to ground?

Am I close?

Thanks
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Paul Joppa on November 23, 2011, 07:20:49 PM
This is excellent news - thanks for posting it! I'll try to find some time to measure the transformer more carefully, since it appears to be worthwhile after all, at least in this application.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: kkcinc on November 24, 2011, 03:17:22 AM
I tried wiring the new version of the speco 7010 with mixed results and have confused myself thoroughly.   

Would it be possible for someone to give me the correct wiring for a set of 300 ohm headphones?

  I need basic instructions like "blue goes to input jack, red on secondary side goes to..." and so on.  Which colors do you now tie together since there is no white wire any longer?

Thanks

If you look at SPaulMac's picture and description on page 2 of this thread, that is the one you would want to follow for 300 ohm cans. I think. Brown wire goes to headphone jack right to ring left to tip and make a wire from ground of the headphone jack to the the grounding bus wire on the quickie. Tie red 8 ohm wire to black common wire on the other side of the transformer. Solder the black wire (labeled 0 on the same side as the red 8 ohm wire ) to the ground bus wire of the quickie. Solder the violet wire to each of the output jack solder cups. Tape off all other leads. Should work fine.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: kkcinc on November 24, 2011, 03:28:29 AM
This is excellent news - thanks for posting it! I'll try to find some time to measure the transformer more carefully, since it appears to be worthwhile after all, at least in this application.
Thank you for the help. I had a chance to listen to two more albums last night. The 60 ohm cans work fine on the .25w tap plenty of deep bass and detailed highs. After further review, it might be missing a slight bit of lower mid-range and upper low-range. The cans could just be flatter than the mid-range heavy speakers that I am used to. I have no reference for the headphones, since they are brand new. Overall I am very happy.
Title: First draft of wiring scheme
Post by: Paul Joppa on November 24, 2011, 11:34:38 AM
Here is a first draft of wiring for the two versions of the Speco T-7010 output transformer. This is for the stock setup (not optimized for choke or PJCCS loads). I'll update it when I have done some more measurements and analysis.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: vanofmonks on November 24, 2011, 12:19:38 PM
Hi just saw this and this is a reply to another question:


I commissioned this model originally, and it was confusing when I first saw it, but it was designed as an 8k winding that they put a CT in.  So for parafeed pin 1-4 is 8K  It is similar to all their other line output transformers in that it is push pull, but can be used as parafeed out.  They stated it should have about 15h inductance for what it is worth.  I have 10, but still have been to lazy to wire them in by quickie.  Hope this helps.


I finally got around to ordering the Edcor EM0735 transformers. Now that I have them before me, I have to admit that I probably have no business with a soldering iron in my hands. I have no clue as to how to hook the new transformers into my Quickie's circuit in place of the Specos. I'd imagined something like the signal ground going to both the C.T. and Common taps on the primary and secondary; the signal going to the 8K ohm tap on the primary and the output going from the 250 ohm tap of the secondary to the headphone jack, but I don't really look forward to smoking my little Quickie. I'd be very thankful for any help I can get on the proper wiring procedure for this transformer. The pin assignments for the EM0735 are as follows:

Primary

Pin 1    8K Ohm
Pin 2    Center Tap
Pin 4    8K Ohm

Secondary

Pin 5    250 Ohm
Pin 6    32 Ohm
Pin 8    Common

Thanks,
Stephen
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: bainjs on November 27, 2011, 01:42:20 PM
Thank you Paul for the diagram.  It made wiring it up much simpler.  Also, thanks kkinc to your suggestion.  They both worked pretty well, however, I think Paul's version has a tad more volume.

Paul:  Do you think there will be changes if the PJCCS module is installed?  I have one in my Quickie.

Joel

Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Paul Joppa on November 27, 2011, 02:51:09 PM
...
Paul:  Do you think there will be changes if the PJCCS module is installed? ...
Stock or modified, I recommend experimenting with adjacent output taps.

You should always use the lowest-power primary tap for the transformer input. That tap will use the entire winding, and have the most inductance (more turns = more inductance). Unless you hate bass, inductance is your friend!
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: kkcinc on November 29, 2011, 02:42:10 AM
Thank you Paul for the diagram.  It made wiring it up much simpler.  Also, thanks kkinc to your suggestion.  They both worked pretty well, however, I think Paul's version has a tad more volume.

