I am thinking of springing for a pair of 2A3 mesh plates in the near future as my new dc coupled 2A3 amplifier is now operating and with some component replacements will be finished soon.
I am interested in comments from people who are using or have used tubes by this manufacturer.
I am also interested in comments on the 45 and 300B mesh plates as I have amps that can use these as well.
The online tour of the factory hosted by diyHifi looks pretty impressive.
I am interested in comments from people who are using or have used tubes by this manufacturer.
I am also interested in comments on the 45 and 300B mesh plates as I have amps that can use these as well.
The online tour of the factory hosted by diyHifi looks pretty impressive.
hi kevin, i've had a chance to put in a TJ Mesh on my 2A3 and didn't like them. They sounded slow- not to my liking. Seems to lack the grunt and snap I am looking for. I'm better off with Sovtek 2A3 for that matter. i am now using a bi-plate RCA 2A3 I got as NNB (NOS No Box ) for PhP7,000 here in the Philippines. It has the speed, grunt and snap but with smoother presentation.
(my music is from classical to heavy metal)
(my music is from classical to heavy metal)
I have the Yamamoto A-08 45 SET, and I have been testing with following three tube sets the last year:
NOS RCA 45
TJ Mesh 45
EML Solid Plate 45
The EML Solid Plate 45 betters the two other in nearly every respect. Less hum, more defined low end and better transparency. The TJs sound too lush for my liking. I also get a smidgen more hum with the TJs. These are my findings when used in the A-08. You might get other results in in another amp, but I suspect that the sonic signature of the tubes would still be there.
NOS RCA 45
TJ Mesh 45
EML Solid Plate 45
The EML Solid Plate 45 betters the two other in nearly every respect. Less hum, more defined low end and better transparency. The TJs sound too lush for my liking. I also get a smidgen more hum with the TJs. These are my findings when used in the A-08. You might get other results in in another amp, but I suspect that the sonic signature of the tubes would still be there.
Hey KEvin K: I've been using a pair of TJ meshplate 2A3s in my bottlehead paramours for about 1.5 years now. I love them and they've been extremely reliable. I have the opposite experience from Arnold, to my ears the TJs are well worth the price differential over the sovteks (shrill and harsh) or the valve arts (slow and soupy).
best, Kevin G
best, Kevin G
I was pretty much settled on the TJ's until I picked up a pair of Shuagang 2A3C's. Stuck them in to make sure they worked, and never looked back. I've accumulated RCA's, TJ's, Valve Arts, Canadian Marconis and Raytheons - but the 2A3C's just never seem to come back out of the circuit for very long. Not considering that they are priced comparable to a Valve Art (i.e they're inexpensive for a 2A3), I just really enjoy them in my Paramours.
Hi Guys,
Thanks for the many responses, I suspect I will be trying several, but both the EML and TJ sound interesting.
Despite starting the thread and choosing the title I was wondering whether anyone has tried the new JJ 2A3?
Comments on other types you have tried particularly in comparison to the TJ would be worthwhile..
I am currently using the Sovtek 2A3 in my new amplifier which is still waiting for its infusion of shizuki motor run ppio cathode bypass and power suply caps.
The highs are a little hashy which I associate with the electrolytic cathode bypass caps. or possibly the output tubes..
The driver stage is a direct coupled srpp using 7N7, eventually this will become a choke loaded mu-follower using exo-01 from MQ.
It's a really simple amplifier, and the performance except for the top octave is really surprisingly good with the Sovtek 2A3. Bass is very authoritative, mids well balanced, highs are not that great, but overall it is quick and detailed. I am sure a better output tube once the other changes are in place will be a worthwhile investment.
Thanks for the many responses, I suspect I will be trying several, but both the EML and TJ sound interesting.
Despite starting the thread and choosing the title I was wondering whether anyone has tried the new JJ 2A3?
Comments on other types you have tried particularly in comparison to the TJ would be worthwhile..
I am currently using the Sovtek 2A3 in my new amplifier which is still waiting for its infusion of shizuki motor run ppio cathode bypass and power suply caps.
The highs are a little hashy which I associate with the electrolytic cathode bypass caps. or possibly the output tubes..
The driver stage is a direct coupled srpp using 7N7, eventually this will become a choke loaded mu-follower using exo-01 from MQ.
It's a really simple amplifier, and the performance except for the top octave is really surprisingly good with the Sovtek 2A3. Bass is very authoritative, mids well balanced, highs are not that great, but overall it is quick and detailed. I am sure a better output tube once the other changes are in place will be a worthwhile investment.
Hi Cantskienuf:
are these the tubes you are talking about?
http://www.supertnt.com/default/product2a3-c.asp
are they electrically equivalent to regular 2a3 tubes? same heater voltage and recommended operating points? I'd be curious to try them in my paramours.
Kevin
are these the tubes you are talking about?
http://www.supertnt.com/default/product2a3-c.asp
are they electrically equivalent to regular 2a3 tubes? same heater voltage and recommended operating points? I'd be curious to try them in my paramours.
Kevin
are these the tubes you are talking about?
