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James G
06-05-2009, 13:36
Hey guys, I'm hoping to get some advice these caps in my amp (TRV-35SE). I'm not sure about the application so I have included a photo. They are the copper colored Vitamin Q caps. Just an uneducated guess is that they are cathode bypass caps? Sorry but I have't been able to find any schematics for you to look at.

I noticed that on the images (last page) in the amp's owner manual they are different caps (white plastic).
http://www.triode.co.jp/en/contents/manuals/TRV-35SE.pdf

From what I could find on the net the VitaminQ caps are mostly described as warm, smooth, nostalgic, etc. What I'm looking for in sound is more like open, detailed, clear, etc. Something that will let ALL of the sound of my tube choice show through. Then I will see about getting some quality NOS tubes, maybe something like the ones Marco got in his Ultimate ECC83 thread.

Would changing these caps to a different type such as a Mundorf Supreme or the like help get me closer to what I'm looking for, or am I barking up the wrong tree? Any suggestions much appreciated.

http://i577.photobucket.com/albums/ss213/jgjpn/Stereo-002.jpg

jonners
06-05-2009, 15:47
James -

I would think they are more likely to be coupling caps. They seem too small to be for cathode bypass.

Mike
06-05-2009, 16:13
What I'm looking for in sound is more like open, detailed, clear, etc. Something that will let ALL of the sound of my tube choice show through.

I'd be tempted to suggest polypropylene caps, something like the Soniqs SAX type from WD should do the trick! :)

http://wduk.worldomain.net/acatalog/SONIQS_SAX_Polypropylene_Capacitors.html

Cheers...

alb
06-05-2009, 17:18
Interesting that an amp named TRV-35SE, should turn out to a push pull. Anyway it looks well made with decent components.
They probably are coupling caps and it looks as though you have enough space in there to experiment.
Another suggestion would be Dynamicaps.

James G
06-05-2009, 17:25
Thanks guys for the info.

Mike, from the description they certainly sound like what I'm looking for. In changing the cap type, should I keep with the exact same values?

I found this link from a Japanese audio site and the guy has the same amp as I do with Vitamin Qs loaded, but his are .1uF. Now I'm even more confused. :confused:

http://community.phileweb.com/mypage/entry/642/20081208/8861/

James G
06-05-2009, 17:37
Interesting that an amp named TRV-35SE, should turn out to a push pull. Anyway it looks well made with decent components.
They probably are coupling caps and it looks as though you have enough space in there to experiment.
Another suggestion would be Dynamicaps.

Heh, I know what you mean. ;)
I think the SE is for Special Edition. It was originally released as TRV-34SE and only 500 made as like a 25th anniversary commemoration. But then he got such good feedback that he decided to keep going with it and just changed the name a bit to differentiate the anniversary ones. If I understand correctly. Well, something like that.

Hmm, the Dynamicaps are described as lush, smooth and warm. I don't doubt they are excellent though.

I'm having a terrible insomnia night. Too much coffee today. :mental: Gotta get some rest. I'll check back tomorrow evening.

Mike
06-05-2009, 17:49
In changing the cap type, should I keep with the exact same values?

I found this link from a Japanese audio site and the guy has the same amp as I do with Vitamin Qs loaded, but his are .1uF. Now I'm even more confused. :confused:

I would stick to the values as fitted, it could be that this guy has other mods or has been altering values to suite his own taste.

I seem to remember Sprague VitaminQ caps being popular with guitarists for that 'vintage Gibson' sound, so they are possibly quite 'flavoured'.

alb
06-05-2009, 17:50
I found this link from a Japanese audio site and the guy has the same amp as I do with Vitamin Qs loaded, but his are .1uF. Now I'm even more confused.

0.1uf either way is unlikely to make any difference. Just make sure they match or exceed the originals with regard to voltage.

Ali Tait
06-05-2009, 23:12
Another option would be teflon SCR's.You can get these from hificollective.Not cheap but very good indeed IMHO.Give just the sound you are looking for.Another contender would be Audionote coppers.Another excellent cap.

James G
07-05-2009, 15:03
Well for the price and seeing as how this is my first experience with these kinds of caps, those Soniqs SAX are looking like they might be the ones.

I'm thinking of moving up from .22uF to .47uF to stiffen up the bass. The amp is a bit on the bass shy side. Any thoughts? Big mistake? :scratch:

James G
09-05-2009, 14:01
Unfortunately World Designs UK doesn't ship to Japan, and I couldn't find any other dealer for the Soniqs SAX.
I have ordered the Dynamicaps instead. If they even come remotely close to the claims on the TRT-Wonder website, I will be one happy camper. Hopefully I will get them by next weekend.

From the manufactuer:

DynamiCap key sonic features:



Makes music, voices, and soundtracks come ALIVE!
More dynamic power, force, and impact.
Clearer, more transparent, airier, more open, and faster than any other capacitor.
Richer body and warmth, giving you more of music's solid, tactile reality.
More musically accurate and natural - hear the true natural timbre and subtle textures of music and voices. You'll hear better the wooden sounding board of a piano or cello, the large cavity of a bass viol, the fact that a singer has a real body and chest (not merely a small mouth).
Subtle liquidity, giving music a very natural quality.
Reduces the sonic glare or brittleness found in many CDs and film soundtracks. DynamiCap cuts through glare like a polarizer, to reveal more of the true musical, instrumental, and voice information.
More revealing of music's inner detail, yet also more relaxing and less fatiguing for long term enjoyment.

http://www.trt-wonder.com/page5.html

Ali Tait
09-05-2009, 14:56
I haven't tried them myself,but I know several who have and they are very happy with them.Definately one of the better caps out there.

Mike
09-05-2009, 15:00
Unfortunately World Designs UK doesn't ship to Japan, and I couldn't find any other dealer for the Soniqs SAX.


That's a shame...

If you want some in the future just let me know, I'd be happy to forward them on.

James G
09-05-2009, 15:40
That's a shame...

If you want some in the future just let me know, I'd be happy to forward them on.

Thanks Mike, that's really nice of you to offer. Since becoming a fan of Marshall amps a long time ago, I've had a soft spot for British audio, but I could never afford the really good stuff.

I extend the same offer to you if you have trouble getting something from over here. :peace:

James G
17-05-2009, 07:29
Well, I've got the Dynamicaps in now. I must say that they have made a big change in the sound. Bigger than any other tweak I have done so far.

It certainly has opened up the sound by a large margin. Much airier and brighter than the darkish and warm paper/oil caps. Now it seems like I'm starting over with a new amp. Trying to work out which valves sound better, cables, etc. The setup I was running before does not synergise the way it did before.

But I can hear the difference in valves much more. I can now understand the charm of 5751's, where they seemed dull and lifeless before. But for certain I have a clearer window to the music and hearing things I didn't before. Just have to work out the synergy again.

Mike
17-05-2009, 08:23
Hi James,

Sounds like a good result! :)

I'd let them burn in and settle down a while before playing around too much though, they may well improve forther over the next few days or even weeks.

Cheers...