Paul:  Do you think there will be changes if the PJCCS module is installed?  I have one in my Quickie.

Joel


I rewired last night with good results. I originally had the 8 ohm connection wired like the old one with 8ohm tied to common and 0 tied to ground, Now it is exactly as Paul has it in his diagram. Does seem to have more volume. Also, maybe a bit more balanced sound. Tried all adjacent taps as suggested and tried both chokes and pjccs. Blue wires on output and brown wires on headphone jack produce the absolute best sound and most volume for my 60 ohm cans.
Very little difference between chokes and pjccs. Big difference with an amp and floor standing speakers, since the chokes hum. No hum with headphones.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: denti alligator on September 03, 2012, 04:31:47 AM
I've upgraded my SEX with MQ iron. Can I use the old transformers to convert a Quickie to a headphone amp?
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: denti alligator on September 05, 2012, 04:48:57 PM
I've upgraded my SEX with MQ iron. Can I use the old transformers to convert a Quickie to a headphone amp?

Anyone?
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: bainjs on September 05, 2012, 05:42:08 PM
I'm pretty sure they won't work.  You'll need to go with the Speco units as outlined in the instructions.  I believe I paid around $20 plus shipping for the pair. 

Joel

Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Paul Birkeland on September 05, 2012, 06:38:32 PM
Hello Sam,

Which stock SEX iron do you have?  If you have the old Specos, then of course you can.  If you have the OT-2, the step-down ratio will be pretty high.  You can try it as an 8K:32 ohm, but the available voltage at that tap will be pretty small.

-PB
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: denti alligator on September 06, 2012, 03:31:31 AM
Yes, I have the old SEX transformers.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Paul Joppa on September 06, 2012, 05:13:07 PM
You mean, I think, the oldest ones from before the Specos. Your transformers are very similar to the Speco, and should work about equally well.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Jim R. on September 10, 2012, 09:35:32 AM
I believe Sam has the Specos as he has a 2.0 kit and I sold him the mq iron for his upgrade.

Sam, the old transformers have yellow tape around them, correct?  If so, the directions are found earlier back in this topic.

-- Jim
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Wormwood on November 12, 2012, 10:00:11 PM
Being new to this all it's fun and frustrating to read these threads that shift into the pages - Frustrating as I don't know 80% of what is being talked about but fun as I can see ideas being shaped and evolving through a gestalt.

Now my question - would the Head-Quickie mod run AKG Q701? Or is this mod more like a mini Crack?

Was thinking down the track to build one of these for my workpod.


Cheers
Stephen


PS: Doc or site Admin - the pics in the front pages are not linking anymore
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Wanderer on November 13, 2012, 03:04:17 AM
Now my question - would the Head-Quickie mod run AKG Q701? Or is this mod more like a mini Crack?


With the Speco Transformer/Autofomers as orignally specified I doubt you will get much joy.

My experiments with trying lower impedance cans, Sennheiser 497 and Yamaha YHD-1,  did not yield anything listenable.

Different transformers where briefly discussed above. Maybe something would work. 

                         
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Wormwood on March 15, 2013, 02:23:09 AM
Would someone mind running me up a shopping list w/links to the parts I would need to convert my Quickie, please.

I have found the Speco on ebay but the chap doesn't sell outside the States - I am in Australia. As for the other parts... yeah I am a tad lost. If you have any Caps that I should swap out that would be great also.


Cheers,

Stephen
Title: Re: Old speco T-7010 color codes
Post by: mcandmar on March 06, 2014, 11:04:18 AM
I have an older pair of the Speco T-7010 transformers which were removed from the original Paramours during an upgrade. These older transformers did not have the same color coding as the new production ones. For installing these in my Quickie, I developed the table below and thought this might be useful for other bottleheads with older Speco transformers.

