A custom chassis would be nice. Not sure we can get 100 people though. Maybe 24?
This amp works very well and can be part of the larger overall Ecosystem of Class A that JPS64 mentioned. Separate boards that all come together for a fantastic sounding and easy to build and setup amp:
- SLB dual rail PSU
- Alpha Nirvana amp and snubber boards
- SSR DC protection boards (note that Alpha Nirvana has built in power jack for SSR)
- the yet to be developed Soft Start board that JPS64 mentions
- the Custom HiFi2000 chassis.
Btw, it seems to work at 4U x 300mm in winter here in Virginia (68 F basement) with 55C heatsink temps. But I feel that a 5U would be much more comfortable and drop it down to 40’s C.
I am going to add the SSR’s to my build next. Shouldn’t take more than 5 to 10 minutes to install.
This amp works very well and can be part of the larger overall Ecosystem of Class A that JPS64 mentioned. Separate boards that all come together for a fantastic sounding and easy to build and setup amp:
- SLB dual rail PSU
- Alpha Nirvana amp and snubber boards
- SSR DC protection boards (note that Alpha Nirvana has built in power jack for SSR)
- the yet to be developed Soft Start board that JPS64 mentions
- the Custom HiFi2000 chassis.
Btw, it seems to work at 4U x 300mm in winter here in Virginia (68 F basement) with 55C heatsink temps. But I feel that a 5U would be much more comfortable and drop it down to 40’s C.
I am going to add the SSR’s to my build next. Shouldn’t take more than 5 to 10 minutes to install.
5U would be more suitable for people like me, living in tropical asia.
We have to cool down our room all year round just to be able to enjoy ClassA amps.
HeHe!!Since I already have a pair of 300va, 24v Anteks, I’ll probably go dual mono with a pair of SLB’s.
The 5u 400mm has lots of real estate.
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You guys are amazing and it blows my mind how fast you all are coming up with new designs. On sadder note, the Panasonic ERX is coming up as "not recommend for new designs" which I believe means they are not going to be producing it much longer.
How does the alpha nirvana compare to the alpha 20?
Will this amp be available on your Etsy page X?
How does the alpha nirvana compare to the alpha 20?
Will this amp be available on your Etsy page X?
Yes, once we confirm the prototype is good it will be available for ore-orders as a GB - and anything remaining after.
We have switched to KOA BPR series non-inductive current sense resistors instead of Panasonic ERX. They handle 5w and are actually more compact from real estate standpoint. That’s what’s is used here on the Nirvana.
We have switched to KOA BPR series non-inductive current sense resistors instead of Panasonic ERX. They handle 5w and are actually more compact from real estate standpoint. That’s what’s is used here on the Nirvana.
Hugh, good luck with your commercial offering based on this work, it sounds like you are well into it already.
X, as I mentioned in a previous post, after you have finished your testing, I think it would be a good idea to do a chassis wiring diagram as you have built it, so that members have a head start when using your dual SLB, AN amp boards and SSR boards, especially as you had some hum and that is now sorted with different wiring connections.
I would be up for a dedicated chassis for this design, but already have dual SLB and SSR boards, so maybe options if you are looking at that seriously will be the way to go, rather than a no option complete package.
Regards,
Gary..
X, as I mentioned in a previous post, after you have finished your testing, I think it would be a good idea to do a chassis wiring diagram as you have built it, so that members have a head start when using your dual SLB, AN amp boards and SSR boards, especially as you had some hum and that is now sorted with different wiring connections.
I would be up for a dedicated chassis for this design, but already have dual SLB and SSR boards, so maybe options if you are looking at that seriously will be the way to go, rather than a no option complete package.
Regards,
Gary..
Hi Gary,
Will get hookup diagram as soon as I have some time. I think we will probably be going with the individual smaller boards option to keep it fun - you can add/remove options as you see fit. Also, let’s you re-use your existing hardware like and SLB or SSR protection board.
Cheers,
X
Will get hookup diagram as soon as I have some time. I think we will probably be going with the individual smaller boards option to keep it fun - you can add/remove options as you see fit. Also, let’s you re-use your existing hardware like and SLB or SSR protection board.
Cheers,
X
Here is how I connected the Alpha Nirvana with the SLB and my chassis. The one wire from RCA (L) ground to the star GND hub is optional. It reduced the amount of hum ever so slightly. The RCA ground is electrically isolated from the chassis panel via the shoulder washers that come with it.
Here is the 300w 10ohm load resistor connected to a CPU cooler heatsink:
Here is clipping performance of this amp with a 300w 10ohm ultra-low inductance resistor. A nice symmetric and clean clip at 54.6vpp:
Here is the output just before the onset of clipping (53.4vpp) which would be about 46.5w into an 8ohm load:
46w from 94w thermal dissipation is 49% efficiency - very good for a SEPP amp.
Continuing to do more long term listening. The soundstage and imaging are excellent.
Here is the 300w 10ohm load resistor connected to a CPU cooler heatsink:
Here is clipping performance of this amp with a 300w 10ohm ultra-low inductance resistor. A nice symmetric and clean clip at 54.6vpp:
Here is the output just before the onset of clipping (53.4vpp) which would be about 46.5w into an 8ohm load:
46w from 94w thermal dissipation is 49% efficiency - very good for a SEPP amp.
Continuing to do more long term listening. The soundstage and imaging are excellent.
Attachments
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Each board has a power earth (PE) spade connector (X1) - it’s located right next to the black disc (NRC). This is connected to the board’s 0v analog ground via an NTC (8D-20 or CL60) and typically a 0.022uF 250v MKP cap. On the Alpha Nirvana, it is a 0.022uF 600V X7R SMT cap I think. This cap and NTC (nominally 8 to 10ohms when cold) serves as a ground loop breaker for each board. If there were to be a fault, and large current flows through the NTC, it would heat up and drop to about 0.5ohms to safely conduct the fault to the chassis earth ground f.
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Thanks X,
Great information to assess the tech specs of this extraordinary amp.
BTW, you may not need a single wire of ONE channel from the RCA ground to SLB ground; the braid RCA COAX on each channel should pass to the signal earth of each amp module. Put another way, if you disconnect your one wire from ONE RCA ground to SLB ground, it may actually reduce hum. With it there, the 10R float resistor is bypassed. However, earthing is a black art, and hell, I may be quite wrong........
HD
Great information to assess the tech specs of this extraordinary amp.
BTW, you may not need a single wire of ONE channel from the RCA ground to SLB ground; the braid RCA COAX on each channel should pass to the signal earth of each amp module. Put another way, if you disconnect your one wire from ONE RCA ground to SLB ground, it may actually reduce hum. With it there, the 10R float resistor is bypassed. However, earthing is a black art, and hell, I may be quite wrong........
HD
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Not for current source loaded output stages!
You might approach 50% when replacing the current source with an inductor.