[rockdrummer]

I'm working on a pair of GR Research monitors and love the DIY process. 

I am looking for suggestions of full kit tube amps.  For my first go-round, I need it to be cheap.  Upwards of $300 could be possible.  I know that is limiting, but I'm thinking it's more of a practice.  Of course I'm hoping for decent quality watts, but I'm tempted to pull the trigger just for the fun of the build. 
I know of Bottlehead, but that's in the running for my eventual goal of a good amp.

In the last several months of hanging out on AC, I have seen many names of brands, and I have found a couple Chinese companies that sell parts, or kits but I am wondering about gear people have experience with.

Thanks for any and all info.

I also need to read up on the differences between 2a3, PP, 300b, etc.  I'm new to tube amps in home stereo.


Ben

[Ericus Rex]

Have you checked out tubelab?

http://www.tubelab.com/PCB_order.htm



He states the SSE amp could be made for as little as $300.  Check out Pez's build of this amp:

http://www.audiocircle.com/index.php?topic=73713.0

[corndog71]

$300 is pretty limiting.  I would suggest saving up a couple hundred more and putting together a Dynakitparts ST35 or see if you can find a ST70 on ebay.

[sts9fan]

If you aren't hung up op bottles you can make two very nice gainclones for $300.

[jtwrace]

If you aren't hung up op bottles you can make two very nice gainclones for $300.

Link?

[jeffh]

Link?

Here are two popular kit vendors:

http://chipamp.com/

http://www.audiosector.com/

Also check out the Chip Amp section at diyAudio.com

[Æ]

http://www.s5electronics.com/thome.html

[wushuliu]

Have you checked out tubelab?

http://www.tubelab.com/PCB_order.htm



He states the SSE amp could be made for as little as $300.  Check out Pez's build of this amp:

http://www.audiocircle.com/index.php?topic=73713.0

+1. The nice thing about the tubelab simple se/push pull: thorough documentation, parts flexibilitity, cost. So you can try different types of tubes, upgrade parts over time, and the sound quality will only get better with improved modifications. Not all tube amp kits have this kind of flexibility/adaptability and this way you don't waste a couple hundred on a poor sounding/dead end first project. And the tubelab forum on diyaudio is a GREAT resource when (not if) you need some help. The Tubelabs are gifts that keep on giving.

The toughest part is building a chassis. $300 means you will have to build your own. Double that amount and you then can do the all in ones mentioned above like the Dynaco or Oddwatt, etc.

Do not buy any chinese kits/amps!!!!!!

The gainclones also sound like a good inexpensive first amp project.

[sts9fan]

Link?

www.google.com

[bigjppop]

I've got the tubelab simple SE and it's a great amp, but I blew past 300 really fast, especially if this is your first build and you have to buy all the tools and the odds and ends like I did. That really has nothing to do with tubelab, it's going to be the same no matter what you build. If you've got all the tools/stuff you need to build, you could do it for 300 if you get creative.

[JLM]

Make sure you match the power output to your room, taste, and most importantly speaker efficiency.  Most recommend being able to reach at least 105 dB peaks, some much (impractically IMO) higher.  Example: to reach 105 dB with 2 speakers in a 12ftx20ft room with 89 dB/w/m speakers requires 40 wpc (and confirm impedance - ohms - ratings for both speakers and amp to make sure they match too).

Pushing a too small amp too hard, even with tubes, will result in loss of dynamics and possible clipping which can easily fry tweeters.

[rockdrummer]

Thanks for the numbers rundown, JLM.  I guess what I need to decide is whether I upgrade speakers before building an amp.  I'm probably ahead of myself.  Whatever speakers I do get will hopefully be higher sensitivity, maybe rated @ 95-97db.

Spent lots of time on tubelab's site yesterday and today.  Certainly makes me wonder if I shouldn't just plan on spending more and making it more a long term piece of gear. 

ben

[JLM]

ben,

Rock concerts reach 110 dB, but your tastes could be more "mellow".  OTOH I wouldn't want to limit myself like that.  A recent thread in the Salk circle here at AC mentions his 88 dB/w/m speakers needing all of 300 wpc (roughly 112 dB).

High efficiency speakers provide lifelike dynamics, but sacrifice tonal accuracy (what many called a "colored" sound), and they will reveal all the warts (self noise) in your source/electronics.  IMO 93 dB/w/m at 8 ohms is the ideal compromise.

There is a huge thread here in Cheap and Cheerful for good sized DIY digital amps.

[Ericus Rex]

Do not buy any chinese kits/amps!!!!!!

What's you experience with Chinese kits?

[JDUBS]

www.google.com

   Nicely done.

-Jim

[Ericus Rex]

http://www.s5electronics.com/thome.html

How does it sound?

[Æ]

How does it sound?

Well, it sounds pretty much like many a tube amp, warm and euphonic. I did notice that this particular amp sounds somewhat different depending upon the load, that it doesn't like low impedance loads. Highly reactive loads (loudspeakers with complex impedance) affected the frequency response, tonal balance. I like the way this amp handled midrange, but not so much tweeters, treble.
I no longer have the amp, I sold it to a gladsome buyer.

[rockdrummer]

Oh, sorry AE, I didn't notice you built that amp.  I'm going to go back to that site and do more research.  I've watched and read up on soldering boards, etc. but where I will do more research is how to choose the rest of the parts.  Thanks,
Ben

[Æ]

Oh, sorry AE, I didn't notice you built that amp.  I'm going to go back to that site and do more research.  I've watched and read up on soldering boards, etc. but where I will do more research is how to choose the rest of the parts.  Thanks,
Ben

Well, the kit amp I bought comes with all necessary components, you only have to assemble (solder) it and provide it with some sort of case or chassis. Of course I upgraded to better components where and when I felt it was appropriate. Kind of like you get what you pay for.
Basically all you have to know, is to buy the best and skip the rest. Ha. Well buy what you can afford.
Typically I strive for component accuracy. I always try to source one percent capacitors and resistors. Grade and match all your components whenever possible. It requires that you have the ability to measure them. I have an LCR meter and a DMM.