SA2021 - NCH (New Class H) dual mono tower coming soon ...
270W@8R , 540W@4R stable to 2R ...
Cabling nearly finished...
BR, Toni
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Working out of the box. Awesome THD+N, SNR values.
Sound is ultra high end transparent - gainwire ...
Absolutely no hum and only a very small white noise level hear able with ears directly at the scanspeak beryllium tweeters ... wow
My new "Ultra high end reference" Amplifier with built in "green functions" ... Thanks goes to the help of the diyaudio community and especially Dave Zan for his really great contribution to make this project possible! https://diyaudio.com/forums/posts/7423157
Have fun, Toni
Sound is ultra high end transparent - gainwire ...
Absolutely no hum and only a very small white noise level hear able with ears directly at the scanspeak beryllium tweeters ... wow
My new "Ultra high end reference" Amplifier with built in "green functions" ... Thanks goes to the help of the diyaudio community and especially Dave Zan for his really great contribution to make this project possible! https://diyaudio.com/forums/posts/7423157
Have fun, Toni
Attachments
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After more as an hour playing sound the temperatures are:
left heatsink: 35 °C
right heatsink: 36 °C
case bottom - big power supplies: 25 °C
case middle- small power supplies: 31 °C
mcu: 31 °C
room: 22 °C
after another hour : 36, 37, 26, 33, 32, room 22
If you would like to see more detail photos from the inner, let me know with many "likes" here!
left heatsink: 35 °C
right heatsink: 36 °C
case bottom - big power supplies: 25 °C
case middle- small power supplies: 31 °C
mcu: 31 °C
room: 22 °C
after another hour : 36, 37, 26, 33, 32, room 22
If you would like to see more detail photos from the inner, let me know with many "likes" here!
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Idle/first watt power dissipation for this power horse is total with all housekeeping about 84W for 2 channels. Class A current is 500mA per channel. Above 15W/30W (8R/4R) the upper high voltage power supply will be used. The THD glitch in this region is very low (total THD+N 0.003% up to 0.005% and decreasing above again). Peak output power with about 350W/8R or 700W/4R should be possible... of course with THD levels ~ 0.00xx percent. (THD+N is meant from 20Hz-20kHz)
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Some more details to SA2021-NCH
Front, back, top and sides removed or unscrewed. At each bottom of the heatsinks is a 3D printed vent mounted. To get the beast totally hum free the cabling is special. Input star ground connected to input and main star ground. The RCA input signals use a shielded cable where the shield is connected only at the input terminals star ground. A thick grounding cable connects the amp input GND to RCA input. The speaker ground is connected at the backplane star ground. Chassis is decoupled from earth with a dual bridge diode ground breaker. The AC input is filtered using a Schurter (DD12-series) device incl. power switch and dual fuses. Internally the AC has a high power DC filter for the toroid primaries.
The alu bar viewable here is only for maintenance when the amp/heatsink modules are dismounted.
Have fun,
Toni
Front, back, top and sides removed or unscrewed. At each bottom of the heatsinks is a 3D printed vent mounted. To get the beast totally hum free the cabling is special. Input star ground connected to input and main star ground. The RCA input signals use a shielded cable where the shield is connected only at the input terminals star ground. A thick grounding cable connects the amp input GND to RCA input. The speaker ground is connected at the backplane star ground. Chassis is decoupled from earth with a dual bridge diode ground breaker. The AC input is filtered using a Schurter (DD12-series) device incl. power switch and dual fuses. Internally the AC has a high power DC filter for the toroid primaries.
The alu bar viewable here is only for maintenance when the amp/heatsink modules are dismounted.
Have fun,
Toni
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Back/top panel Views. Front panel needs more work (currently only a black anodized aluminium part). Home brew LED VU meter and power switch need to be added ...
Coming soon...
Very heavy part - not far below 50 kg weight - I'm not able to carry this beast ...
Have fun,
Toni
Coming soon...
Very heavy part - not far below 50 kg weight - I'm not able to carry this beast ...
Have fun,
Toni
Attachments
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@astx, why not building as monoblocks ? I'm guessing that the toroids are from Toroidy, they are located far away from signal, is there any reason choosing the Supreme edition over the Audiophile (huge difference in money between them) one other than 'it's a 'money-no-object amplifier' ?
Anyway, great job 👍
Anyway, great job 👍
Thx for the kind words! SA2021-NCH is a dual mono block in one case. Channel separation is not measureable. Noise/hum is lower as my equipment can measure. (Levear Vp7723D, QA403). Toroidy: the price difference selecting the supreme edition vs normal toroids is low - the look (and also the shielding) is outstanding. The transformers are made especially for SA2021-NCH with 5 different secondary voltages (no middle tap!). 2x55V (6.4A), 2X16V (3A) and a helper voltage 12V (1.7A). (BTW: The manufacturing of the top aluminium cover was more expensive as the 2 transformers).
