Hi George.
I ordered a pair of the PQ5EV5 from Suburban Electronics, as per your link. Thanks for the link!
It would be helpful if you could provide Tubelab approved alternates to no longer available solid state components on your site. I ordered an SSE board and a SE board last year, but put off the build for awhile, and some of the components are now very difficult to find. Also, components can fail. Either way, having a readily accessible and George approved alternate would be a helpful addition to your already very comprehensive site. I know I would appreciate it, and I’m sure others would as well.
I ordered a pair of the PQ5EV5 from Suburban Electronics, as per your link. Thanks for the link!
It would be helpful if you could provide Tubelab approved alternates to no longer available solid state components on your site. I ordered an SSE board and a SE board last year, but put off the build for awhile, and some of the components are now very difficult to find. Also, components can fail. Either way, having a readily accessible and George approved alternate would be a helpful addition to your already very comprehensive site. I know I would appreciate it, and I’m sure others would as well.
Driver tubes not changing. It was requested more than once I think, but a suitable substitute wasn't found (based on this thread).
PQ5EV5 from Suburban Electronics
Hi George.
The pair of PQ5EV5 arrived from Suburban Electronics today. Delivery was quick, and they appear to be the genuine article. Once again, a list of Tubelab approved SS components to replace ones that are end of life/no longer available would be a much appreciated addition to your site. Thanks again for the link to the PQ5EV5s.
Hi George.
The pair of PQ5EV5 arrived from Suburban Electronics today. Delivery was quick, and they appear to be the genuine article. Once again, a list of Tubelab approved SS components to replace ones that are end of life/no longer available would be a much appreciated addition to your site. Thanks again for the link to the PQ5EV5s.
Attachments
I will make such a list as I begin building up some more TSE-II boards. Unfortunately there was a long period of time when I didn't build anything. I still have a couple of complete TSE boards from the initial build in 2006 that I never used, so I haven't built any TSE boards in a long time. I keep them around for testing alternative parts when necessary.
Not much needs changing except for the mosfets. I have been using plain old UF4007's for the negative voltage supply. The new TSE -II with UF4007's in it is so quiet that I connected my headphones directly up to the speaker outputs on a 45 based TSE-II. Dead quiet except for a 'TWANG" when you whack one of the 5842's with a pencil.
Not much needs changing except for the mosfets. I have been using plain old UF4007's for the negative voltage supply. The new TSE -II with UF4007's in it is so quiet that I connected my headphones directly up to the speaker outputs on a 45 based TSE-II. Dead quiet except for a 'TWANG" when you whack one of the 5842's with a pencil.
Is there any reason the TSE-II would be quieter than the original?
I thought the designs were pretty similar.
Randy
The designs are similar, but I snuck a couple of minor improvements in. There are now 3 electrolytics in parallel for C1 in the filament supply. This kills all the ripple when a pair of hungry 2A3's are sucking 5 amps out of a 5 amp chip. The board layout is all new, and there is now a star grounding system where the high current filament ground, positive and negative supply ground, and signal ground all meet in exactly one point, the negative end of the big fat cap across B+.
What is the final dimensions for the new board? I read you were expanding it but could find the final dimensions.
Also, are the connectors in a similar place than for the original?
I have bought all the ancillary iron and other components and am thinking of arranging them on a prototyping wooden board I relation to the new PCB.
Thanks, Patrick
The audio signal path is exactly the same. I added a 1K stopper resistor to the gates of the mosfets to cope with today's ultra fast fets. I also added a zener - resistor regulator to reduce the drain voltage on the fets to 150 volts for cooler running, but neither change should impact the sound.....the TSE is a good sounding amp, why mess it up. If you like your TSE, there is no need to make a new one, except of course for the bigger footprint.
The old Sharp regulator was the best available 15 years ago, and that is still true. The new Microchip part is a few millivolts worse in the dropout region, so I added two more caps in parallel with C1. These could be added to an existing TSE off board (with short fairly heavy wires) if needed, but that shouldn't be needed unless you are running 2A3's with a marginal power transformer.
I have noticed that the new test board is dead quiet with headphones wired directly to the speaker terminals. I suspect that has more to do with my new lab environment compared to the lab in Florida, than the board itself, but I'll do some direct A/B comparisons once the real boards come in.
The new board is 8.5 inches by 5.5 inches.
The original board did not use the screw type connectors, it just had solder pads spaced at odd intervals. The new board uses the same connectors found on all my newer boards although direct wiring is still possible if preferred. All the connections are along the same edges of the board as on the original. A connection for a choke have been added like what is found on the SSE.
Hi George,
I have been lurking (and enjoying) Tubelab threads for a long time, but have never posted before. With the TSE-II hopefully available soon for purchase, I plan to build one ASAP. In looking at your prototype I noticed it accommodates a 4-pin power tubes only.
The reason for my post now is a request: Is it possible to provide the option to use octal power tubes like 6B4, or xLW6? I have a dozen or so 6B4 in storage as well as 26LW6s, so the option to use them is of great interest to me.
You wrote about using xLW6 tubes also, so I wondered if you had intended all along to provide for octals on or off the PCB. Are you are familiar with Pete Millett’s 50 watt mono block PCB that has holes where the power tube sockets should go so that the builder can hookup any of the compatible sweep tubes. Perhaps the TSE-II power tube sockets could be off the PCB if it is problematic to have both types of sockets on board.
Best wishes with completing the development work on the new PCB and getting them in you on-line store.
I have been lurking (and enjoying) Tubelab threads for a long time, but have never posted before. With the TSE-II hopefully available soon for purchase, I plan to build one ASAP. In looking at your prototype I noticed it accommodates a 4-pin power tubes only.
The reason for my post now is a request: Is it possible to provide the option to use octal power tubes like 6B4, or xLW6? I have a dozen or so 6B4 in storage as well as 26LW6s, so the option to use them is of great interest to me.
You wrote about using xLW6 tubes also, so I wondered if you had intended all along to provide for octals on or off the PCB. Are you are familiar with Pete Millett’s 50 watt mono block PCB that has holes where the power tube sockets should go so that the builder can hookup any of the compatible sweep tubes. Perhaps the TSE-II power tube sockets could be off the PCB if it is problematic to have both types of sockets on board.
Best wishes with completing the development work on the new PCB and getting them in you on-line store.
