not everyone , just ZM
🙂
send me an email , as soon you have anything else than DHL as option
Fedex, preferably
🙂
send me an email , as soon you have anything else than DHL as option
Fedex, preferably
A big thanks to ZD and everyone else who is making this possible. I just came to know of this and am quite keen to build this. Just trying to spec out a cost of the build. There are 52 pages in the thread and multiple threads that ZD pointed me to and I'm still going through them. So apologies in advance if this was discussed.
I'm hoping this won't be a complex build for someone with only soldering skills and the ability to handle a DMM since ZD offers an option with most parts soldered.
- ZD says "intended PSU is classic FW format - Donut with 2x18Vac secondaries , usually resulting in some 22V5dc rails (use CRC in filtering bank)" Could you point to a good PSU circuit for this?
- Any special specs for an "audio" grade mains toroid transformer?
- If one wanted a soft start (to avoid the loud pop through speaker) is there an add on circuit you recommend?
- Is any kind of speaker protection built-in? If not, any suggested circuit?
- Is any kind of thermal auto-off protection built-in? If not, any auggested circuit?
- Is it possible to have specs of the Cinemag transformer to be made locally? I know it will be impossible to beat a Cinemag but shipping to India + customs could be expensive (will check with Don's audio and Cinemag anyway).
- Confirming that the max power is 18Watts?
- Silly question maybe but would you say the amp is quiet/silent with no input?
- Is there a suggested enclosure? Again importing one will be expensive so if there was (ideally) a CAD drawing I could check with a local company.
Thanks for your time.
I'm hoping this won't be a complex build for someone with only soldering skills and the ability to handle a DMM since ZD offers an option with most parts soldered.
- ZD says "intended PSU is classic FW format - Donut with 2x18Vac secondaries , usually resulting in some 22V5dc rails (use CRC in filtering bank)" Could you point to a good PSU circuit for this?
- Any special specs for an "audio" grade mains toroid transformer?
- If one wanted a soft start (to avoid the loud pop through speaker) is there an add on circuit you recommend?
- Is any kind of speaker protection built-in? If not, any suggested circuit?
- Is any kind of thermal auto-off protection built-in? If not, any auggested circuit?
- Is it possible to have specs of the Cinemag transformer to be made locally? I know it will be impossible to beat a Cinemag but shipping to India + customs could be expensive (will check with Don's audio and Cinemag anyway).
- Confirming that the max power is 18Watts?
- Silly question maybe but would you say the amp is quiet/silent with no input?
- Is there a suggested enclosure? Again importing one will be expensive so if there was (ideally) a CAD drawing I could check with a local company.
Thanks for your time.
In my opinion, this should definitely NOT be your first amp project and you would be better off having built one of the other FW amps so you are familiar with the PSU build to eliminate any issue with that. Initial adjustment of this amp is probably the most challenging part as it is a very temperature sensitive circuit and patience is required. You have to adjust the front end separately from the output side and you have to measure and set your pots before you apply power. Additionally, if you have the original boards and find yourself with SITS with leaky gates, you will need to either learn to accept the drift or you will need to be ready for modification (or just do it from the beginning).
The original board is also designed for M25 (M2 variant) or SissySIT so values and populated parts will differ depending on which version you are building.
If you use the FW PSU, the CL60 thermistors will give you a degree of slow start but feel free to add any soft start and speaker protection (like the one offered by the diyAudio store) yourself. Just insert them into the appropriate locations.
I believe this was approximately 18W into 8ohms and higher into 4 ohms but since this is DIY, nobody will stop you from running higher voltages and/or more current. Just don't expect 50W ...
Thermal protection? No. There are probably circuits you could easily add as well or just get bigger heat sinks.
PSU recommendation - use the diyAudio store board. Well documented build guide as well - Universal Power Supply – diyAudio Store
For input autoformer (transformer), you can use cinemag cmoq-4 (L or H), edcor PC series (600:15K) or the Jensen from the F6 (something something 123-FLPCH), feel free to look up the specs of any of those.
My suggestion would be to recommend you build the M25 or even the store M2X first but if you are bold enough to attempt this and are willing to do the homework required to get yourself ready for this challenge, you will find yourself with an amazing amp. The M25 is also very highly praised and you don't have to deal with the SITs temperature nonsense but then again, you won't have a SIT amp either.
