Crack as preamp

J

jimiclow

New member
Hello!
First post. I'm waiting for my crack kit to arrive. I would like to know if I could use the crack as a preamp.
Has anybody tried this?
Thank you in advance.
 
Yes it will work fine as a line level preamp. Of course you won't have the ability to switch sources except by plugging and unplugging cables and you would need an adapter to plug the amp into the headphone jack.
 
Thank you very much for the reply Doc.
So you mean that there would be no modification or addition of parts involved?
 
You will likely throw away a lot of gain in a chain of amps that uses the Crack as a preamp. Take a look at various discussions of "gain structure" by Paul Joppa among many others. Throwing away gain is generally not a good idea.
 
grufti said:
You will likely throw away a lot of gain in a chain of amps that uses the Crack as a preamp. Take a look at various discussions of "gain structure" by Paul Joppa among many others. Throwing away gain is generally not a good idea.
Click to expand...

Gain is about 15dB. Rule of thumb is about 10dB for a line stage. So it's not that far off, actually pretty close to the original Foreplay. I think the output jack and lack of selectable inputs are the only real deterrents.
 
That really leaves just the lack of selectable inputs as a deterrent. Three dollars worth of HOSA cable takes care of the connector issue, if you want to be cheap.

http://www.google.com/products/catalog?hl=en&sugexp=llsin&gs_nf=1&tok=x_5nE6esEeu1SFr6wcNoIA&cp=8&gs_id=ej&xhr=t&q=trs+6.3+mm&safe=off&biw=1333&bih=1052&bav=on.2,or.r_gc.r_pw.r_cp.r_qf.,cf.osb&um=1&ie=UTF-8&tbm=shop&cid=11057247404590733065&sa=X&ei=0rZZT9OMGMbaiQKJz_ioCw&sqi=2&ved=0CEkQ8wIwBQ


I have swapped out the original tubes in my Crack build and forgot that the original configuration has a lot less gain.
 
Ok, couldn't stand it any longer. Connected my Crack to my monoblocks tonight. Very nice sounding. Damn, now I'm going have to build a tube preamp. That means more tube rolling, upgrades and on and on. Will it ever stop?
 
Or if you want to use your own favorite interconnect cables:
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=090-314&utm_source=googleps
 
Thanks again for all the responses.
Actually, I plan of using the Crack with the Decware Taboo.
Can't wait for the Crack to arrive..
 
In that case you are going to want a fair amount of gain from your preamp. You might very well be hitting a home run with that pairing. Buy the Speedball ... consider a very good 5998 ... wow!
 
So I had to try it.  Made up a cable from some Kimber speaker cable.  Hooked the Crack up to the little SS amp upstairs.  I really, love Crack.  Especially Speedballing.....
 
Would anyone here be able to offer an opinion about using a speedball crack as a preamp for the Paramounts?  I'm interested in if the output/input impedence is compatible between the two.
 
Yes, Crack can work. It was the thing that inspired our past year's research in low output impedance preamp circuits. It's more or less an original Foreplay circuit but with a bigass cathode follower and lower output impedance.

In preamp comparisons we did the Crack was not quite as good sounding as a modded Crack using the 6080 as a voltage amp rather than a CF. That was not quite as good as using a pair of 7233s as the VA. That was not quite as good as using 6EW7s with the big half shunt regulating the small half (hmm or is that the other way around? - can't recall off hand), and to my ear the 300B preamp is at a different level of the game than any of those. All of these had output impedance of 500 ohms or less, and no output transformers.
 
Now I have to build a Foreplay or Stereomour.  The Crack sounds fine in my heaphone/spare room system.  What do they call that drug that leads to others?
 
It's a "Gateway" drug.  I suspect that is what the Quickie is.  At least it worked that way for me.  Seemed innocent enough at first.  Then it was Foreplay, SEX, Paramours, Crack, Seduction, and now I'm on to Paramounts and a second SEX.  I'd find a 12-step program if I really wanted to quit, but I don't.

 
porcupunctis said:
It's a "Gateway" drug.  I suspect that is what the Quickie is.  At least it worked that way for me.  Seemed innocent enough at first.  Then it was Foreplay, SEX, Paramours, Crack, Seduction, and now I'm on to Paramounts and a second SEX.  I'd find a 12-step program if I really wanted to quit, but I don't.
Click to expand...

I built Crack, Seductiona and FPIII and stopped there. No amp/amps.  The scary thing is that I already do have a couple pairs of speakers that are easily efficient enough for the amplifiers.  So maybe I should say no amp/amps ... yet.
 
I'm gonna reopen this ancient thread. I'm going to try the Crack as a preamp with a simple 1/4 to RCA cable, but assuming I like it, I will want to wire in. Is the bast place to tap the crack as a preamp at the headphone jack, or might it be best tapped between the tubes? I have the speedball installed.

Thanks
 
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