Hypex Nilai stereo/mono kits cases

[Chart]

Hi dear members of ASR !

This is my first post here, to ask some informations to Hypex Nilai stereo/mono kits owners. Sorry for my poor english level, I'm french

I plan to buy a Hypex Nilai stereo kit and do some modifications on it (adding a second Nilai PSU to do a dual mono amp). But before buying, I need some mechanical informations (not found elsewhere) to check if my project is possible.

I would like to know the following measurements about the stereo kit :
- thickness of bottom cover
- thickness of top cover
- external height of case, excluding feet and front plate (i.e. distance from top of top cover to bottom of bottom cover)
- remaining free space beetwen highest point at top of PSU and the cover

And if someone own the mono kit :
- thickness of intermediate plate mounted between the bottom cover and the PSU

Many thanks if some people can tell me these numbers !

Chart

 

[Vincentponcet]

Woo, the PSU has nearly the same price as the amp module.
299e vs 429e

 

[Chart]

Yes, it's some money. But stereo kit + second PSu + some screws cost is stil a few bucks below 2 x mono kits price.
Furthermore, WAF constraint is : no mono blocks

 

[NTK]

Be aware that each of the PS500DIY power supply has a 5.5 W idle power loss, which must be dissipated to the amplifier case. By adding one more PS500DIY, you'll need to make sure that the additional heat will not cause you problems.

 

[Chart]

Yes, good advice !

All my hifi and cinema equipment is powered via a master pdu, and remains totally off the grid when not in use.

And to avoid excessive heating during use, I've planned to drill 2 cm diameter vent holes wtih protection grid in the bottom cover :
- 5 holes just below the two PSUs
- 6 holes in proximity of the 2 amps

Equivalent total open surface will be about 35 cm2. Better than nothing, like in the actual bottom cover delivered by Hypex. I Hope it will be enough to evacuate heat with the additional PSU. If not sufficient, I'll add some more holes or increase their diameter.

I don't know if it is necessary to add vent holes on the top cover too.

Anyway, I'm surprised by the lack of vents on the Hypex case design, event with class D and one single PSU...

 

[Chart]

Anybody, of course please do not hesitate to give advice about this idea...

 

[boXem]

Why not asking Hypex/DIYClassD?

 

[NTK]

Some back-of-the-envelop calculations to compare a dual mono Nilai against a stereo NC252MP.

For the Nilai, each PS500DIY has an idle loss of 5.5 W; and the amplifier section has an idle loss of 2.25 W per channel. Therefore, the total loss = 2 X (5.5 + 2.25) = 15.5 W.

For the NC252MP, the PS section idle loss is 8.5 W and the amplifier section idle loss is 3.5 W per channel. Therefore, the total loss = 8.5 + 2 X 3.5 = 15.5 W.

Many of the commercial NC252MP implementations use smaller cases than the stereo Nilai case. I think you'll be fine if you place your amp in a well ventilated place.

 

[Chart]

Why not asking Hypex/DIYClassD?

Already done, but about general principle to add a second PSU and the way to start the second amp from the first one. To summarize their answer in a few words : It should work without problem, but they do not support this configuration.

But I haven't asked them precisely about thermal considerations. I should have...

 

[Chart]

Some back-of-the-envelop calculations to compare a dual mono Nilai against a stereo NC252MP.

For the Nilai, each PS500DIY has an idle loss of 5.5 W; and the amplifier section has an idle loss of 2.25 W per channel. Therefore, the total loss = 2 X (5.5 + 2.25) = 15.5 W.

For the NC252MP, the PS section idle loss is 8.5 W and the amplifier section idle loss is 3.5 W per channel. Therefore, the total loss = 8.5 + 2 X 3.5 = 15.5 W.

Many of the commercial NC252MP implementations use smaller cases than the stereo Nilai case. I think you'll be fine if you place your amp in a well ventilated place.

Nice way to analyze the question, by comparison with other hypex modules with same idle losses. Many thanks !

 

[Chart]

Hi !
I've finished the assembly of my dual mono hypex nilai.
A few things to improve (mainly cable management), but it already works very nice. It will replace an 15 years old Cambridge which needs some repairs.

