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Looking at building a tube amp and preamp

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I do suppose its worth asking how much power do you actually need, and what sort of budget are you working with. Options exist from 1 watt to 120 watts per channel. Need something to narrow that down a wee bit.
 
BassKulcha said:
I would build these:

valvesnmore.com

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Looks like it must be a triode connected GU50 which is a bit of a waste. It doesn't make a very good triode for SE but is marvelous as a pentode with some plate-to-plate feedback and will give about twice the 8W power at low distortion. The GU50 in triode should also be good in PP. I've built a prototype SE in pentode with pentode driver and the local feedback. The measurements and sound quality are very good. Problem is you are looking at a complete DIY build rather than a kit.

All the best,
John
 
gadget73 said:
Personal opinion, I would not build an ST-120. If I wanted that much power I'd build a pair of Mark III mono amps instead. No shared power supply, and much less weight to deal with at a time.
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I agree. Or the ST-70. I looked closely at the Tubes4Hifi ST-70 and ST-120.
I did a lot of searches for both. Reviews, problems, etc. And decided on the ST-70. The MKlll mono blocks would be the better choice between them and the ST-120. The difference in volume output between the ST-70 and
ST-120 is only going to be around 3db, but you would get a little more head room from the ST-120 or Mklll's. Dynakit sells MKlll kits but they seem to be out of output transformers most of the time.
I really like the ST-70 though. With the 12AU7 board you have more choices in driver tubes you can use with either the ST-70 or ST-120. 12AU7's, 12BH7's, E80CC's, and ECC99's. You also have more choice for power tubes in the ST-70. Various EL-34's, KT-77's, and 6CA7's. I tried some KT-88's, but they just didn't sound right in the ST-70.
There are a lot of different preamp kits out there. I really like the Aikido line stage preamps. If you want tone controls there are various kits also.
 
nerdorama said:
Looks like it must be a triode connected GU50 which is a bit of a waste. It doesn't make a very good triode for SE but is marvelous as a pentode with some plate-to-plate feedback and will give about twice the 8W power at low distortion. The GU50 in triode should also be good in PP. I've built a prototype SE in pentode with pentode driver and the local feedback. The measurements and sound quality are very good. Problem is you are looking at a complete DIY build rather than a kit.

All the best,
John
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I can't speak to the GU50, but OP mentioned also wanting to look into building a preamp, and I think their Universal 6or12sn7 looks great. I guess I'm not understanding your difference between a kit and DIY—these kits seems to be of a similar build level to the original Dynakits, Healthkits, etc. (unless you're referring to your prototype SE pentode build being the DIY example?)
 
That jives with my definition. Kit is a pre-cut chassis, a set of parts, and instructions to put it together. Think Heath, Dyna, Eico, Knight, etc.

Full on DIY you have a schematic, or in extreme cases a piece of paper on which you create your own schematic. On your own for chassis fab, component selection, layout, assembly order, etc.
 
Build a few kits, they'll teach you what you're capable of, give you ideas and practice soldering. If you get bored assembling kits, just know that you can go much deeper into this rabbit hole and build 100% from scratch.

I got bored with kits and built myself a tube preamp from scratch. There's a thread on it, I call it the "members only" preamp. The game changer for me was realizing that I could take elements from things I love like a HH Scott phonostage and a push pull line stage from a DIY article, my own input switching arrangement and a power supply schematic, modified to work, put it all in the same box and get exactly what I want without making any compromises.

The same can be done for power amplifiers, crossovers, and on and on.
Decide what you like to use and keep using it, keep tweaking and refining it. It's a lot of fun.
 
ceylon said:
aikido is out of stock on all line stage preamp and phono amp.
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Whats up with Glass-Ware? They seem to be out of stock every time I look at the site.
There are a few other options with complete kits of the Aikido.
 
You can find the schematics for Akido design line stages, and phono stages over at DIY audio
Once you have the schematic you can order the parts yourself. You'll miss out on a lot of learning if you let someone else source all of the components.
 
both kit and scratch build are DIY, just scratch build and rebuild is doin a bit more.
 
I do like the octal version of the Aikido compared to the Novel version I built. There wasn't a huge difference, but there was a difference for the better with the octal's.
 
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