[flaming_june]

However, is there any truth to low durability of Shuguang tubes?

 

[Maxvla]

Quote:

 


solid state recification offers virtually zero voltage sag compared to tube rectification so the sound will be more dynamic...
but, you should ask jack of wooaudio if it's alright for the wa6. solid state rectifiers put full voltage immediately to the
cathode of the output tubes without letting it warm up to put up an electron cloud. this will cause cathode stripping and
cause premature death to the output tubes.

How substantial is this difference? I ask mostly because I'm curious as I've got a Little Dot MKVI that is a balanced tube amp using solid state rectification (OTL). It uses 6080/6AS7G (4) and 6H9C (2) tubes. One of the strengths I've always enjoyed about this amp is how dynamic it is, perhaps this is why.

 

[Clayton SF]

Quote:

solid state recification offers virtually zero voltage sag compared to tube rectification so the sound will be more dynamic...
but, you should ask jack of wooaudio if it's alright for the wa6. solid state rectifiers put full voltage immediately to the
cathode of the output tubes without letting it warm up to put up an electron cloud. this will cause cathode stripping and
cause premature death to the output tubes.

Has anyone written to or heard from Jack about ss rectifiers in his amps?

 

[che15]

I am also interested on ss rectifier for my wa6.

 

[che15]

Hay guys I haven't posted for awhile to busy at work


After reading the posts about the expensive 6SN7RP their is a pretty much unknown tube the 7AF7 round plate.


It has the same specs as a 6SN7 with a little lower gain 16 vrs 20 for the 6SN7 this might make it a better candidate for the WA6.


The 6DE7 has lower gain than a 6SN7.


I tried these in a 22 and sounded pretty darn good maybe not as good as my 6F8Grp but I don't have a WA6 to try these in.


If somebody that has a WA6 and would like to try the 7AF7 I will send a pair of tubes and adapters for a try and let us know how they sound.


The 7AF7 only costs $11.10 at Antique Electronic supply and as far as I know all brands are Round plate.


Let me know if anyone has interest.  Glenn

Hello Glenn I would love to compare the new tubes to the 6sn7 that you made adapters for.
Thanks

 

[AustinHorn]

Hey Guys,
 
Here is the answer I got from Jack regarding the use of the ss rectifier in my Woo6 Max:
 
"SS rectifier has lower internal resistant and thus output higher voltage. It could possibly damage the tubes. I have not expereienced it in real application so cannot come to a final conclusion. However, there is no need at all to use solid state rect while tube rect produce better sound."
 
Well, he should know.  I do know this now, if I do use it some more, I'll use it with tubes other than my $300 TS tubes.  I can afford to risk $5 or $10 tubes, but that is about it.  At least he didn't say anything about any risk to the amp itself.  I also ran this buy my neighbor who is a Proff of Electrical Engineering up at UT Austin, & also an audio buff.  He didn't feel like there was much of a risk at all to the tubes themselves & certainly none to the amp, though he agreed to me he might think twice before using NOS tubes with it, especially expensive ones. He felt newer tubes wouldn't have any problems.  He said my ss. rectifier is a new tube & just doesn't have the power to hurt modern day amps, but older tubes.... he's not so sure. But that kinda shoots my idea in the foot to use it to do all my casual listening & save the Sophia/EML for more serious sessions.  I'm going to turn one of the ss rectifiers over to my neighbor & let him take it up to school & do more testing.  I'll pass on any info he provides. Until then, if I use them at all I'll use them with a couple of JJs or some of the cheaper, NOS tubes.  Anyway, FYI.  I'll follow Jacks advice unless I learn more from the coming tests.
 
But damn those things really sounded good with those matched TS tubes!!!!!

 

[Xcalibur255]

Quote:

I'm also hearing fingers plucking guitar strings.  How detailed can these get?

 
This was the most rewarding thing about switching to the 6SN7, hearing these kinds of details.  Actually the best tube I have heard for highlight guitar strings and their associated textures/details is the Tung Sol mouse ear tube.  The almighty round plates achieve the same level of resolution, but the mouse ear seems to specifically call attention to it where guitar is concerned, making it easier to take in.  I honestly think the round plate is presenting the sound more accurately, but the mouse ear will spoil a person who loves to listen to guitar in general.
 
Each 6SN7 tube I've tried seems to have one thing it is particularly good at.  The RCA greyglass was piano.  The mouse ear was guitars.  The Sylvania bad boy was violin (as of yet nothing has impressed me more than this instrument with this tube, I melt into my chair each time I hear it).  Then I got the TSRP which breaks the pattern by being equally good at everything.  The downside is it is kind of fun when a tube calls out a particular instrument as special, even if it is not faithful reproduction and the round plate will not do this.  I was actually kind of glad, because it means my other tubes still serve a purpose.

 

[Silent One]

Quote:

 
This was the most rewarding thing about switching to the 6SN7, hearing these kinds of details.  Actually the best tube I have heard for highlight guitar strings and their associated textures/details is the Tung Sol mouse ear tube.  The almighty round plates achieve the same level of resolution, but the mouse ear seems to specifically call attention to it where guitar is concerned, making it easier to take in.  I honestly think the round plate is presenting the sound more accurately, but the mouse ear will spoil a person who loves to listen to guitar in general.
 
