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Bottlehead Kits => Legacy Kit Products => Quickie => Topic started by: earwaxxer on December 25, 2012, 12:13:08 PM

Title: Quickie as tube buffer...hum
Post by: earwaxxer on December 25, 2012, 12:13:08 PM
It just dawned on me that the humble Quickie may have another function that many may have not adequately considered.

I introduce the Quickie buffer.

I removed said volume controls, due to a volume control that I have on my Crown sub amp. I'm not going to say that its SO much better than having the volume control at max. I dont think so. Although I did have boutique controls in there.  What I DO KNOW, is that the Crown is performing at a much higher level than without said Quickie(s). The bass has improved in specific terms of a more realistic bass response. The frequency of the crossover is not as critical as it was before said buffer. A much fatter more realistic bass. All good. Of course I am using two, but even one is good. Give me another year or so, I will find more tasks for this gem!

Long live the Quickie!!!!
Title: Re: Quickie as tube buffer...hum
Post by: 4krow on December 25, 2012, 12:18:57 PM
Ok smartasp, I believe you. Now I would like to do the same thing, but lower the gain to unity or slightly above. I would keep the volume controls(one for each channel) to use as a balance control. Your thoughts...
Title: Re: Quickie as tube buffer...hum
Post by: earwaxxer on December 25, 2012, 12:31:43 PM
Hey Greg! Merrrrry Christmas - you son of a bitch! sorry- had a few scotches here already - Its Christmas, so I'm allowed.

Good idea as a balance control . I would agree. One Quickie per channel. F**kin awesome. I will admit, sorry Bottlehead, I did make my second one on my own, but who could resist. They were smart, of course, to price it at $99, because it would cost you more to make your own! Anyway.... Shit ya, put the Quickie in service as you see fit. Dual mono? Why not. I'm going to rig mine as balanced at some stage. Very interesting.

Anyway - merry christmas bro! - Eric
Title: Re: Quickie as tube buffer...hum
Post by: earwaxxer on December 25, 2012, 12:44:43 PM
I wanted to upload a pic of my masterpiece but I'm over my 'max'. Doc? You can delete my pics so I can upload more.

peace, love, dope, tubes, (add your own).  - Eric
Title: Re: Quickie as tube buffer...hum
Post by: Chris on December 25, 2012, 01:16:37 PM
haha love it wax... merry christmas to you, and what scotch are/were you imbibing with??
Title: Re: Quickie as tube buffer...hum
Post by: earwaxxer on December 25, 2012, 01:20:31 PM
Hey Chris - nothing fancy just a Glenmorangie. I'm a whore. What can I say!
Title: Re: Quickie as tube buffer...hum
Post by: Chris on December 27, 2012, 02:21:39 PM
Well, Glenmorangie is one fine dram... thats for sure... nothing average about it... Thats how i first heard of them, when living in London and visiting the local pub (as you do!), I asked a great scottish friend of mine what was his fave dram, and the words glenmorangie immediately sang from his mouth.... Also , one of the more smooth and best value scotches out there.. so great choice.
Title: Re: Quickie as tube buffer...hum
Post by: earwaxxer on December 28, 2012, 01:36:18 PM
This is true Chris, but one must consider the environment in which I live. There are, almost literally, guns and booze available for purchase on every street corner. Anyone can pack a concealed weapon without a permit (over 21). Everyplace that sells food sells alcohol in all its various manifestations, Not just beer. The specialty 'Liquor' store supermarkets have every libation on the planet. Great sales and coupons as well! With all of our sunshine and great weather, I can only imagine how much the Russians must drink!
Title: Re: Quickie as tube buffer...hum
Post by: proud indian on December 28, 2012, 02:51:46 PM
I was on Ardbeg last night. ;D

shreekant
Title: Re: Quickie as tube buffer...hum
Post by: earwaxxer on December 28, 2012, 04:25:33 PM
Shreekant - thats some good libation there! I usually dont admit that I am ever under the control (on) of my booze. Denial with a capital 'D'!
Title: Re: Quickie as tube buffer...hum
Post by: proud indian on December 29, 2012, 07:24:20 AM
As a hero member, you are entitled to your opinion on Booze!!!!!!! ;) ;D ;D ;D  New year eve is a few days away and I am having about 40 people over. The T amp takes over for parties with the Lowthers. Yes... it gets very loud and since I am a tube a slut, a 12AT7 holds stage as a buffer. CANNOT have a total SS set up !!!

shreekant :)
Title: Re: Quickie as tube buffer...hum
Post by: earwaxxer on December 29, 2012, 09:16:38 AM
sounds like a great party! - We are going to a party - its probably not going to be anything like yours (squaresville).
Title: Re: Quickie as tube buffer...hum
Post by: Chris on December 29, 2012, 07:55:00 PM
Yes, I know Wax... The selection of just about everything in the States these days is just massive!.. In Seattle, there is a store called "99 bottles", and when you walk in, the entire store is filled to the brim with beers from all over the world... Just guessing, but maybe 1000 different kinds?...  I was amazed, impressed and frustrated all at the same time... I love to try things and learn, but that place would take me forever to sample everything.... Only in America!!! and thats (that's.... for Paul) why we LOVE the place!!!...
Title: Re: Quickie as tube buffer...hum
Post by: proud indian on December 30, 2012, 03:11:51 AM
So much booze....so little time  ::)