That's them. Same heater voltage. I haven't seen curves, but suspect from performance that op points are in line with Paramour design parameters. I spoke to Brian Cherry for a moment about them at RMAF this year and he seemed to favor them quite a bit also. I haven't found a U.S. source, so SuperTNT seems to be the only game for acquiring them.
hi kevin, it seems to me the Sovtek can take some beating. I had the wrong cathode resistor value once and i ran the Sovtek for a week at 60mA, 270Vp and still survives. I just find the sound at this operating point a bit "shouty". I saw some posts before in the Asylm I think where someone ran it at 300V
Hi Arnold,
I am running them at 62mA and 245V effective plate voltage which is near the max plate dissipation rating without any problems so far, linearity seems pretty good. The JJ, Sovtek and several others have higher dissipation ratings than NOS types did.
I need to (really) finish the amplifier, I should have the shizuki/asc motor run caps in a few days - these will replace the cathode bypass caps and the caps after the choke.
The EXO-01 from MQ are ordered and should be here in a month, I am hoping for a revelation..
Once all of the other changes are made I will be ready to really evaluate different output tubes..
I am running them at 62mA and 245V effective plate voltage which is near the max plate dissipation rating without any problems so far, linearity seems pretty good. The JJ, Sovtek and several others have higher dissipation ratings than NOS types did.
I need to (really) finish the amplifier, I should have the shizuki/asc motor run caps in a few days - these will replace the cathode bypass caps and the caps after the choke.
The EXO-01 from MQ are ordered and should be here in a month, I am hoping for a revelation..
Once all of the other changes are made I will be ready to really evaluate different output tubes..
Parafeed!
But Kevin, isn't that just 20mA or so?? The EXO-01, I mean. I use MagneQuest DS-025 on my 2A3 but would like to try parafeed someday.
I believe my DS-025 and RCA 2A3 deserves a better circuit, so I'm going ahead with that Pentode experiment I posted in the other 2A3 driver thread
But Kevin, isn't that just 20mA or so?? The EXO-01, I mean. I use MagneQuest DS-025 on my 2A3 but would like to try parafeed someday.
I believe my DS-025 and RCA 2A3 deserves a better circuit, so I'm going ahead with that Pentode experiment I posted in the other 2A3 driver thread
Hi Arnold,
The amplifier in question isn't going to be converted to a parafeed. Actually I am converting the dc coupled srpp driver stage into a choke loaded mu-follower, something I have advocated to others in the past, but didn't have the money to try - they liked it so I am encouraged to do the same now that I have the funds to comfortably indulge my curiosity.
This driver currently runs at 6.5 mA so the EXO-01 should work just fine. I bought a second pair so that if I like the results I can convert the driver in my 300B amplifier to the same topology. It is a very simple change that results in a totally different topology electrically by simply replacing the upper tube cathode resistor with the choke which in this case has a dcr of 1K, same as the cathode resistor it is replacing. (Why I choose it actually)
It provides an additional 3 - 4 dB of gain which I sorely need, linearity in simulations is markedly better than the SRPP connection at comparable output amplitudes. From listening experience with other people's amplifiers I have reason to believe it will sound better too, but we'll see. I'll be able to do a quick comparison to know for sure.
Also the ASC caps came this morning so they will go into the amplifier saturday morning. I am excited as this will allow me to eliminate all the electrolytics in the supply and signal path as well.
It's all good..
The amplifier in question isn't going to be converted to a parafeed. Actually I am converting the dc coupled srpp driver stage into a choke loaded mu-follower, something I have advocated to others in the past, but didn't have the money to try - they liked it so I am encouraged to do the same now that I have the funds to comfortably indulge my curiosity.
This driver currently runs at 6.5 mA so the EXO-01 should work just fine. I bought a second pair so that if I like the results I can convert the driver in my 300B amplifier to the same topology. It is a very simple change that results in a totally different topology electrically by simply replacing the upper tube cathode resistor with the choke which in this case has a dcr of 1K, same as the cathode resistor it is replacing. (Why I choose it actually)
It provides an additional 3 - 4 dB of gain which I sorely need, linearity in simulations is markedly better than the SRPP connection at comparable output amplitudes. From listening experience with other people's amplifiers I have reason to believe it will sound better too, but we'll see. I'll be able to do a quick comparison to know for sure.
Also the ASC caps came this morning so they will go into the amplifier saturday morning. I am excited as this will allow me to eliminate all the electrolytics in the supply and signal path as well.
It's all good..
Well you need to choose a choke that has sufficient RL at the lowest frequency of interest to be sure it will work properly. I am not certain that with the 6SL7's high rp that this will work that well, its late so I won't calculate the minimum inductance required for good low frequency response, but it will be way more than what I need with a 6SN7.. (like roughly 8 times higher) The EXO-01 is 285H and 1K and is a perfect drop in for my driver circuit.. You might want to convert to a 6SN7 if you plan to do this, gain will equal mu for this configuration and that ought to be enough if you use a line stage like the 12B4 discussed elsewhere on diyaudio..
Mu follower is not srpp, srpp is pushull, mu follower is not. Choke replaces the plate load resistor, cathode bias resistor, coupling cap and grid resistor found in the conventional mu follower, ac performance will be like mu follower, dc performance like srpp..
Mu follower is not srpp, srpp is pushull, mu follower is not. Choke replaces the plate load resistor, cathode bias resistor, coupling cap and grid resistor found in the conventional mu follower, ac performance will be like mu follower, dc performance like srpp..
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