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First time builder, need advice.

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I am a first time builder and I would like to build a tube amp. I am looking for the right schematic for my budget and results.

Is the 300b all that much better for the expense or can I save some money and get similar results ?

Is there a popular all around great schematic out there (Parts availablity and costs ) ?

Where is the best source for transformers ( quality and price) ?

Any tips or things to stay away from doing from personal mistakes would be great :)

Thanks all !
 

G

Member
Joined 2002
apetersn said:
I am a first time builder and I would like to build a tube amp. I am looking for the right schematic for my budget and results.

Is the 300b all that much better for the expense or can I save some money and get similar results ?

Is there a popular all around great schematic out there (Parts availablity and costs ) ?

Where is the best source for transformers ( quality and price) ?

Any tips or things to stay away from doing from personal mistakes would be great :)

Thanks all !

First what is your budget? Second, what is the sensitivity of your speakers? Post back and we'll go from there.
 
Re: Re: First time builder, need advice.

G said:


First what is your budget? Second, what is the sensitivity of your speakers? Post back and we'll go from there.

I would like to do this for around 400.00, I thought I could build from the ground up and then if I need to I could thow some more money at it. I am finding that the big expense is transformers. It blows me away how much some wound wire costs!

I am thinking I am probably going to build some speakers in the future, but at this time I will be hooking this up to some JBL L40s.

I have been looking at some of the J.E. Labs schematics and I like the simplicity of the 300b and the PP2A3 for a first time project. It seams from there I could build on to either one.
 

G

Member
Joined 2002
You will definately need to go Push Pull with those JBL's. You might think about picking up a Dynaco Stereo 70 on Ebay and rebuilding it. There are lots of new boards and parts for them available and you could pick one up for around $250 on Ebay.
 
G said:
You will definately need to go Push Pull with those JBL's. You might think about picking up a Dynaco Stereo 70 on Ebay and rebuilding it. There are lots of new boards and parts for them available and you could pick one up for around $250 on Ebay.


I am actually wanting to start from scratch. Have you ever looked at the JE Labs schematics? Do you think I will be into this a ton of money?
 
I started out with a Bottlehead.com tube preamp kit, and my first scratch-build was an SE 2A3 from JE labs (or Angela.com, since that's where I saw the schematic and bought the parts from). My speakers were/are 95-96dB sensitive though, and I don't have a very large room, so that worked out fine for me. I think it cost me roughly $500 for my first build, with the cheap Hammond 125ESE (hope I got the name right) transformers. Since then I've upgraded to One Electron transformers and changed my driver stage, so I think I have 700 - 800 in the amp now. For my first build I did go with the resistors/caps recommended on their website. If you pick up cheap R/C from say a surplus store (which is what I eventually ended up doing for some parts of the amp), you could save some money. Re-design the power supply to use SS rectification and maybe no choke in the PS, and you'll save another chunk of money, but you'll probably have a noisier PS.
 

BHD

diyAudio Member
Joined 2004
Hmmmm.... :scratch2:

With that budget you'd probably be better off sticking with a push pull amp with solid state rectification.

You may be able to build the stereo version of the JE labs on that budget, but it'll be tough. The 400 dollar budget can't include the cost of tubes, since 300B's usually start at 100 bucks each. I'd say buy the output trannies and choke new, either Hammond or One Electron. Then you have to be patient and scrounge for the power tranny. I bought a new power transformer (a really hefty one) for quite a few bucks, and not a week later this really cool UTC power transformer came available on Ebay for a third the price. :irked: I bought it, and now I have an extra one for my next project, but I should have been patient. :grumpy:

You'll need to fabricate your own chassis and you won't be able to use super spendy "boutique" parts. Good luck!
 
Hi,

Here is the thread I'd started when I was building my amp. It has lots of dumb beginner questions, and good answers from the experienced people on this board. And like I said, it's a JE Labs 2A3 design.

There are a couple of other threads on here that go through a step-by-step description of the construction, the decisions taken, and the reasons behind those decisions. I found those very helpful when building my amp, and I think you would get a lot of information that would save you time and money if you searched for those threads and spent some time looking through them.
 

G

Member
Joined 2002
Re: Re: First time builder, need advice.

apetersn said:



I am actually wanting to start from scratch. Have you ever looked at the JE Labs schematics? Do you think I will be into this a ton of money?

