The Official Guide to Converting your Quickie for Headphone Use

[InfernoSTi]

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

[Paul Joppa]

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.

[sbelyo]

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

[SPaulMac]

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

[kkcinc]

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?

[Wanderer]

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

[bainjs]

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.

[InfernoSTi]

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?

[bainjs]

I misstated the location.  Sorry.  The discussion is in General by Lee Hankins - Headphone Buy of the Year! I received mine last week.

Joel

[InfernoSTi]

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

[bainjs]

If you sign up, the vendor will email you when they are available again.  That's how I got mine.

[Grainger49]

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.

[kkcinc]

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?

[Paul Joppa]

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.)

[kkcinc]

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.