--Chris

{Editted from original post which was badly worded}{Editted again to fix stupid error in table}

speco_t7010_colours.gif

Here is a first draft of wiring for the two versions of the Speco T-7010 output transformer. This is for the stock setup (not optimized for choke or PJCCS loads). I'll update it when I have done some more measurements and analysis.

first draft Speco wiring.gif

Re-posting missing images, added images of new and old versions.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: musiciseverything on April 23, 2015, 04:37:51 AM
First of all, thanks to Bottlehead for a great piece of equipment.  It worked right out of the shop without any issues.  I want to convert it for headphone use.  I was confused by all the threads and would appreciate any input regarding the parts.  I have a Quickie 1.1 without the PJCCS (I have the add-on but haven't installed it yet).  Are the following parts the correct ones?
Neutrik NMJ6HC-S 1/4" Stereo Phone Jack Switched
Brand:
Neutrik
| Model: NMJ6HC-S


Speco 10W 70V Line Transformer
by Speco

http://www.amazon.com/Speco-10W-70V-Line-Transformer/dp/B001MJFB8E

Thanks in advance.


Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: mcandmar on April 23, 2015, 11:52:44 AM
Ideally you want the newer version of the Speco transformer, that amazon link shows an image of the older version so i can only assume that is what you will get.   

e.g. here is the new style http://www.ebay.co.uk/itm/Brand-New-Speco-T7010-70V-Line-Transformer-10-5-2-5-1-25-and-0-625-watt-tap-/291423991998?pt=LH_DefaultDomain_0&hash=item43da3938be (http://www.ebay.co.uk/itm/Brand-New-Speco-T7010-70V-Line-Transformer-10-5-2-5-1-25-and-0-625-watt-tap-/291423991998?pt=LH_DefaultDomain_0&hash=item43da3938be)
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: musiciseverything on April 23, 2015, 04:11:18 PM
Thanks for your reply. Does the Neutrik headphone jack look right?
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: mcandmar on April 23, 2015, 04:31:20 PM
Yup should work fine.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: musiciseverything on April 23, 2015, 06:56:32 PM
Thanks. Is there an advantage to using or leaving off the PJCCS circuit. I have many phones but plan on the Senn 600s. Thanks very much for your advice. TG
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: mcandmar on April 24, 2015, 03:05:37 AM
Sonically it should be better than the stock resistor plate load, lower distortion, better frequency response etc.  The chokes will fall somewhere in between the two, i really liked the sound with plate chokes on mine so that is how i left it.

It only takes a couple of minutes to install so there is really only one way to find out for sure ;)
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Wanderer on April 24, 2015, 03:52:42 AM
I use mine as  headphone amp with the older Speco. The chokes or PJCCS are really needed to upgrade the gain for my phones. I prefer the sound with PJCCS. If you have the upgrade kit you should try it.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: musiciseverything on April 24, 2015, 05:01:35 AM
 Thanks, again! You guys have really been helpful. I built a crack headphone amplifier which is absolutely fantastic. I am looking to use the Q 1.1 because it is battery operated and portable. Although I have sennheiser HD 600s,  I also use Sennheiser HD 598. The only issue may be that the impedance is 50 ohms versus the 600s which are 300 ohms. Do you think the upgrade will help or hurt with these other headphones?
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: mcandmar on April 24, 2015, 05:39:18 AM
In theory the headphone mod is more suitable for the high impedance headphones like the 300 ohm HD600/650's.  I have used mine with both the HD650's and low impedance 32 ohm Grados and its the Grados that stay plugged in all the time.

The transformers are only pocket money so just give it a try and see.  There are a couple of different output taps on the transformers you can try and see which sounds the best with your headphones.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: musiciseverything on April 24, 2015, 06:19:25 AM
Excellent advice. Thanks again. TG
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: boulos on June 30, 2015, 04:11:54 PM
Hi,

I have a pair of WE 111c isolation transformers.  Can I use them as output transformers for headphone use for the Quickie? (they're too big so they would have to be mounted to a separate box).

Please find attached their spec sheet.

Thanks!
Boulos
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Paul Birkeland on June 30, 2015, 06:37:45 PM
Hi,

I have a pair of WE 111c isolation transformers.  Can I use them as output transformers for headphone use for the Quickie? (they're too big so they would have to be mounted to a separate box).
They don't quite have the ratio that you'd want for this purpose.

-PB
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: boulos on July 01, 2015, 09:47:31 AM
Is this the case even when the transformers are wired as 600 -> 150 ?

Thanks!
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Paul Birkeland on July 01, 2015, 12:41:26 PM
Is this the case even when the transformers are wired as 600 -> 150 ?

Yes.

