vzaichenko, you wrote:
"C102/C105 will see almost the full rails voltage, so "no go" for 35V rating. It has to be 100V".
Kan I use 100uF/100V that I have instead of 22uF?
Eivind S
Yes, you can use 100uF/100V there, assuming two things:
1) You can fit them on the board (they are most likely bigger size);
2) Your front-end rails will raise slower on power-on, so DC offset settling will most likely take longer for the whole amplifier (possibly, speaker delay will have to be increased in the protection circuit).
Cheers,
Valery
Time to get going
Started testing my 3 pair OPS with Spooky yesterday. Thanks to all the hard work put in by Pete, Still4given, Thimios, Valery and all the other stalwarts, the test passed with flying colours 🙂 Started off with a supply of +/-33V and then progressed to +/- 42V (final target is +/- 65V). Was able to set the bias smoothly at 68 ma. With Q104 mounted under the board onto the main heatsink, the amp is very stable. Have been playing some music through it and sure sounds great. Can't wait to complete the other channel now!!!!
Started testing my 3 pair OPS with Spooky yesterday. Thanks to all the hard work put in by Pete, Still4given, Thimios, Valery and all the other stalwarts, the test passed with flying colours 🙂 Started off with a supply of +/-33V and then progressed to +/- 42V (final target is +/- 65V). Was able to set the bias smoothly at 68 ma. With Q104 mounted under the board onto the main heatsink, the amp is very stable. Have been playing some music through it and sure sounds great. Can't wait to complete the other channel now!!!!
Attachments
Started testing my 3 pair OPS with Spooky yesterday. Thanks to all the hard work put in by Pete, Still4given, Thimios, Valery and all the other stalwarts, the test passed with flying colours 🙂 Started off with a supply of +/-33V and then progressed to +/- 42V (final target is +/- 65V). Was able to set the bias smoothly at 68 ma. With Q104 mounted under the board onto the main heatsink, the amp is very stable. Have been playing some music through it and sure sounds great. Can't wait to complete the other channel now!!!!
Very, very nice! looking forward to the full review.
Gooday, I have a problem finding through hole MURS120 fast recovery diodes for the FET output version. Is there another option available with leads ?
Thanks
Thanks
Hi Vrystaat.
Here a mouser link.
http://www.mouser.de/Search/Refine.aspx?Keyword=MUR120
Only without -S- you came back to through hole.
Here a mouser link.
http://www.mouser.de/Search/Refine.aspx?Keyword=MUR120
Only without -S- you came back to through hole.
Hello all...
Slowly putting together a spooky/ arc welder (5p of njw0281/njw0302) and they will be mono blocs using 50-50 625va transformers....
Now the question 🙂 can I re-use my heatsinks from my 4u case? They are 300x165x40 https://www.modushop.biz/site/index.php?route=product/product&path=71_149_161&product_id=345
Just trying to recycle🙂
Thanks....
Tony
Slowly putting together a spooky/ arc welder (5p of njw0281/njw0302) and they will be mono blocs using 50-50 625va transformers....
Now the question 🙂 can I re-use my heatsinks from my 4u case? They are 300x165x40 https://www.modushop.biz/site/index.php?route=product/product&path=71_149_161&product_id=345
Just trying to recycle🙂
Thanks....
Tony
Hello all...
Slowly putting together a spooky/ arc welder (5p of njw0281/njw0302) and they will be mono blocs using 50-50 625va transformers....
Now the question 🙂 can I re-use my heatsinks from my 4u case? They are 300x165x40 https://www.modushop.biz/site/index.php?route=product/product&path=71_149_161&product_id=345
Just trying to recycle🙂
Thanks....
Tony
The heatsink size is fine. You'll need to do some planning to fit all your parts into the case though. The output board is almost the full length of the case.
Another Slewmonster lives!
My Slewmaster build has finally been completed. Only three years in the making...