shreekant
Title: Re: Quickie as tube buffer...hum
Post by: earwaxxer on January 18, 2013, 03:15:01 PM
Update on the 'new years eve' party. It was actually pretty fun. There is some video available, I have yet to see it, of me dancing to some old MJ songs. If I get it, I will definitely pass it your way. I was pretty lit. In the grove, as we used to say. My wife drove home. All is good.
Title: Re: Quickie as tube buffer...hum
Post by: 4krow on January 18, 2013, 03:58:50 PM
Wait a minute  wate a minite wade a mininight, The quickie as a buffer? could it get closer to that just by changing to a tube with less gain?
Title: Re: Quickie as tube buffer...hum
Post by: earwaxxer on January 18, 2013, 04:28:31 PM
Hey Greg! - I wondered how long it would take for you to chime in! A 'buffer' is not much different than a preamp. Take the volume control out. Or, were you more interested in my new years eve 'escapades'?
Title: Re: Quickie as tube buffer...hum
Post by: 4krow on January 18, 2013, 06:30:55 PM
All I gotta do iz read the front page iffn I wan't ta knoe yer beeswax.

  Now, I think that a buffer will have zero gain as opposed to a pre-amp. I still put volume controls on mine to fine tune the input going to my integrated amp. Sure, it adds cicuitry, but even so I like the results.
Title: Re: Quickie as tube buffer...hum
Post by: Jim R. on January 19, 2013, 04:00:38 AM
Greg,

Have you tried just jumpering out the volume control on the integrated and using it as a straight power amp with the quickie in front of it?  May be worth a try.

-- Jim
Title: Re: Quickie as tube buffer...hum
Post by: earwaxxer on January 19, 2013, 04:07:17 AM
ok true - I guess a preamp and a buffer are different in that a pre has gain, but they both, ideally, 'improve' the sound. Its amazing to me how many ways there are to do thing. With digital, even more possibilities.
Title: Re: Quickie as tube buffer...hum
Post by: 4krow on January 19, 2013, 08:30:30 AM
Jim, I have tried that, but because the sensitivity of my integrated is quite high, I use the volume control on the buffer to adjust input gain if you will. This allows me to have a greater degree of rotation on my amp's volume control. I know, I could have adjusted that within the integrated itself, but this was is more adjustable and immediate..
Title: Re: Quickie as tube buffer...hum
Post by: galyons on January 19, 2013, 09:09:28 AM
Every added component degrades the fidelity.  Pots are some of the worst offenders.  Have you considered reducing the sensitivity of the Quickie or integrated amp with high quality resistors?  A pot is just a variable resistor.  Cheap pots are more expensive than good resistors. Every pot eliminated is, generally, a good thing. Just measure the Quickie's or the integrated amp's pot resistance at the desired level and replace with similar value high quality discrete resistors.

Extraneous pots would be like adding soda pop to a barrel strength single malt instead of a splash of pure water!!!!

Cheers,
Geary
Title: Re: Quickie as tube buffer...hum
Post by: 4krow on January 19, 2013, 10:11:46 AM
I like soda pop, and so I am sticking with this arrangement....for now. I have beat the OCD gene into submission. " walk away very slowly, and don't turn your back"
Title: Re: Quickie as tube buffer...hum
Post by: proud indian on January 20, 2013, 01:52:02 AM


Extraneous pots would be like adding soda pop to a barrel strength single malt instead of a splash of pure water!!!!

Cheers,
Geary

Well, I got one better. There was this guy at a party who insisted on having Glenlivet with tonic water!!! Maybe he thought it was Gin. :o :o :o
Title: Re: Quickie as tube buffer...hum
Post by: earwaxxer on January 20, 2013, 04:26:25 AM
'A pot in your hand, is worth two in you Scotch'....
Title: Re: Quickie as tube buffer...hum
Post by: 4krow on February 27, 2013, 11:01:34 AM
Ok, back to topic. Quickie as a buffer. I'm hard headed when it comes leaving the volume control in the Quickie, but I am asking how might it be possible to lower the gain of the Quickie.
Title: Re: Quickie as tube buffer...hum
Post by: underdawg on February 27, 2013, 11:48:21 AM
I would think the easiest from electronics perspective is add a resistor at the rca out or in to step the gain down.You can try input if you device is 2 plus volts otherwise put on the rca outs. Just my 2 cents. 8)
Title: Re: Quickie as tube buffer...hum
Post by: 4krow on February 27, 2013, 12:11:03 PM
No doubt, adding a resistor to the input would do the trick, but I am thinking there is a way to decrease the gain of the circuit itself, perhaps adjusting filament voltage? I don't know
Title: Re: Quickie as tube buffer...hum
Post by: Paul Joppa on February 27, 2013, 12:30:33 PM
The gain of the tube is set by its internal geometry. You can however load it down - the stock plate resistor drops the gain 6dB from a very high load (PJCCS or plate choke). Using an even smaller plate resistor than the stock 4K would do the following:

1) increase distortion

2) reduce peak output voltage

3) reduce gain

4) reduce output impedance

5) increase plate current (i.e. reduce battery life)

The distortion and plate current effects are not large, so there's no real reason not to try them. The peak output will go down with the gain, so it's probably not an issue either - if you want very low gain, you probably don't need very much output! Worst case you'll have to restore the original configuration.
Title: Re: Quickie as tube buffer...hum
Post by: 4krow on February 28, 2013, 04:54:31 AM
Paul, THAT was the question I was trying to ask, thank you. I just don't have enough knowledge to know how to phrase my questions sometimes. I will consider using your answer when the new Q 1.1 arrives. Thanks