[FishHead]

Is now a good time to say that we've been talking about a Torpedo 2 for a while? We've prototyped a few designs. The idea is not to make an incremental improvement, but to make a totally different amp with a different topology and different tube type in a similar form factor while reusing some of the major parts. So it won't render the T1 obsolete which is not going anywhere, and it will likely cost a bit more. Hopefully we'll have something concrete this winter/spring?

:veryevil:

Happy New Year!

 

[OJNeg]

  The problem is that all listening is subjective.
Personally, I find the 6J6 type tubes a little 'harsh'.
The one exception I've found is the Mullard M8081 / CV4031 which I feel is the best of the 6J6 types.
I've been swapping round between a pair of Valvo E90CC's, SQ (special Quality) Miniwatt E90CC's and a pair of RFT ECC960's.
For my setup and my ears the Miniwatt and the RFT's are the best.  I can't tell them apart.
 
The Torpedo is a fantastic amp.  I love it!!!
 
Many thanks to dsavitsk and tomb for providing us all with hours of entertainment.

 
 
I haven't tried these. Did you grab them off ebay or a more reliable vendor?
 

 
Thanks for the kind comments - you've given us a lot!!
 
I mostly agree with you and understand the impression that the 6J6 gives a better bass slam, but you are correct that they are a little "harsh."  That's because the distortion is a bit higher and you'll hear it on loud and elevated multi-voice passages.  I've also purchased the Mullard CV4031's that you've recommended, but I'm not certain that they're that much better than a good Sonotone 6J6W or similar.  That's only my opinion, though.  I have some ECC960's but have not got around to trying them, yet.  One other tube that people might try as a somewhat cheaper alternative to the E90CC is the E92CC.  It's almost an identical tube with slightly different ratings.  It has a tad bit more distortion than the E90CC, but is still in a much better class than the 6J6.
 
That said, a little perspective is perhaps in order: even with the 6J6, the sound quality far surpasses other tube amps in its price range.  Realize that the 6J6 is still available for $1 (ESRC Tubes until tomorrow!) or a bit more at most places.  This final rendition of the Torpedo has taken some time and a lot of work from Dsavitsk - even Morgan Jones and Kevin Gilmore helped along the way to pinpoint/solve the noise issue.  As a result, I can finally brag: the Torpedo is truly one of the finest tube amplifiers available.  The fact that it's available in PCB form as a DIY kit makes it even more valuable and unique, IMHO.
 
Anyway, I know I'm a MOT, so my motives and opinions are supposedly questionable and biased, but still ... it's wonderfully exciting to be able to supply something from Beezar that performs at this level of quality.

I have to ask, are we talking measured distortion here or are you using distortion as a sonic descriptor? I ran RMAA tests on the different tube variants and according to my test the tubes with highest gain (6J6 = 38, E92CC = 45, etc) seemed to measure the best in terms of THD. Although I do agree that the E90CC sound cleaner and more refined, regardless of measurements. Maybe the results change with lower impedance loads though.
 
Other than that I have to concur that the Torpedo is the best SET amp you can find at the given price. I might differ in that I feel the stock caps are holding it back a bit. Although they're not bad sounding caps in an absolute sense. (Probably way better than your average electrolytic). My experience tells me that a better coupling cap takes this amp above and beyond the competition. The way I see it, after that's taken care of, you can roll tubes to your delight and the Torpedo will respond very well to changes. The chase never ends, sonic bliss is always around the corner of course :rolleyes:
 
Along the same lines, I'm curious as to what the Torpedo 2 can bring to the table.

 

[UKToecutter]

I got them through eBay.
The seller was yitry.
Item number 260747088812

 

[tomb]

 

  The problem is that all listening is subjective.
Personally, I find the 6J6 type tubes a little 'harsh'.
The one exception I've found is the Mullard M8081 / CV4031 which I feel is the best of the 6J6 types.
I've been swapping round between a pair of Valvo E90CC's, SQ (special Quality) Miniwatt E90CC's and a pair of RFT ECC960's.
For my setup and my ears the Miniwatt and the RFT's are the best.  I can't tell them apart.
 
The Torpedo is a fantastic amp.  I love it!!!
 
Many thanks to dsavitsk and tomb for providing us all with hours of entertainment.

 
 
I haven't tried these. Did you grab them off ebay or a more reliable vendor?
 

 
Thanks for the kind comments - you've given us a lot!!
 
I mostly agree with you and understand the impression that the 6J6 gives a better bass slam, but you are correct that they are a little "harsh."  That's because the distortion is a bit higher and you'll hear it on loud and elevated multi-voice passages.  I've also purchased the Mullard CV4031's that you've recommended, but I'm not certain that they're that much better than a good Sonotone 6J6W or similar.  That's only my opinion, though.  I have some ECC960's but have not got around to trying them, yet.  One other tube that people might try as a somewhat cheaper alternative to the E90CC is the E92CC.  It's almost an identical tube with slightly different ratings.  It has a tad bit more distortion than the E90CC, but is still in a much better class than the 6J6.
 
