A new amp for your studio

About a year ago I asked a question of forum members. "What would you like to see in an amp for your studio".
 
I didn't get a single response so I just moved on. Well, I've been thinking about it and have designed and built a new amp for both a home and professional studio. The amp is a fairly simple single output tube design, 100% hand wired with the best parts I could find. It will use almost any 8 pin pentode or beam power tube. Anything from a 6V6 to a KT88. THe pre-amp features a 3 band EQ and an EF86 front end. 
 
What makes this amp different is that it doesn't sound like a small amp. It is REALLY quiet and uses transformers with a broader frequency response than most guitar amps. This allows you to run guitar, bass or keyboard through the amp with excellent fidelity.
I won't go on much more for now since the entire project is being published online as a 3 part article. The first part is up now and the next will follow in a few weeks. I don't give exact instructions on how to build the amp for reasons of personal liability, but I will be providing enough information for you to do so if you have some experience.
 
Here's a link to part 1.  http://blog.thetubestore.com/if-you-cant-find-it-build-it-diy-amp-part-one/

i think if i was starting up a 'studio for hire', i'd go with a Kemper Profiling amp.
 
of course,
having a stable of basics (Fender Vibrolux, Marshall JMP, Vox AC30) would cover 95% of everything.
 
but having a custom built amp,
is what i called 'dialed in'

Thanks for sharing that John! I was just thinking about how much I'd like to try out a 65Amps Ventura which also has an EF86 and 6V6's, if memory serves.
Michael

There is a difference between tubes that's hard not to notice and the design is such, that you can reliably switch between them. Most of your questions will be answered in the articles, so I suggest you read them if you're interested.

That's a really cool looking design. I might just have to give this a try... I will be waiting (patiently of course) for your approach to a switch-able output tube design. I've tried in the past, but never been happy with the compromises I had to make.
 
Very nice of you to share the fruits of your labors!!! I hope to return the favor.

soens
To answer a year late, I'd say: An amp that makes -0- noise (no fans - no hums) and delivers clean sound at all frequencies at an affordable price. ...
 
But I want too much.

One of my design goals was to make the amp dead quiet for studio use. It really is dead quiet. I also used an output transformer that's rated from 40 Hz to 18 KHz. I've tested it with a 4 string bass and I'll be visiting a great Canadian bass designer very soon to see how it works with active and passive 5 string models. When using bass I run a 6550 or KT88 output tube. When I use guitars it's usually anything from a 6V6 to 6550. I have a dual range bias control to enhance each type.
 
Affordable is tough to answer, but I will do a proper accounting of the build.

This is awesome, John and thank you for sharing. As I said to you before I am no electronics talking guy but am very interested in learning... specifically about things like this. One of the things I'd like to do if I get the chance is to take some basic electrical engineering courses so I can actually understand things like this and toss together simple preamps to use in my modest home studio. I've known guys that do this type of work and some of the boutique shops I used to poke around in carried custom tube pres (one of the coolest I saw was tube preamps built into old army surplus ammo boxes). I also like screwing around with old, obscure gear that people don't give a crap about because it's broken and/or they are recognizable names. I've gotten very cool and useable stuff that way and just tossing a few bucks at repairs. If I knew a bit about repairing and modding such things I could rebuild my dark army of backline gear just by scrounging around Craigslist or whatever.
 
Anyhoo... it's awesome you are willing to share your insights and experience with us.
 
Cheers.

I think I have heard of these Filmo's through some of those gearheads I was telling you about. I was always an "Is it loud? Does it work?" kind of guy because I just wanted plug in and play but now that things are going to tape I wish I had paid more attention. Need to see if there are any electronic supply shops around here but I doubt it. I guess all that stuff is available online now though. Ain't the same as picking the brains of the guys behind the counter.
 
I'm guessing you've meandered through Active Surplus when it was still going. That was a wacky place.
 
 

Guitarhacker
Great read....
 
 
Are you planning to post the schematic with values?
 

 
You know what? The schematic is in my head, I never did write it down. It might be a good idea to draw it all out.

The choice of 2 bias ranges allows for operation at 10 watts or 15 watts. If I only had 1 bias setting then a 6V6 could be run over its maximum output rating or bigger tubes could run cold. 2 ranges allows for a good balance and keeps everything running cool. I've thought about stereo type amps before but I have no plans to build one.
 
In upcoming articles I will be doing the building in detail, with lots of pictures and explanations of my choices. It will be about 2 weeks before the next part gets posted.