This diy amp is a bargain in comparison what the high end audio industry want to have $/€.
At the end of the day this counts: It is DIY from schematic, pcb development to case - Have fun, Toni
This diy amp is a bargain in comparison what the high end audio industry want to have $/€.
At the end of the day this counts: It is DIY from schematic, pcb development to case - Have fun, Toni
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Gosh, forgot about that. Someone that haven't got in the 'pit of hell' of putting the amp into chassis might not even notice this, he'd look at your top plate and go: 'uh, nice thingy, 10 bucks'. I have a similar (though AB) amp to put into chassis and I have different opinion every day (to mono or not to mono)The manufacturing of the top aluminium cover was more expensive as the 2 transformers
Toroidy is very reasonably priced but still a 400VA costs 90 eur. Audio Grade and 170 Supreme Grade and if positioning the transformer might give you a reason to save money you might compromise willingly. Is there any difference in construction aside the steel cover ? But that belongs to the Parts forum, sooooo... again great job
A closer look even reveals more unique features like the unique honey-hole cover (is there a glass besides it ?) at the side and the capacitors top caps.
ToniSome more details to SA2021-NCH
Front, back, top and sides removed or unscrewed. At each bottom of the heatsinks is a 3D printed vent mounted. To get the beast totally hum free the cabling is special. Input star ground connected to input and main star ground. The RCA input signals use a shielded cable where the shield is connected only at the input terminals star ground. A thick grounding cable connects the amp input GND to RCA input. The speaker ground is connected at the backplane star ground. Chassis is decoupled from earth with a dual bridge diode ground breaker. The AC input is filtered using a Schurter (DD12-series) device incl. power switch and dual fuses. Internally the AC has a high power DC filter for the toroid primaries.
The alu bar viewable here is only for maintenance when the amp/heatsink modules are dismounted.
Have fun,
Toni
Some impressive work !!
Just wondering about PSU, have You considered to use active PSU ? The easiest way to lower output impedance of PSU is to add NFB, It can be done very simple way. Some example bellow. A few components and we have, smaller, better filtrated, lower output impedance PSU.
Great work !!
Attachments
Dear Savvas,Is there any difference in construction aside the steel cover ? But that belongs to the Parts forum, sooooo... again great job
A closer look even reveals more unique features like the unique honey-hole cover (is there a glass besides it ?) at the side and the capacitors top caps.
regarding "toroidy" steel cover: it looks so good - it was the main reason to buy this customized variant, of course you could use any other high quality transformer too ...
BTW: you are the first who recognized the small details what makes this amp so unique. 3D printing is a new amazing tool to get closer to a professional amplifier design. It allows you to design parts for isolation et al.
E.g. 230V capacitor top, cable routing safety parts, raster plate at heatsink bottom ...
All (EMI required) alu honeycomb structures are covered with a 3mm acrylic sheet (70% light throughput; better looking would be a 30% only throughput acrylic panel - need to change it somedays).
This extras are designed only to view a bit of the electronics inside.
Have fun, Toni
The SA2021-NCH story continues ...Back/top panel Views. Front panel needs more work (currently only a black anodized aluminium part). Home brew LED VU meter and power switch need to be added ...
Coming soon...
Very heavy part - not far below 50 kg weight - I'm not able to carry this beast ...
Have fun,
Toni
LED VU meter on the front RC controlled (2 x 24 leds strobed with 2kHz). Inside the case a RGB led stripe is included. The MCU controller has support for RGB led ...
Have fun, Toni
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Hi all!
Attempting a KSA 100 clone build... recently completed a KSA 50
the modules
Attempting a KSA 100 clone build... recently completed a KSA 50
the modules
Planning to try a new heat sink profile on chassis...
Two heat sinks joined side by side... weighing 5kg per module.
Bottom and back plates 3mm thick...
Face plate 6mm and top plate 3mm...
Two heat sinks joined side by side... weighing 5kg per module.
Bottom and back plates 3mm thick...
Face plate 6mm and top plate 3mm...
Dear hydrovac
can you share the source of Aluminum Plates and that heatsink? if possible.
I haven't find any cut to size plates here in Delhi, sellers are selling whole 8*4feet here in Delhi if I need to get that brushed finish
I need some bottom/top and Back plates 3MM or if possible 5MM thick
for face-plate I need 6-10MM thick
I have these Heatsink in hand, size 300x100x80mm

can you share the source of Aluminum Plates and that heatsink? if possible.
I haven't find any cut to size plates here in Delhi, sellers are selling whole 8*4feet here in Delhi if I need to get that brushed finish
I need some bottom/top and Back plates 3MM or if possible 5MM thick
for face-plate I need 6-10MM thick
I have these Heatsink in hand, size 300x100x80mm

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