Tube recommendations

[mobile homeless]

You really dont hear much about Brimar 2A3 tubes; I have never heard them but would sure like to. As I recall, I cant really ever remember reading much about them as the US brands get more exposure in the 2A3 NOS market with the famous and VERY expensive Monoplates from the 30s coming in as VERY valuable. When you see one of those "Cunninghams" go on ebay, it get very pricey. There are a load of them under different names which is where you get the bargain in the monoplate field.

[edwardre]

Hmmmm.....ok then, what the majority of you have said makes sense. While 're-capping' my tube preamp and prior to starting on the tube amp, I was testing each 'enhancement' prior to going on to the next set of caps to replace. As the tube amp was partially disassembled and inop, I ran the preamp into my ss Bryston 2B-LP 'test bed' amp to gauge the effects each set of caps changed made. Then when I finally moved over to the tube amp, I noticed that the difference between it and the ss Bryston were very subtle as compared to the difference between the ss pre and the tube pre. I just thought that the Bryston ss amp was 'warm and tubelike', or that the ST70 was a little 'raw' where tube amps are concerned.

Thanks for the insight.

[edwardre]

Ooops! Above post posted to the wrong topic. A thousand pardons.

Craig, thanks for the offer. I would be delighted to attempt a 2nd bias pot 'enhancement'. Yes, the ST70 supplies negative V to the output tubes. It did have the selenium rectifier but I replaced it with a diode. There is plenty of room to fit and I will send you the schematics in an e-mail.

MH - I received and installed the Solen Fast-caps last evening. PU. Even after several hours of the disputed 'break-in' they were all but unlistenable. To me, the describer 'harsh' refers to an overemphasis on upper mid to high freqs that lends itself to quick fatiguing. Not only are the Solens (in this app) 'harsh', but they are likewise 'hard' across the entire range and completely de-emphasise any semblence of bass. With the bass cranked to the pin for both channels, it was/is still sadly lacking. There's $7 tossed into the toilet. With that in mind, what would be a good coupling cap? Other than $20/per Jensen oils!!! Not sure if I want to invest $80 for this enhancement quite yet.....

Thank

[mobile homeless]

Edwarde - Well, I tried to warn you on this about three threads back. What is really amusing is the fact that I spent hours arguing with a few on this board about cap and quality and the sonic differences and was met with a wall of distrust on the issue last year. I will say again, they DO make a difference, especially in the coupling region. And moving UP in size like a good many here are doing is not as wise was we all once thought it was as it WAS common practice but I now disagree. Perhaps get a shade over the value but not much. Increasing the voltage usually gives a more hearty cap so that is fine although now people are wondering about this as well sonically.

Enough prattle.... How many caps do you need? You know why? If it's four or so, GO WITH THE JENSEN/ANGELA/AUDIONOTE Copper Foil Oil caps. I think they are the cheapest at Angela Instruments. It is WORTH the money, I am telling you as there is nothing that will make your amp more sweet and musical, while STILL being VERY revealing and transparent, with an openness combined with a harmonic richness. Listen, you have put A LOT into this amp, so why not put these caps in if it will aid in bringing the sound you want? Take the FAst Caps and toss them to the wind - the copper foil oils are the ticket with that amp, especially with the comments I have been hearing from you. They do take over 100 hours (yes, you read that right) to break in, but once done, they are SO open and alive, while still being warm.

As I said, Angela has the cheapest versions - they are Jensens but with the Angela name. Get the COPPER FOIL 630v version. You will not regret the $80 spent (that only a good dinner out).

If you positively DONT want to do this, let me know. But I say it is WELL worth it, especially considering the other options are not exactly cheap either.

You wont be sorry. If Jensen are ony a $ or two more, go with them but I am almost positive the Angela is the same. I once heard they got seconds but you know how that is. Even so, I think the Jensen at some places is within $4 or so.

kh

[NOSValves]

Mobile,

Why do you say that just the output coupling caps effect the sound ?? I have a scope and on my Scott amps all the coupling caps in it some 12 to 16 carry wave forms thru them so I would say they all effect the sound wouldn't they ?? When taking this into account your talking some mega cheese to install the above mentioned caps. With intergrated amps almost all caps hooked to any of the tubes effect the sonics of the music don't they ?