This amp runs very hot so find some heatsinks and then before asking if they are big enough, go find heatsinks that are twice as big.
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It's an exceptional amplifier in my opinion. Enjoy the build. 😀 As a fairly new builder when I built mine, I can offer one or two things that would have helped me. Pay very careful attention to all steps, but in particular, how to mount and wire the SIT to the heatsinks and boards respectively. Ensure proper insulators / thermal pad, and be sure to include the resistor. Follow the schematic and traces on the boards. I goofed it up (documented in the thread). Don't be like me
Zen Mod is always my final source for advice on his designs, but here's my $0.02.
The DIYAudio store has excellent boards, and there are quite a number of options out there. Not sure if you plan to order any other parts from there. Others living in India may have some advice for local options. I think ZM may have his own design. If so, you may consider getting a set from him to cut down on the number of shipments etc.
Shielded and/or potted is nice. Antek and Toroidy seem to be popular choices. Lots of discussion re: what makes a transformer "audio grade", but those two companies make quality products that seem to find their way into a lot of builds.
DIYAudio has a nice one available in the store, and a few other members have designed their own. However, FWIW, mine doesn't pop at all.
No. Again, DIYAudio store and/or many members have great options.
Not to my knowledge. I've never used one, so I can't offer advice on that.
Not sure. If you were to get specs from Cinemag (unlikely) then you'd have to get one custom wound. If that's cheaper than shipping and duties etc. then you could try it, but it's unlikely. Edcor is also a known tested brand (I used Edcor in mine) along with Jensen (I believe). Perhaps those may be easier to source.
Depends on the load. ZM, has details.
Mine is.
There are tons of options for enclosures. Zen Mod can better assist on how much heatsink is recommended. From there, it's just a box. If you're going to use a local fabricator - a rough sketch should do for them. They don't need CAD most likely.
Enjoy the build and the music!
Dang... I could have saved a ton of typing by just saying +1 to Twitchie. That'll teach me to update my screen.
This chassis/heatsink dimension should be ok:
Nobsound Large sized Aluminum Chassis Class A Power Amplifier Enclosure DIY Cabinet Case|Amplifier| - AliExpress
I have built one into this chassis but I don't run any speaker or thermal protection in any of my amps either... if you are a normal person or even a bit cautious, you should probably not do as I do
my case
Amp is silent with no input (yes)
Nobsound Large sized Aluminum Chassis Class A Power Amplifier Enclosure DIY Cabinet Case|Amplifier| - AliExpress
I have built one into this chassis but I don't run any speaker or thermal protection in any of my amps either... if you are a normal person or even a bit cautious, you should probably not do as I do
my case
Amp is silent with no input (yes)
Dang... I could have saved a ton of typing by just saying +1 to Twitchie. That'll teach me to update my screen.
+1 to what AIMH said 😀
You'll need at least 2 DMMs, better off with 3 or even 4 and no, most of the parts are not soldered, only the tiny surface mount jfets and hall chips are pre-soldered. You still have to install all the through-hole parts.
Considering the cost for Tokin SITs, this will not be a cheap build compared to something like the F5 or Aleph-J.
You don't mention what you've successfully built (or unsuccessfully but attempted is almost as good). In my opinion, the F5 is the amp that should be easiest to build with lowest part count and (reasonably) available parts and if you burn one up while attempting it, it's not a big loss.
I just want to second what my friends twitchie and IAIMH have written.
I would just add that personally I would just order one of the supported input
transformers. The transformer is PCB mounted and trying to
get a custom one made, and matching the existing footprints seems like
a risky proposition to me.
The Jensen is available on ebay. Try the seller cable solutions. They have different shipping options available
I would just add that personally I would just order one of the supported input
transformers. The transformer is PCB mounted and trying to
get a custom one made, and matching the existing footprints seems like
a risky proposition to me.
The Jensen is available on ebay. Try the seller cable solutions. They have different shipping options available
I have built the M2, F5T and Sissy SIT. The most challenging one is the latter and thankfully, I had some help. It is also the most musical one. I like the airy and soundstaging.
Build it, you won’t regret it.
