Tube preamp scheme.

[sanyaalwaysbass]

Hello everyone! I'm in search of a good tube preamp scheme. It's assembling must not be expensive like alembic f2b or ampeg svt pro.
I will be grateful for any
help you can provide.

[majortoby]

Well, first thing's first. How conversant in electronics are you? This sort of undertaking can be seriously dangerous and fruitless to the uninitiated. Just a thought.

[sanyaalwaysbass]

sorry, i'm forget:

>Please note, that
it has to be easy to assemble,
because my friend-engineer will
be in charge of that.

[BassmanPaul]

Take a look at the front end of an Ampeg B15. It's about as simple and straightforward as a pre-amp can be. If you are wanting to use this to drive a SS stereo power amp, you'll need to add a cathode follower to the output, preferably with some kind of output transformer. That should be a simple task for an engineer with a knowledge of tube electronics.

[bgavin]

Has anybody seen an "open source" schematic for the ultimate DIY design?

[Codger]

Originally Posted by sanyaalwaysbass

Hello everyone! I'm in search of a good tube preamp scheme. It's assembling must not be expensive like alembic f2b or ampeg svt pro.
I will be grateful for any
help you can provide.

I replied to your duplicate posting over in Pickups & Electronics.

[MAMMOTHvolume]

check out the g9 preamp

[bgavin]

Originally Posted by MAMMOTHvolume

check out the g9 preamp

Link?

[synaesthesia]

http://www.gyraf.dk/gy_pd/g9/g9pd.htm

[ThisBass]

Hiwatt

[nashvillebill]

The Alembic is basically a Fender preamp and tone stack, can't hardy get much simpler for a preamp.

[majortoby]

I'm detecting english as a second language here. Where are you located? That could help us help you

[fdeck]

Originally Posted by bgavin

Has anybody seen an "open source" schematic for the ultimate DIY design?

Are you volunteering?

A nice idea might be to show a preamp build, progressively, starting with the most basic features. A couple of gain stages with a passive tone stack in the middle is about as basic as it gets. Then you can add things like midrange, DI, etc.

[majortoby]

Originally Posted by fdeck

Are you volunteering?

A nice idea might be to show a preamp build, progressively, starting with the most basic features. A couple of gain stages with a passive tone stack in the middle is about as basic as it gets. Then you can add things like midrange, DI, etc.

+1
I agree that starting with a very basic pre would be the way to go. At least starting out, you could probably get nice results with a couple gain stages, a SIMPLE eq, and cathode follower.

It would not be the most versatile device ever crafted, but you would have the ability to tweak it more to your liking, and develop a better picture of where you want to take it from there.

And you never know, a simple clean pre with minimal eq just might be your dream tone

[BAce]

A single channel Alembic F2B is about as easy a tube preamp build as you will find. And they sound great. I did one a while back and I love it. It was however my 27th amplifier or preamplifier build. Mine isn't exactly stock either--D.I. out as well as the normal output, cathode follower, a few extra switches. So do some reading, look at a LOT of pictures of finished builds to get an idea of how these things are put together.

[bgavin]

Originally Posted by fdeck

Are you volunteering?

I wish, but I'm not at all literate in circuit design. Speakers are my thing.

I've seen a few point-to-point photos here on TB of units that are superbly constructed for ease of service.
These don't have the compromises required for mass production, i.e. surface-mount, printed circuit boards, pots soldered to boards, etc, etc.

This is not the correct forum, but I suspect somewhere there is in-depth discussion about circuit design for the ultimate bass preamp.
My SVP-Pro schematic thread got a bit of discussion going, but it did not continue.
Some of the smart design guys were chiming in as to why a particular circuit was good or bad, and what was required to improve it.

I wouldn't object to paying top dollar for a well-designed custom preamp, with full schematic, that is fully serviceable (point to point) long after the maker exits the business.

My daughter's 1985 JCM-800 is an amp like this.

[Passinwind]

Originally Posted by bgavin

I wouldn't object to paying top dollar for a well-designed custom preamp, with full schematic, that is fully serviceable (point to point) long after the maker exits the business.

My daughter's 1985 JCM-800 is an amp like this.

What's your idea of top dollar Bruce? And how custom would it need to be?

Personally, I don't consider turret or terminal board construction to be functionally any better or worse than good printed circuit boards -- especially if they're wired by a beginner's hands. The '85 JCM800s used a printed circuit board, BTW. '85 is right around when Marshall started doing board-mounted pots and jacks too, so your daughter's amp is quite desirable if it's the old style build.

[Clark Dark]

Originally Posted by sanyaalwaysbass

Hello everyone! I'm in search of a good tube preamp scheme. It's assembling must not be expensive like alembic f2b or ampeg svt pro.
I will be grateful for any
help you can provide.

If you're not into the Alembic F2B then try the Fender Dual Showman

[Codger]

I mistook the OP's comment to read that he considered the Alembic F2B or Ampeg SVT Pro to be an example of the "must not be expensive" type. I think you'd struggle to find a tube preamp simpler or less expensive than an F2B. Maybe with no tone controls?

[dhsierra1]

TBer Passinwind is one of the pre-amp guru's around here, he posts on different builds pretty frequently. Do a search on some of his stuff, then PM him.