Each 6SN7 tube I've tried seems to have one thing it is particularly good at.  The RCA greyglass was piano.  The mouse ear was guitars.  The Sylvania bad boy was violin (as of yet nothing has impressed me more than this instrument with this tube, I melt into my chair each time I hear it).  Then I got the TSRP which breaks the pattern by being equally good at everything.  The downside is it is kind of fun when a tube calls out a particular instrument as special, even if it is not faithful reproduction and the round plate will not do this.  I was actually kind of glad, because it means my other tubes still serve a purpose.

Thanks to Glenn's adapters, the 6SN7 tubes yielded two surprises for me: 1) Hearing the kind of details you mentioned.  2) I couldn't believe how cool my Woo ran. With the stock 6EW7 tubes in my WA6SE, the amp ran hot and summertime didn't help. And now? With 6SN7 tubes now glowing, my Woo doesn't even get warm!

 

[matthewh133]

Sorry for the noob question. Are these the 6SN7 tubes you guys are speaking of?
 
http://cgi.ebay.com.au/New-Production-Matched-Pair-Tung-Sol-6SN7GTB-6SN7-Tubes-/350364761296?pt=Vintage_Electronics_R2&hash=item51935dfcd0
 
I am looking at getting a WA6 when the opportunity arises and it seems these should be great with the Sophia Princess.

 

[SpudHarris]

No, those are the new production Tung-Sol 6SN7's. The Tung-Sols we all rave about are the Black Glass/Round Plate 6SN7's. I haven't checked of late but they do crop up on e-bay but they are rare and cost a fortune. My second set were $380

 

[matthewh133]

Wow. Redonkulous! Here I was thinking the Sophia would be a pricey investment. Might have to find a cheaper pair to accompany it for starters

 

[Skylab]

Quote:

 
Here is the answer I got from Jack regarding the use of the ss rectifier in my Woo6 Max:
 
"SS rectifier has lower internal resistant and thus output higher voltage. It could possibly damage the tubes. I have not expereienced it in real application so cannot come to a final conclusion. However, there is no need at all to use solid state rect while tube rect produce better sound."
 

 
Well, I'm glad Jack said it first.  I cannot imagine why anyone would want to use a SS rectifier.  They sound TERRIBLE.  A buddy of mine replaced the 5AR4 with a solid state rectifier in this modified Dyna Stereo 70, and he was NOT happy with the result.  It sounded worse, and made the whole amp bright sounding. 

 

[hodgjy]

I've rolled in several TS power triodes, and the description you mentioned fits the appearance of at least half of the TS tubes I've tried.  The rattle is just a little glue that broke off that used to hold the base to the glass.  Or, it is a small piece of glass that broke off when the base was fitted to the glass.  This is also common with tubes because of little imperfections associated with the glass blowing.  Whatever the case, it is not inside the tube, so you have nothing to worry about.  Plus, you have to figure that these tubes are OLD, and probably spent a lot of time in someone's musty and damp basement, so glue failure is common.  I have a tube or so with a loose base.  No worries at all.  Just make sure you always handle the the tube by the base, and not the glass, and all will be ok.  Your tubes won't die any sooner (or later) just because of a base glue issue.
 
Quote:

Guys, I just received my set of TS BGRP's from Walt (e-bay) and wandered if you could advise me.....
 
Tube 1 is just perfect and does look brand new. Tube 2 still looks nice (although slightly taller than tube 1) but has a terrible rattle as though there is something loose inside, also the base is ever so slightly loose

I have tested them and dispite the issue with tube 2 they do sound amazing. Will the issue with tube 2 shorten it's life do you think? I haven't written to Walt yet as I thought I'd get your take on it.
 
It's a little disapointing really considering the cost. Also tube 1 is Dec 1942 and tube 2 is Nov 1942. Again, disapointing......

 

[Clayton SF]

 
Quote:

Hey Guys,
 
Here is the answer I got from Jack regarding the use of the ss rectifier in my Woo6 Max:
 
"SS rectifier has lower internal resistant and thus output higher voltage. It could possibly damage the tubes. I have not expereienced it in real application so cannot come to a final conclusion. However, there is no need at all to use solid state rect while tube rect produce better sound."
 
... I'll pass on any info [Jack] provides. Until then, if I use them at all I'll use them with a couple of JJs or some of the cheaper, NOS tubes.  Anyway, FYI.  I'll follow Jacks advice unless I learn more from the coming tests.
 
But damn those things really sounded good with those matched TS tubes!!!!!

Thanks. It's always good to find alternatives to expensive NOS tubes. I found some ss rects for $9.95 - $14.95. I guess now I have to match them with TS tubes to hear what you're hearing.

 

[Skylab]

You can get a NOS 5U4GB for $25, or used/tested ones for under $10!  I can almost guarantee that it will sound better than any SS rectifier.