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Need advice on Val Audio amp with EL-34 Tubes

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Hello to all! I had purchased a vacuum tube stereo amplifier a few years back and was wanting to upgrade it to a more high fidelity amp. The amp is a Val Audio VP-110S. I was thinking on replacing the tubes with maybe some Mullards or perhaps some Black Sable's,ect. Also wanting to know if it would be worth-while to change some of the caps inside with better ones? Any help or advice would be appreciated!

Thanks,
FSHZ:43 :)
 
I googled this and couldn't find anything on it so I have no idea how good of an amp it is to begin with. First off, if it's an economy amp, buying a set of mullards is ridiculous - they cost almost as much as the amp - and there are plenty of mods you could make to get better sound for much less money. The Siemans/RFT German EL34s can be had for 100-200 USD and are IMO the best deal on NOS EL34s - the mullards aren't that much better to warrant $500 a set. (my opinion) Again, not knowing what you have in it now, how can we say what's the next step up? Changing the coupling caps to high grade is probably the easiest and fairly cheap update you could do on the inside. Again though, since I have no idea whats in it... how do we say this is the next level...? maybe you could post some info on this amp, tubes and parts in it... schematic if you have it... etc...
 
Cycline3, Thanks for trying to help! I had purchased the amp around 4 or 5 years ago for around $450. It is a V.A.L. vacuum tube amp with 55watts per channel. The information that came with the amp is limited. There are 2- EL34A tubes per channel with 2- 6N3 tubes on the signal-path. I had checked around for other tubes to upgrade for a better high-end sound, but with little luck. After speaking with several people, one says that the 6N3 tubes are a hard tube to get, and by changing them out would give much better sound because they are in the signal path. Another guy at a tube shop on the web said by replacing the stock tubes with Black Sable's would be very good for sound improvement. I was also told that this amp was manufactured in China. Just my Luck!

Someone else said that I could do some changes inside to modify some things, so that I could upgrade to better tubes and that if I needed to ever replace them, that they would be much more available. What do you think would be the correct way to go?

Thanks,
FSHZ:43
 
I found a pic of your amp on a Chinese audio site, uses 4 x 5670 tubes instead of 6N3's. Those 6N3's are probably a Chinese copy of Russian 6N3P's, which are a military tube, and certainly of much higher quality than the Chinese equivalent. 6N3P is listed as a direct replacement for 2C51/5670/6CC42 tubes. This might be a good place to start as someone suggested.

I agree with Cycline3's comments regarding spending big bucks on NOS EL34's. There are decent new tubes available for <$100/quad.

Jeff
 

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OK... keeping it simple - upgrading the preamp tubes to Russian versions will likely give you a plug and play improvement. As for the EL34 - I just posted a thread for the best CURRENT PRODUCTION EL34 and SED seems to be the winner - at about $80 a quad. These are said to be similar to the old Svetlanas - of which I have some and they are indeed very good - closely approaching NOS tubes. Again, I say, NOS Siemans is the best deal for the absolute best sound. Better tubes does equal better sound. So, Upgrading tubes can make a big difference. But are $500 tubes right for a $450 amp? I don't think so... start small.. work up. Get some SEDs or Siemans and see if they make a difference to you...

Now, not so simple. Do you want to modify the guts of your amp? DO you know how? Do you want to learn how? Or would you rather hire someone to do it? Im not sure what you are wanting to accomplish. Modifying the preamp to use standard tubes would help you get better sound by giving you a wider selection of tubes to choose from. BUT - that's not a trival matter. It would take some work and know how, and unless you know what you are doing, you might make the amp sound worse. It wouldnt be the first time that has happened. Again, give us some more feedback. From the pic, it looks decent - and like it certainly is worth keeping and upgrading.
 
Thanks again guys for the help! As far as upgrading this amp, I do have a little electronics background as to reading schematics, building passive X-overs,ect. I would like to upgrade this amp to a higher end audio amp. However, I am not that familiar with tube amps as to go inside, and start changing out components, unless someone was willing to help me out as to doing this. It wouldn't be a problem if I had the schematics for this amp, as to go in and change out some caps or whatever else needed to be changed to up-grade it. Back to the tubes: Are these SED tubes the best bang for the buck? And should they sound more musically detailed then the stock tubes? Also, what other brands of tubes are out there that would replace the stock 6N3's that would be a good match for the SED's? Any feed back on the Black Sable tubes?

vinylkid58: Thanks for the info and picture!
 
Not sure how many posts but it does seem to take a little while... if you want to upgrade the inside, I think you will find lots of people here willing to help. You need to read the safety and tube newbie threads before you start. Working on a tube amp can kill you if you are not safety minded 100%. They operate on very high voltages.

Then instead of looking for a schematic, why not trace and draw one yourself? You need to be able to trace and follow the parts in the amp if you are going to modify it, and that would be a good way to get you familiar with the amp you have.

If you are going to move to a standard tube for the drivers, you have a wide open canvas to select the circuit type you want to build. That said, you should also be prepared to be without your amp for an extended period, as you will have it on your bench awhile during the process of educating yourself, finding parts and asking questions here... building, testing, listening... going back and revising, repeat....

Like you said, a tube roll / swap may be the best place to start...
 
I had the VAL MP120S which used the 4x 6550 ,2x 6SN7 ,1x 6SL7
It responded really well to modifying .
Removed the passive pre section ,replaced all tubes with NOS ,replaced all resistors with Mills & Riken Ohm ,replaced power supply transformer and all caps with BlackGate's .Coupling caps Auri ,MultiCap Styrene and LaClanche and the hookup wire .
The only thing left was the output transformers which where wound for better bass ,I had it for 12 years .
Cheers .
 
FSHZ:42 said:
Almost forgot! The only cross-reference that I had obtained from the place that I purchased the amp was for the 6N3 tubes which are: 6U3 & EY82

6U3 & EY82 are rectifier tubes, not even in the same category. In North America, look for 5670/JAN 5670WA etc. These look to be a smaller tube physically, probably shorter than the 6N3's currently in your amp.

Use Frank's tube web site to search for tubes or equivalents:
http://www.tubedata.org/

Jeff
 
vinylkid58:

So basically what you are saying is that the cross reference of the 6N3 tube is either the 5670/JAN, or 5670WA? And also the cross-reference that was passed on to me for the 6N3's being replaced by either the 6U3 or the EY82 tubes are incorrect?
 
FSHZ:42 said:
vinylkid58:

So basically what you are saying is that the cross reference of the 6N3 tube is either the 5670/JAN, or 5670WA? And also the cross-reference that was passed on to me for the 6N3's being replaced by either the 6U3 or the EY82 tubes are incorrect?

Yes, read my post #4 again for cross ref.

Yes, 6U3 & EY82 are NOT a cross-ref. for 6N3.

Are the stock EL34's in your amp Shuguangs?

Jeff
 
Not sure if they are Shuguangs, so here are the only numbers I can see on the tubes: 6CA7 and under that is EL34. This is all I have to go by. Also, where can I purchase the 5670/JAN, or 5670WA tubes, and will they be more musical in detail then the 6N3's?

Thanks,
FSHZ:43
 
A quick google lists several pages and forums that say the 5670 is a drop in replacement - though I didn't find the specs on the 6N3 to compare and be sure. But I'd assume since there are people saying, I dropped them in and they sound better... that, they'd sound better. Now... I only wonder what you'll have to pay for some NOS GE5670s...
 
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