Build it, you won’t regret it.
naah
it's really extra simple, just 2,5 parts singing - input xformer and SIT & Mosfet together (fighting each other)
🙂
it's really extra simple, just 2,5 parts singing - input xformer and SIT & Mosfet together (fighting each other)
🙂
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Just my two cents as a not so experienced builder:
I was lucky to have a friend with a lot more transistor amp building experience on board, when I decided to start my first transistor amp project. This was a M2 clone project. For me the best placement/mounting of transformers, power supply and soft start boards, etc. was the tricky part and Alex, my friend, was of great support here. The soldering and the biasing of the M2 clone went fine for me. Patience is needed though!😀
With the SissySIT I know that the biasing of the amp will be more challenging and for me also the drilling and thread cutting for the correct mounting of the SIT will be a challenge. But as I have lived with a SissySIT for some months, it is a must to make this project happen. And in my case it will be easier as amp case and ps section of my M2 can be fully used. On top of that, ZenMods instructions and info in the SissySIT building tricks thread are very helpful and clear.
So here is, why the SissySIT is a must in my opinion:
In early 2020 Alex transformed his M2 clone (a double mono psu version built into the Modus Shop Dissipante 5U chassis with 400mm depth) into a SissySIT amp thanks to ZenMod’s great boards. He used a set of THF51S SITs from pras1701. Then in March, I got lucky as Alex lent me his amp for a listen a week before the Covid-19 lockdown in Austria and the amp has stayed with me since then. Good to have a generous friend… 🙂.
I really enjoy my M2 clone but what I hear from the SissySIT connected to my 3-way Haigner horns is in another league. The SissySIT is faster, livelier with superb timing and shines in the bass department with a lot of shading. I never heard such multifaceted bass from a transistor amp. The midrange and treble clarity is superb. This amp has a special magic in presenting music from CD or vinyl. To my ears, it is a super music communicator…😀
Congrats and thanks to ZenMod - of course also to Mr. Pass - for making such a great SIT-implementation possible!
Clearly, it is now time for me to get my SissySIT-project going and transform my M2 clone into a SIT-based music machine. The boards and parts are all here and waiting… I’ll keep you posted.
I was lucky to have a friend with a lot more transistor amp building experience on board, when I decided to start my first transistor amp project. This was a M2 clone project. For me the best placement/mounting of transformers, power supply and soft start boards, etc. was the tricky part and Alex, my friend, was of great support here. The soldering and the biasing of the M2 clone went fine for me. Patience is needed though!😀
With the SissySIT I know that the biasing of the amp will be more challenging and for me also the drilling and thread cutting for the correct mounting of the SIT will be a challenge. But as I have lived with a SissySIT for some months, it is a must to make this project happen. And in my case it will be easier as amp case and ps section of my M2 can be fully used. On top of that, ZenMods instructions and info in the SissySIT building tricks thread are very helpful and clear.
So here is, why the SissySIT is a must in my opinion:
In early 2020 Alex transformed his M2 clone (a double mono psu version built into the Modus Shop Dissipante 5U chassis with 400mm depth) into a SissySIT amp thanks to ZenMod’s great boards. He used a set of THF51S SITs from pras1701. Then in March, I got lucky as Alex lent me his amp for a listen a week before the Covid-19 lockdown in Austria and the amp has stayed with me since then. Good to have a generous friend… 🙂.
I really enjoy my M2 clone but what I hear from the SissySIT connected to my 3-way Haigner horns is in another league. The SissySIT is faster, livelier with superb timing and shines in the bass department with a lot of shading. I never heard such multifaceted bass from a transistor amp. The midrange and treble clarity is superb. This amp has a special magic in presenting music from CD or vinyl. To my ears, it is a super music communicator…😀
Congrats and thanks to ZenMod - of course also to Mr. Pass - for making such a great SIT-implementation possible!
Clearly, it is now time for me to get my SissySIT-project going and transform my M2 clone into a SIT-based music machine. The boards and parts are all here and waiting… I’ll keep you posted.
One correction to my post #993: The Tokin THF-51S were bought from pras1170 of course. (I can't find / see the "edit" my post function)
Thank you for all the warnings and encouragement. I am cautious about progressing but if it happens it will be under your valuable guidance. I'll also see if I can find someone with experience to assist.
@ItsAllInMyHead, thanks. I'll look at the store for those circuits. Will check with ZM on his PSU. Yes, better to get all parts at one window.