 

[Marquant]

Hi !
I've finished the assembly of my dual mono hypex nilai.
A few things to improve (mainly cable management), but it already works very nice. It will replace an 15 years old Cambridge which needs some repairs.

View attachment 336232

Looking good! So you added an extra psu to the nilai stereo kit? Or did you use another case? (Ghentaudio?) Any problems/solutions you'd like to share?

 

[HoweSound]

Nicely done! I have the Nilai stereo amp - very happy with it, but, if I could do it over, I would have bought the Audiophonics HPA-S300NIL, because of the better case and I'm sure, better cooling.

AUDIOPHONICS HPA-S300NIL Power Amplifier Nilai500DIY

Hand-assembled in our workshop in France, the Audiophonics HPA-S300NIL power amplifier is a high-performance dual-mono model based on the new Hypex Nilai500DIY amplifier. This delivers high power output with very low noise for precise sound.

www.audiophonics.fr

 

[Chart]

Looking good! So you added an extra psu to the nilai stereo kit? Or did you use another case? (Ghentaudio?) Any problems/solutions you'd like to share?

It's the original case from the "official" Nilai stereo kit from ClassDIY, with a second PSU I've added.

Main (small) concern was to be sure that the second PSU would fit with enough clearance between the top cover and the top of the PSU. Internal case dimension are not in the datasheet of the kit, neither the thickness values for the top and bottom cover.

I didn't wanted to mount the PSU directly on the bottom cover, because I don't own tools (and I'm not able) to drill holes with 0.5mm precision and there are 7 holes to mount each PSU...
I've designed and ordered a custom aluminium plate on a german web site. This 3mm thick intermediate plate has 14 holes corresponding to the 2 PSU fixing schematics, and 7 more holes corresponding to existing holes on the bottom cover (originally used to mount the single PSU). 5 vent holes (20mm diameter) were drilled in the plate and the bottom cover just below the PSU. I've also drilled 4 vent holes besides the Amps modules too.

When purchased alone, Hypex nilai PSU does not include the J2-HBUS harness (only J5-User IO, AC and amp module cables). I've ordered a Nilai harness on Ghent shop to daisy chain the first PSU J2-HBUS +18v auxiliary pin to J5-User IO trigger input of the second PSU. I've made a "dirty" cable with diod to lower a bit the voltage (cause trigger input max voltage is 18v). Maybe a 18v relay or an opto would be better... Don't know, and it works fine as it is...

Conclusion : no big problems to realize this tweak, as soon I was sure all gear will fit in the case and interconnect well.

 

[Chart]

Nicely done! I have the Nilai stereo amp - very happy with it, but, if I could do it over, I would have bought the Audiophonics HPA-S300NIL, because of the better case and I'm sure, better cooling.

AUDIOPHONICS HPA-S300NIL Power Amplifier Nilai500DIY

Hand-assembled in our workshop in France, the Audiophonics HPA-S300NIL power amplifier is a high-performance dual-mono model based on the new Hypex Nilai500DIY amplifier. This delivers high power output with very low noise for precise sound.

www.audiophonics.fr

I think you're right about better cooling of Audiophonics stereo case. Hypex case has not a lot of vent holes, and I've drilled some on the bottom cover to have more air convection with the second PSU added heat. At the moment, my dual mono is baerly hot after a few hours of listening... Hope it will be ok this summer too...

I've had a close look on HPA-S300NIL before buying the Hypex stereo kit from ClasseDIY. But with the 2 big heatsinks inside Audiophonics case, there is not enough room left to add a second PSU.

 

[Marquant]

It's the original case from the "official" Nilai stereo kit from ClassDIY, with a second PSU I've added.

Main (small) concern was to be sure that the second PSU would fit with enough clearance between the top cover and the top of the PSU. Internal case dimension are not in the datasheet of the kit, neither the thickness values for the top and bottom cover.

I didn't wanted to mount the PSU directly on the bottom cover, because I don't own tools (and I'm not able) to drill holes with 0.5mm precision and there are 7 holes to mount each PSU...
I've designed and ordered a custom aluminium plate on a german web site. This 3mm thick intermediate plate has 14 holes corresponding to the 2 PSU fixing schematics, and 7 more holes corresponding to existing holes on the bottom cover (originally used to mount the single PSU). 5 vent holes (20mm diameter) were drilled in the plate and the bottom cover just below the PSU. I've also drilled 4 vent holes besides the Amps modules too.