Craig

[mobile homeless]

#1. The ST-70 is not an integrated amp so the cost is not as prohibative.

#2. I said "coupling" and not only "output coupling."

Where did I only specify output coupling? All the coupling caps have an impact to the sound as I have said in about every post I have made. I think the ST-70 has only 4 coupling caps total, so the expense is worth it.

[NOSValves]

Mobile,

I was just trying to get your opinion on the preamp section and whether you feel they make a big difference there. I had a conversation on the phome with MDeneen a few weeks ago and he stated in his ST-70 type amps he doesn't think the High Dollar Audiophile caps are worth the expense he said they make little or no difference.

Craig

[mobile homeless]

As you know, mdeneen and I dont agree on this aspect as I DO think caps can make a difference. Sometimes the difference is slight, sometimes not. See the comments above when the Solen Fast Caps are installed, or the 716p for that matter. I dont know, it is gear dependent. And you can believe what you want here. I have found otherwise in a variety of gear. I think if you dont have your system setup optimally, some of these differences will be hard to ascertain. Also, some arent as sensitive to these changes. Regardless, I am not here to start a debate yet again on parts. I went through this all last year and the "parts is parts" philosophy is well documented. I DO believe that some parts are overrated and that certain parts that work well in one application, dont always transfer to another.

You, and everyone else, is free to put in what you like. And you are right, if you cant or dont hear a difference, then it is surely money not well-spent. I have found otherwise but that is just my experience.

I do agree with you that the coupling caps in the input stage are important as well. I also think that caps like Solens are best left out of the coupling region. I dont like using the word "audiophile" either. Lumping expensive parts in this category misses the point. In the instance of the Jensen/Audio Note Copper Foils, while they MAY be expensive, I think they are WELL worth it in certain applications, especially in critical coupling regions. Obviously, in a vintage integrated with a host of caps and little room, price and space are an issue.

[NOSValves]

Mobile,

The reason I even brought this up is that I myself think the Russian Paper in Oils I've been using throughout the Amps I've been doing make a big difference (althought they seem to take a long time to break in). I sent some of these to Mark and we had a breef discussion on them. He tested them out and said he thought they were well built and he liked them. But he also said that he thought they didn't really make a big difference sonically over Orange drops in his ST-70 based amp. but they only have 4 like you said. Then I said well wouldn't you think that in a intergrated amp with 14 to 20 of these caps that they could make a much more drastic difference and he said absolutley. I really like these PIO's I've been using. I like them so much I paid the long dollar and bought like 600 of them a various values !! The reason I invested in so many is there old russian Military spec and sooner or later the availability is going to dry up. Its already hard to find the .047 and .1 MFD's . I now have them in .015, .022 , .033 , .047 and .1 MFD all @400 volt and above to rebuild amps with. I'm not a big believer in upping the Voltage rating. If the parts 40 years ago lasted this long at 400V rating what the heck do you need higher voltage ratings !!

Craig

Craig

[mobile homeless]

Although I respect mdeneen a lot and we have come to an understanding with each other sharing mails and some circuit talk (we have been talking about my old A-4 EL-34 amp), I dont understand how he could say that those vintage paper in oils did not make much of a difference in the ST-70. If there is a bigger difference, I cant think of much more than comparing vintage oils with something like a 716p. The sound difference WILL be noticable even if run through a pair. Now, some will not like the sound of these oils, just like the distaste by many for the Vitamin-Q oils, but there IS a difference. I dont belittle people any more for not hearing this or not having a system setup for it. Many refer to measurements in relation to cap sound as well. Regardless, the difference between oils and film/poly caps is not that subtle if you really listen to the music. Or course, they do have to be broken in but I think ONE Jensen in the crucial coupling region has the ability to impart some of the characteristics. Cary has gone with these caps in upgrades to ALL their products from preamps to ultranlinear, to air-gapped SET designs, where the difference can be profound.