@twitchie, I've built the Pass B1, HQMCPS phono and some other stuff. I've also been zapped couple of times by the 230 mains if that counts as experience 🙂 If 4 DMMs are really required that could be an issue.
@Dennis, Thanks for the critical info that the transformer fits on the PCB.
Just out of curiosity, does the CRC PSU work just as well?
BTW, saw ZM's build on his blog and that is one beautiful build!
Probably come back with more questions after reading a bit more.
@ItsAllInMyHead, thanks. I'll look at the store for those circuits. Will check with ZM on his PSU. Yes, better to get all parts at one window.
@twitchie, I've built the Pass B1, HQMCPS phono and some other stuff. I've also been zapped couple of times by the 230 mains if that counts as experience 🙂 If 4 DMMs are really required that could be an issue.
@Dennis, Thanks for the critical info that the transformer fits on the PCB.
Just out of curiosity, does the CRC PSU work just as well?
BTW, saw ZM's build on his blog and that is one beautiful build!
Probably come back with more questions after reading a bit more.
To save a bit of clicking around on the store site - here are the specific things I mentioned.
Universal Power Supply – diyAudio Store
Soft Start & Speaker Turn-On Delay / DC Protector Combo – diyAudio Store
As for other sources, I've heard great things about the Smooth Like Butter PSU, and also XRKs implemenation for soft start etc. Here is a thread on the PSU. Within his signature, you can find his online shop. There are tons of other sources others could recommend from their personal use / knowledge, but the store shop and his are the only two I know personally.
The SLB (Smooth Like Butter) Active Rect/CRC/Cap Mx Class A Power Supply GB
One other addition since it's impossible to know anyone's level of experience or preferences. Personally, I am terrible at machine work. So, I always recommend to have all holes tapped to their precise locations by an experienced shop. I've tried it myself with some success. However, if you're going to use a shop for your case - then you may as well have them tap a few holes for you. The Modushop cases in the store are used quite often with success. I like them, and ZMs boards are set up for the Universal Mounting System, and the spacing for the SITs is simple.
Cheers.
Universal Power Supply – diyAudio Store
Soft Start & Speaker Turn-On Delay / DC Protector Combo – diyAudio Store
As for other sources, I've heard great things about the Smooth Like Butter PSU, and also XRKs implemenation for soft start etc. Here is a thread on the PSU. Within his signature, you can find his online shop. There are tons of other sources others could recommend from their personal use / knowledge, but the store shop and his are the only two I know personally.
The SLB (Smooth Like Butter) Active Rect/CRC/Cap Mx Class A Power Supply GB
One other addition since it's impossible to know anyone's level of experience or preferences. Personally, I am terrible at machine work. So, I always recommend to have all holes tapped to their precise locations by an experienced shop. I've tried it myself with some success. However, if you're going to use a shop for your case - then you may as well have them tap a few holes for you. The Modushop cases in the store are used quite often with success. I like them, and ZMs boards are set up for the Universal Mounting System, and the spacing for the SITs is simple.
Cheers.
Are the 2sk182ES he is selling on ebay the same as the thf-51s? He does not show any THF-51S for sale.
oreo382, I reached out to pras1170 via PM and email to ask about and purchase a pair of THF's. You're right, he doesn't have them listed on eBay right now.
Tomo has some THF-51S listed:
A pair(2pcs) THF-51S (2SK77,2SK180,2SK182) TOKIN V-FET NOS Original JAPAN MADE | eBay
A pair(2pcs) THF-51S (2SK77,2SK180,2SK182) TOKIN V-FET NOS Original JAPAN MADE | eBay
contact Pras here via PM
until now , we all were good and happy - she was happy with us and we were happy with her
exactly as expected from proper and decent trade
between her and watanabetomoaki, you still got opportunity to snatch some
but, blame Pa ( as always and as for everything) , for shortage in quantity
ZM is little Kitty, taking both in account all SITs I have , and got how many people to buy them ..... Pa is Le Grande Tiger
until now , we all were good and happy - she was happy with us and we were happy with her
exactly as expected from proper and decent trade
between her and watanabetomoaki, you still got opportunity to snatch some
but, blame Pa ( as always and as for everything) , for shortage in quantity
ZM is little Kitty, taking both in account all SITs I have , and got how many people to buy them ..... Pa is Le Grande Tiger