Tube preamp heads: Gimmick??

[beans-on-toast]

Preamp stands for preliminary amplifier. It's designed to be a source for a downstream amplifier that follows. Requirements are both tonal and electrical although cost, footprint and other factors come into play.

Marketing is an important consideration, you have to be able to sell the amp. In that respect, there are no gimmicks, just the product that they want produce.

 

[Taustin Powers]

For my purposes, there are night and day differences. But, you need to play both and make up your own mind.

The tube preamp hybrids that are most of interest to me are those that demonstrate distinct differences when rolling different tubes of the same type through them. Some of the tube driven hybrids are specifically designed to NOT be sensitive to different kinds of tubes. Those tend to be more aligned with your comment.

Edit: here is my preferred backline amp for 5 or 6 years now. I’ve been through several alternatives during that time, including some you mentioned. This one continues to be head shoulders more to my liking. It is the VTBP-201 with a retrofit internal ICEPower 250ASX2 power module. Simply perfect for my needs.

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I used to own that very preamp and run it through a Crown K2 poweramp many moons ago. Loved that setup! Then I foolishly sold the Demeter and got a Jack Read Bass Purity instead. Shouldn’t have done that...

 

[bucephylus]

I used to own that very preamp and run it through a Crown K2 poweramp many moons ago. Loved that setup! Then I foolishly sold the Demeter and got a Jack Read Bass Purity instead. Shouldn’t have done that...

No sweat. That’s how we learn. I’ve got my skeletons / train wrecks in the books. The only mistake is the one you make a second time.

 

[Samatza]

I haven't noticed a direct correlation between tube "mojo" and preamp tube quantity. (My old Alembic F-1X rackmount pre had only one 12AX7 and didn't distort much, the way I used it. But it did seem to add lots of character - as tube-like as any hybrid setup I've tried. Maybe too much sometimes - almost like the real deal, ha ha.)
There does alas seem to be some correlation between "seriousness" of tube preamp section and price. (Most of the hybrids I would be interested to try - Aguilar, Demeter & Jule - run well over $1K new.)

I have also dialled up some nice tones with the F-1X. First I thought it was just me so I asked a few players to dial up a tone on the Eden WT550 and then the Alembic, they both sound nice but different.

Everyone agreed though that the sound has a nice warmth and character, is it the valve in the preamp? I suspect it is, coming from all valve amps to SS to hybrids I think the valve adds something that’s not easily quantifiable but very musical.

 

[Passinwind]

I used to own that very preamp and run it through a Crown K2 poweramp many moons ago. Loved that setup! Then I foolishly sold the Demeter and got a Jack Read Bass Purity instead. Shouldn’t have done that...

I think I actually liked the Purity a little more myself for my own wants and needs, but both are pretty great, and vive la difference.

Loved my K2s BTW.

 

[Taustin Powers]

I think I actually liked the Purity a little more myself for my own wants and needs, but both are pretty great, and vive la difference.

Loved my K2s BTW.

I liked the Bass Purity and played it for a few years. But the Demeter actually felt a little more lively and organic to me, hard to describe. But eventually I got tired of the K2‘s weight, sold that stuff and got an Eden WT550. Great tone at reasonable size and weight! Played that for over ten years till it broke... Then tried the Quilter BB800, which I didn’t care much for, as it lacked voicing/character. Replaced that with a Mesa D-800, which I still own and love. Considering trying out a Berg Forte HP though, because, you know, what if I like it even better?

 

[Funk With Me]

A couple times over the years I played through an SVT III pro courtesy of a backline rig. I thought they had pleasant toob preamps.

 

[hbarcat]

Maybe you should try a hybrid with dual preamps, 1 mosfet and 1 tube, so you can get a better feel for the differences that tubes make.

I have a Mesa M2000 hybrid with dual preamps and there is an enormous difference in character between the tube pre and the SS pre. There is a lot of control over the amount of tube gain and you can hear the varying amount of fuzz as the gain is adjusted up or down.

 

[teemuk]

It is quite typical to voice tube and solid-state channels according to usual expectations of how they should sound like.
Tube channel is commonly designed to be more or less "dirty" with distinct frequency response. Solid-state channel is usually designed to be very clean with less obvious color in its response. For example, in Basis M2000 tube channel has at least one or two tube stages that distort a bit whereas solid-state channel has no distortion circuitry and plenty of headroom. Tonestack is post distortion in tube channel and has different response than that in the solid-state channel. They are deliberately made to sound very different.

In some Carvin bass amps a mid-notch filter and LED clipping circuit were added to the tube channel because a mere triode gain stage did not by itself introduce enough of expected "tubeness". In some Laney amps SS signal path had flat response and tube signal path introduced mid notch of several decibels. In some Dean Markley amps "FET" channel was nothing but a wire bypass of the tube distortion circuit. And so on.

We could flip things around and design a sterilely clean tube channel (after all, that is what hifi people praise tubes for) and a solid-state channel that distorts warmly, but that would be against general expectations and I don't know how well people would receive such "tube amp".

 

[chris_b]

A couple times over the years I played through an SVT III pro courtesy of a backline rig. I thought they had pleasant toob preamps.

I used an SVT3-PRO for about 8 years, through Mesa 210/115 EV cabs. I liked the sound of that rig.

 

[Passinwind]

I liked the Bass Purity and played it for a few years. But the Demeter actually felt a little more lively and organic to me, hard to describe. But eventually I got tired of the K2‘s weight, sold that stuff and got an Eden WT550. Great tone at reasonable size and weight! Played that for over ten years till it broke... Then tried the Quilter BB800, which I didn’t care much for, as it lacked voicing/character. Replaced that with a Mesa D-800, which I still own and love. Considering trying out a Berg Forte HP though, because, you know, what if I like it even better?

Play feel is a hard thing to quantify, and it's kind of a moving playing feel for many of us. So many synergies at work. I actually tried a Demeter rack preamp through my new DIY tube power section a few days ago. It seemed to border on too much of a good thing in that room at that time but just playing a different bass through it might easily have flipped that script.