The least I've ever spent on a project is about $400. That is with cheap output transformers and a old power transformer that I bought on Ebay. Are you wanting to do single ended or push pull? What type of music do you listen to?
 
Saurav said:
Hi,

Here is the thread I'd started when I was building my amp. It has lots of dumb beginner questions, and good answers from the experienced people on this board. And like I said, it's a JE Labs 2A3 design.

There are a couple of other threads on here that go through a step-by-step description of the construction, the decisions taken, and the reasons behind those decisions. I found those very helpful when building my amp, and I think you would get a lot of information that would save you time and money if you searched for those threads and spent some time looking through them.

Oh sure! Go ahead and get Frank & Sy involved! Frank will want to regulate the AC mains coming out of the wall!! ;) ;) ;) ;) ;) Just kidding Frank. Seriously though. You can spend as much or as little as you want to. What is your goal? $400 is not a lot of money for a tube amp project. You will spend about $200 just for good output transformers. Bottlehead Paramours are a good kit at a good price but you will need different speakers. Full range Fostex speakers are certified ear candy with SE amps:

http://www.quarter-wave.com/Project05/Project05.html

The Paramours can be found here:

http://www.bottlehead.com/et/adobespc/Paramour/paramour.htm

You won't believe the sound from this combination. Cheers.
 
diyAudio Senior Member
Joined 2002
Hi,

But I think you can safely ignore them both

No you can't....;)

Anyway, this my adaptation of an idea by dutch audio fellow Triode Dick":

It's PP, uses solid state rectification and my favourite DHT triodes:

Cheers,;)
 

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Re: Re: Re: First time builder, need advice.

G said:


The least I've ever spent on a project is about $400. That is with cheap output transformers and a old power transformer that I bought on Ebay. Are you wanting to do single ended or push pull? What type of music do you listen to?

I really listen to a huge variety. Would a person be better off going with a push pull just to be safe? Is there a simple way of explaining the difference in an audio aspect. It seams to me that the PP design would offer much more power?
 
Frazzled said:
Yes I think I have settled on the 300B I posted in my thread, I have already started buying some of the required parts.

I will keep you up to date...;)


Excellent, What made you lean towards the 300B, I must admit that the looks of it in itself and its simplicity is a big seller for me. I can adjust and or build some speakers if the results are not what I am looking for. Have you purchased any transformers and are you going with the circuit that you posted ? If you have purchased transformers where did you purchase them from and which did you decide on ?
 
G said:


Oh sure! Go ahead and get Frank & Sy involved! Frank will want to regulate the AC mains coming out of the wall!! ;) ;) ;) ;) ;) Just kidding Frank. Seriously though. You can spend as much or as little as you want to. What is your goal? $400 is not a lot of money for a tube amp project. You will spend about $200 just for good output transformers. Bottlehead Paramours are a good kit at a good price but you will need different speakers. Full range Fostex speakers are certified ear candy with SE amps:

http://www.quarter-wave.com/Project05/Project05.html

The Paramours can be found here:

http://www.bottlehead.com/et/adobespc/Paramour/paramour.htm

You won't believe the sound from this combination. Cheers.


Great! This is going to get expensive quick! I looked at the Fostex speakers and some options for cabinet designs and they are fairly reasonable in price. I am getting excited about building some of those in the near future.
 
apetersn said:



Excellent, What made you lean towards the 300B, I must admit that the looks of it in itself and its simplicity is a big seller for me. I can adjust and or build some speakers if the results are not what I am looking for. Have you purchased any transformers and are you going with the circuit that you posted ? If you have purchased transformers where did you purchase them from and which did you decide on ?


I guess it would be the simplicity of the SE circuit and the fact that I like the look of the 300B tube and after I finish building the amp I can always upgrade it simply by purchasing the WE300B tubes.

I have started picking up the parts I need but I am keeping my eye open for some vintage trafo's, and I am making a few changes to the circuit as suggested by Eli Duttman (thanks Eli).

For me the power issue is irrelevant as I have some pretty big SS amplifiers laying around, if I want loud I can get loud, what I am looking for here is to kick back in my easy chair with a scotch and listen to some Vivaldi and stare at the gentle glow of those beautiful tubes:D

That in a nutshell is what I wanted as an end product.

P.S. the amplifier is the small part of the total investment, now I am looking at a turntable so I can start collecting some vinyl :drool:
 
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