When purchased alone, Hypex nilai PSU does not include the J2-HBUS harness (only J5-User IO, AC and amp module cables). I've ordered a Nilai harness on Ghent shop to daisy chain the first PSU J2-HBUS +18v auxiliary pin to J5-User IO trigger input of the second PSU. I've made a "dirty" cable with diod to lower a bit the voltage (cause trigger input max voltage is 18v). Maybe a 18v relay or an opto would be better... Don't know, and it works fine as it is...

Conclusion : no big problems to realize this tweak, as soon I was sure all gear will fit in the case and interconnect well.

Thanx!

Indeed it seems that the HPA-S300NIL is just too small inside :-(

 

[Deleted member 48726]

Nicely done! I have the Nilai stereo amp - very happy with it, but, if I could do it over, I would have bought the Audiophonics HPA-S300NIL, because of the better case and I'm sure, better cooling.

AUDIOPHONICS HPA-S300NIL Power Amplifier Nilai500DIY

Hand-assembled in our workshop in France, the Audiophonics HPA-S300NIL power amplifier is a high-performance dual-mono model based on the new Hypex Nilai500DIY amplifier. This delivers high power output with very low noise for precise sound.

www.audiophonics.fr

It's a nice case and nice electronics. BUT it grinds my gears that the radiators are not used for anything but aesthetics and that they write this at the same time:

The chassis, entirely designed in sand-blasted aluminum, is equipped on its sides with two imposing radiators capable of efficiently dissipating heat. In addition, carefully distributed ventilation holes promote air circulation and heat dissipation. The heat sinks also contribute to the amplifier's solid, modern aesthetic.

 

[Chart]

I don't own an IR cam, therefore I can't know the components temp.

But I've set a temperature sensor inside my case, just under the top cover, beetween PSU and Amp module. Temp probe has no contact with anything, the measured value is the air temp inside the case.

After 3 hours of music listening, air temp inside the case has stabilized at 39° celsius. Room ambient temp was 19°.

Too hot or ok ?

 

[Deleted member 48726]

I don't own an IR cam, therefore I can't know the components temp.

But I've set a temperature sensor inside my case, just under the top cover, beetween PSU and Amp module. Temp probe has no contact with anything, the measured value is the air temp inside the case.

After 3 hours of music listening, air temp inside the case has stabilized at 39° celsius. Room ambient temp was 19°.

Too hot or ok ?

That depends on what is the main "heat provider" inside the amp.

It is most likely fine but I have seen pictures of small components reaching very high local temperatures in some of the Class D threads..

 

[Smoey22]

Hi,

I've recently done the same modification to my own amplifier. I used @Chart's .fpd-file as template and went for a more basic design:

• 3 mm black anodized base plate
• 7x M3-threads
• 14x M3-holes, countersunk

The plate was manufactured by Schaeffer AG (Germany).
I have attached a picture of the amplifier before the modification, the custom mounting plate, and two photos of the finished project.

I bought the screws for mounting the new plate to the primary plate from Accu.co.uk, went for black stainless steel (M3 x 10 mm).
I think that seven steel screws in 3 mm alloy threads is secure enough, blue Loctite could maybe be an option. But if the threads strip I have 3 mm protruding threads that I can tighten with the nuts and washers similar to your case. See attached screw order.

I ordered a mains Y-cable and a harness-kit from Ghentaudio, connected J2 - J5 (18 V).
I've also ordered some thin thermal pads (0.5 mm) to enhance heat transfer between the two plates. However, I'm undecided about installing them since the Schaeffer plate already ensures a solid contact due to its precise manufacturing tolerances.

The amplifier drive two DIY-speakers, Toids Epic HiFi Speaker.
Pushed them to 110 dB @ 45 Hz the other day, don't need more power anytime soon, that's for sure. I've also stress tested the amplifier in a party setting, averaging 105 dB on the "dance floor" for 4 hours, the amplifer got hot, but no harm done, although clipping was not very far away with some songs.
Those speakers can become quite boomy in my living room, therefore I have applied minimum phase filters (0 - 225 Hz) using @OCA's tutorial, easy to understand and very effective at correcting bass response, highly recommend.

Cheers!