That said, a little perspective is perhaps in order: even with the 6J6, the sound quality far surpasses other tube amps in its price range.  Realize that the 6J6 is still available for $1 (ESRC Tubes until tomorrow!) or a bit more at most places.  This final rendition of the Torpedo has taken some time and a lot of work from Dsavitsk - even Morgan Jones and Kevin Gilmore helped along the way to pinpoint/solve the noise issue.  As a result, I can finally brag: the Torpedo is truly one of the finest tube amplifiers available.  The fact that it's available in PCB form as a DIY kit makes it even more valuable and unique, IMHO.
 
Anyway, I know I'm a MOT, so my motives and opinions are supposedly questionable and biased, but still ... it's wonderfully exciting to be able to supply something from Beezar that performs at this level of quality.

I have to ask, are we talking measured distortion here or are you using distortion as a sonic descriptor? I ran RMAA tests on the different tube variants and according to my test the tubes with highest gain (6J6 = 38, E92CC = 45, etc) seemed to measure the best in terms of THD. Although I do agree that the E90CC sound cleaner and more refined, regardless of measurements. Maybe the results change with lower impedance loads though.
 
Other than that I have to concur that the Torpedo is the best SET amp you can find at the given price. I might differ in that I feel the stock caps are holding it back a bit. Although they're not bad sounding caps in an absolute sense. (Probably way better than your average electrolytic). My experience tells me that a better coupling cap takes this amp above and beyond the competition. The way I see it, after that's taken care of, you can roll tubes to your delight and the Torpedo will respond very well to changes. The chase never ends, sonic bliss is always around the corner of course :rolleyes:
 
Along the same lines, I'm curious as to what the Torpedo 2 can bring to the table.

You'll have to ask Dsavitsk.  I think it was a simple matter of mu values that are different when applied to the theoretical circuit calculation.  My listening experience has proven this out, but I suppose that could be a self-fulfilling delusion.

 

[dsavitsk]

Along the same lines, I'm curious as to what the Torpedo 2 can bring to the table.

If nothing else, the new one is different for the sake of being different not only from the "1", but also from anything else I am aware of. Beyond that, and without getting into specifics, it has some features to recommend it such as lower impedance for driving the transformer, lower distortion, some nice tube rolling options, lower heater current which translates into lower noise, etc.

As for tube rolling the original, you're asking the wrong guy. I have not played with many different 6J6 variants.

 

[FishHead]

Is it too early to start a T2 thread?

 

[tomb]

Is it too early to start a T2 thread?

Maybe ... you guys please remember that it took us over 3 years to get to this point.

 
I have every confidence in Dsavitsk, but stuff happens ...

 

[dsavitsk]

I have every confidence in Dsavitsk, but stuff happens ...

Ha! This is Tomb's very polite way of saying I have been pathetically slow lately I wouldn't start a thread just yet. We'll announce more when I get my act together.

 

[NuClear235]

Please at new models add space in case in area at pot possition. To be possible to change pot to Attenuator:
http://www.ebay.com/itm/Dale-23-Step-Ladder-type-Attenuator-Volume-Control-Log-50K-Ohms-Stereo-/321211481302?pt=Vintage_Electronics_R2&hash=item4ac9b23cd6

 

[JamieMcC]

I used the RN55 series Dales in one of my attenuators  (Glass-ware A5) they have been a joy to listen through.

 

[tomb]

I don't want to be discouraging about the attenuator suggestion, but let me offer two points:
 
1. Dsavitsk used the Alps RK27 for his top-of-the-line, Summit Hi-Fi L-2.  He also used them in the Black Diamonds.  There are numerous other instances of extremely high-level amps, including balanced and electrostatic, using 4-channel versions of the RK27.
2. The Torpedo PCB has mounting holes all along the perimeter.  Plus, Beezar has always offered the PCB's for separate sale.  So, you could build your own case design and off-wire anything you can dream up.

 

[HiGHFLYiN9]

  I don't want to be discouraging about the attenuator suggestion, but let me offer two points...

Very valid points. There are no limits with your own chassis  

 

[NuClear235]

It was just the tip for new future version of amp.
-bigger space around pot
-Add possibility that LEDs under Tubes will start glow after end delayed start of relay.
So will be shown, that amp is ready.
But Center LED stay permanently powered on to be shown that amplifier is switched ON.
(Maybe is Delay circuit not used because output transformer.)

I have MiniMax not Torpedo. There is really little space around Blue Velvet Pot.
But Your case is so sexy-make my own I want still not

 

[jboehle]

Quick question: are the build instructions on the Torpedo website all up to date?  I'm about to start my build but it's been a while since I read through this whole thread.

 

[tomb]

  Quick question: are the build instructions on the Torpedo website all up to date?  I'm about to start my build but it's been a while since I read through this whole thread.

The last page in the series of construction articles is completely up-to-date with the newest PCB's:
http://www.diyforums.org/Torpedo/TORPEDOconstruct11.php
 
The additional notes at the bottom of the page sum up all of the changes.