-PB
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: boulos on July 01, 2015, 01:59:13 PM
Alright, thanks! :)  I'll find a different use for them.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Paul Birkeland on July 01, 2015, 04:09:57 PM
Alright, thanks! :)  I'll find a different use for them.
You could hang them off the output of your BeePre.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: boulos on July 01, 2015, 04:24:53 PM
You could hang them off the output of your BeePre.

ooh, nice.  I don't have one but I built the one GerryE has.  I can ask if he'd like them.  Would it be 600 -> 600?
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Paul Birkeland on July 01, 2015, 04:27:43 PM
600:600 or 600:150.  On the downside, they will load the output of the BeePre if they are installed, even if nothing is hooked up to them.

-PB
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: cpaul on July 24, 2015, 03:56:44 AM
I've finally decided to convert my Quickie 1 to a headphone amp.  I'm using nothing special for cans and they are low impedance.  Edcor no longer makes the EM0735 (I suppose one could custom order it and pay the setup fee) so I bought a pair of the Specos to wire for 32ohm (they are the new ones and weigh in at 4.75oz).  They were quite cheap so I'll give them a try, but they are VERY small so I have my doubts.  Then I took a quick look this morning and found this:  http://www.mcmelectronics.com/product/555-7120.  It sounds virtually identical to the old Specos, weighs just about 10oz (according to the specs) and costs $4.99.  Any thoughts?  I'll probably order a pair to try out.

In both cases I'll post back if/when I have success. 
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Paul Joppa on July 24, 2015, 06:26:07 AM
Seems unlikely - those dual-voltage (70 and 25v compatible) line transformers usually don't have enough inductance for decent bass. But until someone tries it, we'll never know for sure!
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: cpaul on July 24, 2015, 07:06:57 AM
Thanks, Paul.  Transformers are a big black box to me, and I certainly didn't know that about dual voltage (I don't really understand how a dual voltage would be wound in the first place...).  And frankly, I hadn't even noticed that it was dual voltage.  It came up as 70v and I went straight to the specs.  Now I see that.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: cpaul on July 28, 2015, 05:38:42 PM
Tonight I hooked up the tiny Speco transformers per the wiring diagram on post 65 by mcandmar (thanks!) and had a listen.  Quickie performs reasonably with these transformers.  I don't notice substantial loss of bass, midrange is full and clear, and the high end is certainly good if not quite good.  At the same time nothing is outstanding.  Now, this is with Grado SR60s (old version) and Fostex T50RP, both of which are on the low side of impedance (32ohm and about 60ohm respectively).

I got the best performance using the 0.25W tap as the input (attached to the RCAs) and the brown tap (10W) connected to the headphones.  I tried the recommended 32 ohm wiring per the diagram in post #65, but there seems like there's something wrong with that.  When I inadvertently left out the jack ground, I got a small amount of very hollow sounding audio.  When I put it back in, I got nothing.  Checked and re-checked but found no problems.

As I read the diagram (see image), the ground is pulled off of the transformer BEFORE the headphone output.  Wiring is input to 0.25W tap, common on the multi-tap side tied to the ground on the 8ohm side and that connected to Quickie ground, followed by the output attached to the 8ohm tap  That would seem to be a recipe for no sound output even ignoring what the core is doing to the 8ohm "secondary."

Am I misunderstanding something here?  Anyway, I tried a number of variations on the 32ohm wiring to no avail.  I got little or no sound out each time.  But since I was getting reasonable performance with the brown/50-200ohm wiring, I just went with that.  I may experiment more, but reasonably satisfied with the way it is.  I did try the red and orange taps (5w and 2.5w) and they weren't bad, but not as good as the brown/10W tap.

These Specos cost me less than $6 each plus small amount of shipping.  At that cost, it's well worth experimenting.  And I have a reasonable headphone amp to boot.  I'm new to headphone amps, so not sure I have a good baseline to compare, but it's better than the output of my CD player (and OLD Pioneer PO-M6) which is no doubt op-amp based.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: mcandmar on July 28, 2015, 05:55:50 PM
I found the blue/brown combo worked the best for me too.    The 32ohm wiring is for the old style Specos (large), for the new style (tiny) just ignore the secondary windings.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: cpaul on July 29, 2015, 03:32:20 AM
Thanks, mcandmar.  I'm curious, though, about the diagram even if it's for the "old" version.  The first drawing (where it says "New")  shows wiring for 32ohm cans.  As I read it, it ties together the two black "common" taps, connects that point to ground, and pulls the signal off of the red 8ohm tap (on the secondary).  So it seems the signal would come in via the blue 0.25w tap, go out the common on that side and get tied to ground.  In that configuration, I suppose it could be using the Speco as a true transformer instead of an autoformer?  If that were true, I'd expect to at least hear some output, but I got nothing.  Maybe I'll try that again.