I have never heard the vintage oils you talk of but am still wanting to try them. Most people that have heard both the Vitamin Q vintage oils prefer the Copper Foil Oils in big way saying they are less syrup-like and more open. Still, some dont like oils, regardless. But there IS a distinct sonic difference between oils and ANY poly/film/metalized etc cap.

Mdeneen and I discussed the possibility of putting oil caps in the power supply, something I really want to try next as I have head a load of positive on this. They are BIG bastards, however.

I have a host of film/foil MIT RTX caps in my preamp and they are extremely neutral, quick, detailed, clean, etc. But the Audio Note Copper Foil caps have this rich musical tone that is such a rare combination in that there is sweetness AND great resolution. You dont get the rich harmonic sound at the expense of a too sweet and thick a presentation.

Still, in some circuits, people do prefer other caps.

[Deang]

I now have both the stock AE-3 and the DJH version.

The stock unit uses film & foil, solid state rectification, and is running a pair of Redbase 5692's.

The DJH version uses the Jensen copper foil paper in oil, tube rectification, and is running a pair of Sylvania chrometops.

Both of the preamps sound very good, but they do not sound like the same unit.

I bring this up because it certainly seems to me that the summation of the parts used accounts for the signature of the unit. I mean, every part will make a difference, and changing them out should change the sonics to some degree.

The stock AE-3 sounds great, and is a perfectly easy unit to listen to -- but the DJH version of the same unit, using the copper foil/oils has a warmer, richer tone, more "air", and the bass seems to have more authority.

$80 doesn't seem like much money considering the potential improvement in sonics.

In the stock AE-3, I know I would like to replace the film and foils with the oils, and the electrolytics with film and foils -- if I can ever get the DQ's back together again:)

Gee, I wonder how a couple of those Jensens would sound in my RF7's:)

BTW -- Check out this thread:

http://www.audioasylum.com/forums/welborne/messages/1783.html

[edwardre]

Yeah, it certainly appears that this topic has been beat to death in about every audio forum known to man with the bottom line being the bottom line with just about everything audio.....personal preference. I thank you all for the input and for your patience in 're-hashing' for this tube-newbie.

I have to say, I really enjoy this whole tube thing. This is turning out to be one of the most enjoyable passages of time I've had in a while as it pertains to the joys of audio. Everything being discreet (component wise) makes for practically unlimited 'fiddling'. You could never ever in a million years tinker with SS to this degree. It seems like every single thing I do to it makes some sort of audible difference. I doubt I will ever be truly 'done'.

Pheasant season is looming for us Californians. Early this summer, I purchased a 'project' travel trailer for bird hunting season. It's a real piece of work. Dry rot everywhere. As a result, I've spent endless hours in the garage restoring it. This affords me endless hours of music listening, as the tube test bench shares the garage. My MO of late has been to come home from work, swap a few caps, resistors, etc on one or the other (Preamp or amp) then spend several hours listening. In fact, I've just come in (it's 12:30AM-ish). Today's 'swap' was to replace two of the last 4 remaining caps that were stock. The 82pF's in the general reigon of the main output coupling caps. I have a bunch of Mallory SX series polystyrene caps that I got en masse with the orange drops. Just so happens there were a handful of 82pF's. I matched up 2 and installed. (The old stock ones measured out to be about 65pF). These seemingly insignificant caps made a huge difference. Almost as much as the main coupling caps. The improvement was very noticeable. Rich sound with no harshness. I have noticed that I like the polystyrenes over the polyprops. They are detailed and have no harshness whatsoever. "Airy". Seem to increase imaging.

MD - It is now apparent that the Jensens will have to be tried! Thinking of ordering up 4 this coming week. For now, those Solens are out. I also cut way back on the size, from the 1uf Solens back to the .1uf Black Cats that were originally there, in parallel with 2 .25 Orange Drops for a combined total of .6uf. They are likewise matched within 1%. This is a fairly good sounding combo that seems to bring out the best of both types. Most of the rest of the Orange Drops are being replaced, by the pair, for the polystyrenes. But like you said, everything in the signal path impacts the sound, some subtle and some more noticeable. There are some OD to Polysty swaps that sounded worse. Anyway, onwards.

Have you had any experience with the polystyrenes? They certainly have a different sound than the polypropalenes.