Preamp that saturates vocals/Instrument on loud passages

Hello,
i need a preamp that drives vocals and Instruments in a nice harmonic saturation on loud parts.
Does anybody have a recommendation for me? Of course it should be adjustable for adjusting th accurate point.

Maybe MILA of NYD?
Any experience with other gear...avalon, manley tube di or some DIY things?

best regards
aaron

stick this to the output of your preamp and crank the gain. 

thank you noulou.
I search for a kind of distortion with triodes or field-effect transistors that produces more even harmonics and lowers the high frequencys.
ok you are showing up a transformator... i do not know if it can make the distortion typ i search for. i would need listening to it. do you have an audio sample? 
would your graphic work with an edcore wsm 15k/600? The hi resistor: should there be a 1k poti for adjusting the distortion?
Is "LO" the cold and arrow the hot signal?
Maybe it is worth a try

thanks

Look at the Collins 6Q-1 or the RCA BA-2C.  Both lack loop NFB, and in my (hands on) experience you only get what you speak of with little or no loop NFB.  Another platform of note is the Gates SA-70.  Almost all other classic tube circuits use 25+ dB of loop NFB, and go too quickly from clean to clipping.  These 3 types exhibit a longer distortion knee.   Modify the Collins to have interstage gain, do the BA-2 or SA-70 with 6SJ7's or 6C5's if the grid cap 6J7's bug you.  Leave the NFB out of the Gates altogether, or make it switchable.  I think there's a NewYorkDave MILA or OneBottle variant without loop NFB, which would be worth comparing.  

very interesting! You make me brood  but it is not easy getting all these old parts... isn´t there a modern circuit that make such a distortion possible?
I didnt took a look on NYD´s bottle but it was sayed in one of your threads... is it an enhanced design of one of these three circuits?
thanks aaron

What old parts?  The tubes are all very common, use any transformers you want that meet the basic requirements.  Nothing oddball here.  The RCA output is the trickiest; the Gates and Collins outputs could both be done with Edcors, in theory. 

The output attenuator shown above does not address your request at all, in my opinion.  It sounds like you want a long soft knee like heard in countless rock and roll records of the '50's.  The Little Richard vocal distortion sound, etc. 

yes!! thats exactly the sound i mean! 
the pics looked like you have used original transformers but i read not all the text yet.
you mean this circuit?
http://img232.imageshack.us/img232/461/gatestubeconsolemicprea.jpg
I have lying around some 15k/600 Edcors maybe good for the output. Do you know if i can modify those for the input too or do i need a different edcore typ?
Thanks
Aaron

Very similar to this, i think this is what people refer to as the NYD without negative feedback.

The above drawing had an earlier variant with 12AV7, but it was the same idea: one bottle with no NFB. Soft knee distortion that follows the tube chart curves.

MILA-1 or the original one bottle preamps are bad choices for any kind of soft tubey distortions. It's almost difficult to hit even 1% THD. In any general use case they are so clean you won't know it's a tube preamp unless someone tells you. They lack distortion, but exhibit other desirable characteristics of tube preamps. Namely high headroom, and high speed (transients don't get any more clear than this).

My apologies. I misread what you were looking for. 

I probably got too excited by my discovery of this simple attenuator circuit.  After sticking this really simple 1k gain pot at the outputs of various preamps, I was amazed by the range of possibilities achieved by subtle tweakings.

Now, the suggestions of no-feedback tube circuits make me quite curious too!
Until now, I have always been dependant of plugins for that soft knee distorted sound.  :-[

Yes this is very interesting. Why aren´t those negative feedback preamps common? Many software plugins try to copy those sounds.
but i did not heard of NFB till now. wow i am so interested reading about it. Is this ciruit above an adapted circuit of "NYD-One-Bottle" with no feedback? do you have the original for comparing? i hardly try to understand the theory of "NFB". Wow!

I'm really interested into this too because,, in a previous thread about getting more saturation out of the NYD, no one actually mention the fact that preamps with negative feedback are more kind of ''clean'' preamps with lots of clean headroom. 

Here's the original NYD one bottle: 

And the 12av7 version without negative feedback..

I can sleep with that   tomorrow i will studie the parts...
thank you very much.

Same Gates thread, I posted all the SA-70 variants.  I'm not real thrilled with the Gates circuit you found.  You need some other input, anything used by anyone in any NYDave build will work.  Buy expensive, buy cheap, manufacturer of your choice (other than Edcor).  Original iron would be great, but if you went looking you'd hunt for a long long time.  I have some appropriate non-exact vintage iron languishing in the black market, but that's another story.  The type of circuit is the key to what you are after, and any iron that suits your taste will do the job.  No one builds zero feedback preamps now because absolutely everything has to be right.  And, there's no such thing as day to day repeatability in manufacturing; it's a very organic beast.  You can't build a mass produced product line on these sorts of tolerances these days.  The (good) old stuff built without NFB loops used the absolute best and most expensive parts one could buy at the time, and those circuits generally haven't been produced since WWII and before.  Again, can't build a product line with that mindset today.  The BA-2 is a hold-out in 1950, and the 6Q-1 is a real oddity for 1956 when it went out of production.  The early Sun Records sound went through an RCA 76 series console that was purchased second hand, and used a preamp circuit that dated to 1939.  I'm not sure modern tubes are up to the task, and you definitely can't build a product line on vintage stock.  Not without tolerating the risk of unavailability.  You can build some for yourself, and get enough tubes to select clean and quiet sounding examples, and I think it's worth the effort.  NFB loops even out the majority of noise and gain differences between tubes.  You can stick any working tube in and get pretty much the same result, aside from hair-splitting gearslutz/audiophile observations.  You build without NFB, and you need to select quiet parts and tubes if working with quiet sources.  If Little Richard shows up, it don't matter!

skip building a whole new box, just put a small nickel core transformer on the output and you will get the exact sound you are after, i hope.

works for me.

pultec meq type amp with a evilbay flavor of the month Ni xfmr.
.

Hi CJ,
i can not belief it but it is worth a try.
I just found the JS-3004N (30mA)from James audio. It has nickel core.
If if there are audible differences between this way and the no feedback preamp circuit. what would be the audible difference?

i have a meq power pcb lying around here. do i need to stuff it complete just with the nickel xfmr on the output should i put the ni xfmr after the regular edcor or lundahl
on the pultec power pcb? Maybe i did not understand it correct with the meq pcb and you mean an other thing..  ???
thanks

hotbaby said:

Any experience with other gear...avalon, manley tube di or some DIY things?

Click to expand...

If you need something cheap and simple try Hamptone HJFP with attenuator Noulou showed. For testing you can make only one p2p stage, add output transformer with 1k pot, feed it with line signal and see how you like it.

Miha

cj was joking hotbaby.

i read allot of threads of CJ and wondered everytime about his dry sense of humour