Can anyone confirm that the diagram is correct for 32ohm for the New Speco?  And is it right, then, that it's using the Speco as a transformer?  I have some other configurations I may try out for learning purposes, but I'm happy enough as it is.

Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: Paul Joppa on July 29, 2015, 08:09:01 AM
... Can anyone confirm that the diagram is correct for 32ohm for the New Speco?  And is it right, then, that it's using the Speco as a transformer? ...
Yes, you have correctly described the "new Speco" diagram - though it says "less than 50 ohms" actually. (Calling it 32 ohms led to some misunderstanding of which diagram you meant.)

You should hear something from the labeled 8 ohm secondary, but it will be very low, about 18dB lower than the 10W tap. Suitable for extremely sensitive IEMs, perhaps.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: cpaul on July 29, 2015, 02:41:37 PM
Thx, Paul.  Yes, you're right of course.  It is the <50ohm wiring I was talking about.  Glad I now understand it.  I may try it again b/c I can't figure out why I didn't hear anything.  Cheers.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: cpaul on July 30, 2015, 12:09:09 PM
Back in post 84, I mentioned a similar transformer to the old Speco that's available for $4.99 (http://www.mcmelectronics.com/product/555-7120).  Same specs except it's a dual voltage transformer.  Well, despite PJ's concerns, I went ahead and ordered it and it arrived yesterday so I clipped it together today.

WHOA!  Much better than the new Speco.  Quite a lot of extra bass, and cleaner nicer throughout the (my  :-X) audible spectrum.  I don't know if the high end is any better (my old ears aren't so good up high), but it's still quite good.  So overall it's a big improvement over the current Speco.  I wired it essentially the same, blue/0.625w to the RCA outputs, Brown/10w to the headphones, black to ground.  Wiring is similar to the new Speco, wired as autoformer. 

I can definitely recommend this as a cheap way to a headphone amp.  Ultimately I hope to wire it with a switched jack so I can just leave it in place and still use it as a preamp while I build a 27-based linestage.

Photo of the two transformers (Speco is the smaller):
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: bourbonator on December 02, 2015, 07:15:21 AM
CPaul - do you still stand by the recommendation for that transformer?  Sorry, I'm very late to this thread. Looking particularly for what to use for Grado 80 headphones
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: cpaul on December 02, 2015, 08:30:10 AM
Yes, it's far better than the Speco (well, I haven't tried either in a little while as I'm working on some other projects at the moment).  Keep in mind, though, that my Speco is the new one that is quite small, and I haven't tried the older version (which I've never seen available despite the photos that some places are using that makes it look like they're selling the old version).  The older Speco could be better than the ones I use, I just don't know.

In short, unless you know you're getting the larger old Speco, I'd use the one I mentioned.
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: mcandmar on December 30, 2015, 04:10:01 AM
I would be interested to hear what the BH guys think of these as an option https://www.edcorusa.com/pcw10k-7k_300-32 (https://www.edcorusa.com/pcw10k-7k_300-32)

Planning on ordering a pair to experiment with, but thought i would ask in case there is some good reason why they wont work.

Cheers,

Mark
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: AudioDave on January 06, 2016, 02:18:53 AM
CPaul -  Back in post #92 you described how you connected your transformer from mcmelectronics.  Just so I am clear,  are these connections for 32 ohm headphones?
Thanks!
Dave
Title: Re: The Official Guide to Converting your Quickie for Headphone Use
Post by: cpaul on October 09, 2016, 12:12:58 PM
Whoa, Dave, I never got a notification of your post and must not have looked back at this thread.  Sorry about that.  I suppose you've figured it out by now.  In short, I was describing how I wired it for my Grado SR-60 phones (32ohm).   So yes, you are correct.