Single Ended Tokin SIT THF-51S Common Drain Mu Follower Amplifier, 45W?

[finwbu]

Tokin SIT testing facility: Only Mitsubishi , Toshiba and NEC was using them. Kone never

 

[sp33ls]

I will take pride knowing the sits I own were removed from elevator service and no one died.

Bill

lol. I'm guessing most are pulled due to EOL status and swapped out for something different altogether?

 

[vdi_nenna]

I'll bet the elevator music sounded fantastic!

 

[Ben Mah]

Listening to 2SK180 elevator music right now but soon it will be cold enough for THF-51S music.

 

[codyt]

I’ve just accepted that a thin layer of sweat is part of the ‘charm’ of a 50W single-ended amp

 

[Ben Mah]

Why sweat it when it is possible to have a SIT amp for every season?

I may build a summer SIT amp, possibly a choke loaded 2SJ28 follower.

 

[Zen Mod]

I've built small one, for all seasons

 

[codyt]

This little 50w amp of mine is worth sweating for year round

I’ve been slowly collecting parts for complimentary CD Sony amp from a few years ago. I imagine it would be a good summer amp. Also have sissy and another (lazy) follower to tackle at some point.

 

[Dennis Hui]

I imagine it would be a good summer amp.

The dissipation is no more than a standard FW amp so it should be
a fine summer amp. I think you'll like it.

 

[codyt]

I think you’re right, and I’m looking forward to building one. Luckily I’ve had some help finding the harder to get parts for the project

 

[Ben Mah]

I have the diyAudio push-pull VFET amp and it is a nice amplifier, but I prefer single ended followers.

However that amplifier did start me down the path of solid state amplifiers.

 

[codyt]

I agree that there is some serious magic involved in the single ended CD amp, at least in the example I’ve heard (10W Sony). I’m excited to eventually try it out on a larger scale, just as you have done here.

 

[MEGA_amp]

custom chokes

If anyone is interested...I had custom chokes made from these guys, specifically for Ben's 'little' follower amp. 200mH @ 10A, 57Lbs each certainly wasn't cheap. Hopefully it's big enough I'll post a few pics when it arrives.

Electronic Craftsmen | Custom Transformers, Custom Inductors, Electronic Craftsmen

 

[Ben Mah]

That's not for a "little" amp. It's got to be "MEGA".

 

[ichiban]

Yes! 'MEGA' in 2022 !!!

 

[BRN]

I’m following this thread with great interest. I came from the SET camp when I started my DIY journey. I have now come to greatly appreciate the sand amp world and every build is seems to be a step forward in sound quality for me. Building the F2J, which is my first SE SS amp, has been an eye opener for me in what I like. Thank you codyt and NP for making them available. I want to build another SE amp, but something with a little more power so I have more speaker options.

I have a pair of matches THF-51s sitting on the shelf waiting and reading this thread has perked my interest in the CD MU Follower. Thank’s Ben for posting your build. I’m not sure I’m up to the task of building my own boards. I my try one of the circuitboard programs and see if I can design them.

Codyt are you using ZM’s boards for your build?

 

[codyt]

Glad you’re liking F2J! Regarding my mu CS amp, yes, I used ZM’s Singing Bush boards, and they are highly recommended. If you’re more interested in the CD follower topology, you should see ZM offering a version of this called the ‘Lazy’ Singing Bush sometime in the future.

All that said, either of those topologies could be fairly straightforward builds on perf board, as Ben has shown.

 

[BRN]

Codyt,

I think that I will try laying out some boards. I have rhthatcher's PS boards. I would have to reverse them for this configuration though.

I have one project that I'm working on before get to this, so I think I will call my build the "Slow Common Drain Mu Follower Amplifier."

 

[codyt]

BRN, that’ll be a fun project to tackle. Over the past few months I’ve slowly been learning Kicad and making little preamp boards. It’s a lot of fun and very rewarding.

 

[grataku]

Cody,
I am happy that you convinced ZM to work on the Lazy version. I am waiting for him to complete testing and I'll be getting both.

What kind of gainstage is suitable for this amp?