Integrated valve amplifier : to buy or to build

[navinbhat]

Hi all,

Its the classic conundrum again when it comes to valve amps: to buy or to build. I am openly seeking advice from all of you who have a lot of experience in this area and can guide me to a successful outcome.

Let me set the scene :
1. I am a newbie when it comes to valve amplifiers in the sense that I have not built one or even dabbled into it. I understand electronics and the working of valves and I can build circuits provided I have a schematic. Its the practical experience in valves that I lack.
2. For the sake of this thread, lets ignore the point about 'oh but building is fun and so organic'. I agree that doing something oneself is much better in some cases because quality can be controlled and there is no one else to blame !

Having said that, this is where I am :
1. To begin with, I was really keen to build a valve amp myself. I surfed numerous websites, postings, circuits, part retailers etc etc into the wee hours of the morning much to my wife's disdain. Most postings start of with good information and then get too technical and deviate from the core objective. Basically, I am struggling to find a simple circuit for an "integrated valve amplifier (class A or push pull) of more than 20W RMS" for which I can source all parts locally and for a reasonable price (~$450 NZD). I would be more than grateful if I could be proven wrong here.

2. Having struggled with 1, I have now resorted to ebay and am seriously thinking about purchasing one of the below :
a. MENG EL34 based stereo amp
b. Audioromy FU29 based stereo amp
I have read some postings about these but the spectra of responses are very much based around shipping and simple mistakes in the built circuit.

Now I am at a crossroad :
- shoud I give up my search for building an amp and succumb to buying ? if so, which of the two amps are worthy ?
- should I continue with my quest and if so, can someone point me to a good circuit and also a local supplier ?

Help !!

- Navin

[Gordy]

The key is time. Do you want an amp now or in eight months?

If it were me I would buy a cheapish amp to get me going and then set about designing one to beat it. So that would provide music now, plus a target to aim for in an absorbing hobby.

For a nice amp to build consider the Langford-Smith / Aston redesigned Williamson:
http://www.mif.pg.gda.pl/homepages/j...iamson-807.pdf

: )

[analog_sa]

Originally Posted by navinbhat

Now I am at a crossroad :

I have to disagree. If your wife expresses disdain towards your research, imagine her feelings once you start chasis-punching So, the decision is pretty much made, you just don't know it yet.

Even if this was a non-issue, getting involved in the diy madness just to build a single, mediocre amp is really not worth it. And it won't be nearly as cost effective as buying any well-regarded Chinese amp. Or any decent used amp.

[Robert McLean]

Navin
Just be aware that there is no such thing as building one amp.
You learn from the mistakes made during the first few you build, and you acquire the tools, test equipment and components needed over a period of years.

So, you either take it up as a long term hobby, or just buy one.

[DreadPirate]

You have not mentioned a third option, which is to restore an older amp. The Scott integrateds are nice and can be had in your price range. You would be dabbling in the tube waters prior to diving in. I don't think you can find a new 30W integrated at your price, but who knows.

more: Yikes! Apparently you can!

http://cgi.ebay.com/MENG-X3-EL34-x2p...item3ca8c5d147

[rotaspec]

Originally Posted by navinbhat

Hi all,
Now I am at a crossroad :
- shoud I give up my search for building an amp and succumb to buying ? if so, which of the two amps are worthy ?
- should I continue with my quest and if so, can someone point me to a good circuit and also a local supplier ?

Help !!

- Navin

I take it by the flag that you are in NZ, in which case I doubt you will find a local supplier of the big parts. That means shipping big items from overseas or getting them custom made, and trust me, shipping will DOUBLE the purchase price of a transformer for example. You may as well ship an entire amp out of Hong Kong, it will be as cheap including its purchase price, as two medium quality transformers from the US.

However, I would do some research into the various brands and their power claims before venturing into the Asian amp market.

You could look for a local amp to restore, but most are way below your power requirements, and are almost always to be found in a radiogram chassis. Typical old school NZ amps are in the 2W to 5W category. Remember, stereo (like colour television) didn't arrive en masse in NZ until the late sixties, which was well into the solid state age.

Oh, and if you don't want to risk unknown vendors on eBay, try on9mart in HK. They seem to have a good reputation and their online prices include air freight worldwide. I haven't dealt with them personally, but know people who have. My Meng Mini came from them.

Gary

[Ty_Bower]

Originally Posted by rotaspec

That means shipping big items from overseas or getting them custom made, and trust me, shipping will DOUBLE the purchase price of a transformer for example.

NZ makes me think he should look at Patrick Turner's offerings in the transformer department...

Turner Audio

[aardvarkash10]

Originally Posted by Ty_Bower

NZ makes me think he should look at Patrick Turner's offerings in the transformer department...

Turner Audio

hehehehehehehehe - still pricy. Patrick's stuff is great, but heavy and still outside the op's price range. And he is still over 2,000 miles from the op.

Being a godzoner myself, I sympathise with the op. The stuff that looks so reasonable to the northern hemi types takes on a whole new look from down here.

As an entry point, I'd go with the built up ex-China amp. You can always mess with it later, or start assembling bits for the ultimate build that will replace it. Especially at the power output you are looking for.

[Brit01]

Once you start messing and modifying then you will get hooked!
Every little improvement to hear is like a drug
and you continue and continue...

But its fun

[sauuuuuce]

I say buy one off eBay for cheap....20W is PLENTY. You could go less. If you like it, you have three options;

1) Buy another, "better" Tube Amp
2) Build another, "better" Tube Amp
3) Buy another cheaper tube amp and mod it.

If you're not TOO familiar with valves it may be easier to mod one than to go from scratch. Of course there are always Bottlehead Kits and the like.