This is the first build of this scale I have built. While my spaghetti wiring is a little messy, I have absolutely no problems with noise or hum.
My initial listening impressions so far is that it sounds similar to the Harman Kardon pa2400 I have recently acquired. While my Slewmaster with Spooky front end clearly beats it in the extreme high and low frequencies.
Here are some quick photos of my build and the shop space I have been working from.
My Slewmaster build has finally been completed. Only three years in the making...
This is the first build of this scale I have built. While my spaghetti wiring is a little messy, I have absolutely no problems with noise or hum.
My initial listening impressions so far is that it sounds similar to the Harman Kardon pa2400 I have recently acquired. While my Slewmaster with Spooky front end clearly beats it in the extreme high and low frequencies.
Here are some quick photos of my build and the shop space I have been working from.
Attachments
Excellent!My Slewmaster build has finally been completed. Only three years in the making...
This is the first build of this scale I have built. While my spaghetti wiring is a little messy, I have absolutely no problems with noise or hum.
My initial listening impressions so far is that it sounds similar to the Harman Kardon pa2400 I have recently acquired. While my Slewmaster with Spooky front end clearly beats it in the extreme high and low frequencies.
Here are some quick photos of my build and the shop space I have been working from.



An absolutely protected SlewMaster!
What size is this Modu enclosure?
Mine is far from finished.🙁
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Excellent!
An absolutely protected SlewMaster!
What size is this Modu enclosure?
Mine is far from finished.🙁
I used the 5U 400mm deep case. A 4U height case would be more than tall enough, but I would recommend a 400mm deep case, so everything isn't crammed too close together. I also recommend the optional base plate to avoid all that weight being attached to the relatively flimsy in comparison bottom cover. What I assumed early on was too big, ended up being barely big enough.
The relay board is the excellent 21st century speaker protection system V5.1. You can find more information by searching for "21 st century speaker protection" in this forum.
Thanks for informations.I used the 5U 400mm deep case. A 4U height case would be more than tall enough, but I would recommend a 400mm deep case, so everything isn't crammed too close together. I also recommend the optional base plate to avoid all that weight being attached to the relatively flimsy in comparison bottom cover. What I assumed early on was too big, ended up being barely big enough.
The relay board is the excellent 21st century speaker protection system V5.1. You can find more information by searching for "21 st century speaker protection" in this forum.
I know all about 21st century speaker protection system.
Jeff and Valery has done a very good job here.😎
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My Slewmaster build has finally been completed. Only three years in the making...
This is the first build of this scale I have built. While my spaghetti wiring is a little messy, I have absolutely no problems with noise or hum.
My initial listening impressions so far is that it sounds similar to the Harman Kardon pa2400 I have recently acquired. While my Slewmaster with Spooky front end clearly beats it in the extreme high and low frequencies.
Here are some quick photos of my build and the shop space I have been working from.
Great looking build!
I see a familiar control board with I2C flat cables 😉
Perfect 👌
akimmet: Nice build and great choice of protection system. 🙂
What rail voltage are you running?
What rail voltage are you running?
I am only running 59V rails, but I wanted an amplifier that could handle 4 Ohm loads.
I using MJL4281/MJL4302 for the outputs, and 2SC5242/2SA1962 for the drivers.
I using MJL4281/MJL4302 for the outputs, and 2SC5242/2SA1962 for the drivers.
Time to get going
Final testing done today at +/- 63VDC (both channels going). The performance is simply mind blowing
The bass response is amazing. Played a lot of ZZ Top, Pearl Jam, Dire Straits, Eagles etc. from my phone. With the EQ on the phone set to "FLAT", the notes were crystal clear and deep punchy bass. Once again, a million thanks to all the stalwarts who did all the experiments and testing 
Hari
Final testing done today at +/- 63VDC (both channels going). The performance is simply mind blowing


Hari
Attachments
It's good to see another up and running, now comes final assembly. It will be interesting to see your amp when fully assembled.
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