DIY Purifi Amp builds

[JimB]

Yes, I'm sorry for the confusion.

My current amp has manufacturer branded "custom buffers" which I think are the just the NC500 evaluation boards made by Hypex. https://www.hypex.nl/product/nc500-evaluation-board/51

My question is about the ease of replacing those with Neurochrome input buffer, and whether that could be a plug and play part replacement. https://neurochrome.com/products/purifi-1et400a-hypex-nc500-input-buffer

I wasn't sure if this thread or the input buffer thread was more appropriate. The input buffer thread pertains to performance, and my question pertained to the DIY upgrade to the Neurochrome buffer. It was 50/50.

Ahhh. What amp modules are in that amp?

 

[AndrewDavis]

Ahhh. What amp modules are in that amp?

Oh, of course! Haha. Its a Purif 1ET400A. I got that much right!

 

[March Audio]

Yes, I'm sorry for the confusion.

My current amp has manufacturer branded "custom buffers" which I think are the just the NC500 evaluation boards made by Hypex. https://www.hypex.nl/product/nc500-evaluation-board/51

My question is about the ease of replacing those with Neurochrome input buffer, and whether that could be a plug and play part replacement. https://neurochrome.com/products/purifi-1et400a-hypex-nc500-input-buffer

I wasn't sure if this thread or the input buffer thread was more appropriate. The input buffer thread pertains to performance, and my question was about a DIY upgrade to the stock buffer. It was 50/50, lol.

Hi Andrew

Just a note on that Hypex eval buffer. Its not suitable for a final product. Evaluation and development yes, product no. Reason being is that it has no input filtering or GBW limiting. Its wide open. It will work, but has potential to pick up all sorts of crap and cause issues. It also has very ordinary voltage regulation which has very little rejection at the switching frequency of the SMPS.

 

[AndrewDavis]

Hi Andrew

Just a note on that Hypex eval buffer. Its not suitable for a final product. Evaluation yes, product no. Reason being is that it has no input filtering or GBW limiting. Its wide open. It will work, but has potential to pick up all sorts of crap and cause issues.

Thank you Alan!! You identifying these issues is exactly the reason I'm interested in replacing them.

If I was in the market today I'd just get a P452 and be done with it.

 

[JimB]

Oh, of course! Haha. Its a Purif 1ET400A. I got that much right!

Then I think this is a good place to get your answers!

 

[JimB]

Thank you Alan!! You identifying these issues is exactly the reason I'm interested in replacing them.

If I was in the market today I'd just get a P452 and be done with it.

So, yes, the new Neurochrome buffer is superior. And I'm sure it can be used. But, I can't say if it is a "drop-in replacement" for what you have without looking at each connection point/option on the two boards (plugs, pin-outs, etc). I have neither of them, so others will have to advise you on the exact steps that would be needed if you cannot do that yourself. Maybe @tomchr?

 

[AndrewDavis]

Thanks a lot!! Here are a couple pictures off the web, if it's useful. I asked Warren (VTV) and he confirmed that they use the Hypex NC500 evaluation boards. That one is on top and the beautiful Neurochrome Blue one on the bottom is from Neurochrome.

 

[avagadro]

Aside from ease of wiring, is an input buffer required to build a decent sounding 1et400 mono amplifier? It seems possible to equip all the protective functionalities in combination with Hypex SMPS600/1200

Apologies if this is a noob question, I've went thru several threads looking for clarity on this for a monoblock build. I've understand from March and others there are sonic gains to be had with additional input filtering and improved voltage regulation, but is it necessary to build a decent sounding, SAFE, proof-of-concept mono amp?

 

[JimB]

Aside from ease of wiring, is an input buffer required to build a decent sounding 1et400 mono amplifier? It seems possible to equip all the protective functionalities in combination with Hypex SMPS600/1200

Apologies if this is a noob question, I've went thru several threads looking for clarity on this for a monoblock build. I've understand from March and others there are sonic gains to be had with additional input filtering and improved voltage regulation, but is it necessary to build a decent sounding, SAFE, proof-of-concept mono amp?

Do you mean just a 1ET400A, alone? You MUST provide some input/power functions. The EVAL1 and EVAL2 do that, as do some other, 3rd party input buffer boards that provide for required interfacing to some degree.

You CAN run a high level input signal to the 1ET400A, directly. The EVAL boards have jumpers for exactly that.

P.S. What's your number? As a chemist, I couldn't resist.

 

[tomchr]

My current amp has manufacturer branded "custom buffers" which I think are the just the NC500 evaluation boards made by Hypex. https://www.hypex.nl/product/nc500-evaluation-board/51

My question is about the ease of replacing those with Neurochrome input buffer, and whether that could be a plug and play part replacement. https://neurochrome.com/products/purifi-1et400a-hypex-nc500-input-buffer

My Purifi/Hypex Buffer is a different physical size than Hypex’s board, so the mounting holes won’t be aligned. You’ll also need a 10-pin ribbon cable (Hypex in their infinite wisdom put a 10-pin connector on one end of the cable and a 16-pin on the other for some bizarre reason). Those things aside, it’s plug-n-play. You can buy the ribbon cables pre-made from Mouser and Digikey if you wish, or you can make your own. It’s pretty easy.

Tom

 

[AndrewDavis]

My Purifi/Hypex Buffer is a different physical size than Hypex’s board, so the mounting holes won’t be aligned. You’ll also need a 10-pin ribbon cable (Hypex in their infinite wisdom put a 10-pin connector on one end of the cable and a 16-pin on the other for some bizarre reason). Those things aside, it’s plug-n-play. You can buy the ribbon cables pre-made from Mouser and Digikey if you wish, or you can make your own. It’s pretty easy.

Tom

Awesome Tom. Thank you. I can manage a couple holes in an aluminum case and a ribbon cable. This skill-less music lover appreciates your help!!!

 

[tomchr]

You're welcome.

And, actually... If you have the Hypex cable, you can just add a 10-pin connector to it. The IDCs (insulation displacement connectors) make that really easy.

Tom

 

[phoenixdogfan]

Do you mean just a 1ET400A, alone? You MUST provide some input/power functions. The EVAL1 and EVAL2 do that, as do some other, 3rd party input buffer boards that provide for required interfacing to some degree.

You CAN run a high level input signal to the 1ET400A, directly. The EVAL boards have jumpers for exactly that.

P.S. What's your number? As a chemist, I couldn't resist.

Should be 6.022 x 10 23rd power.

 

[JimB]

Ghent shared a photo of a completed amp with the stock EVAL1 board set PLUS speakON connectors! So, I think they will be available to order soon. I believe they will be offered with all required cables, in which case people who just want to assemble will now have an option. There's even a simple way one could connect the speakONs without soldering (requires a special jumper cable, maybe not from Ghent). I hope pricing will be similar to their other cases.

Now, where are mine with binding posts?

 

[cooldude]

Anyone have recommendation for a 7 channel chassis and have a usable cad

 

[phoenixdogfan]

Ghent shared a photo of a completed amp with the stock EVAL1 board set PLUS speakON connectors! So, I think they will be available to order soon. I believe they will be offered with all required cables, in which case people who just want to assemble will now have an option. There's even a simple way one could connect the speakONs without soldering (requires a special jumper cable, maybe not from Ghent). I hope pricing will be similar to their other cases.
View attachment 88219

Now, where are mine with binding posts?

Wish he would have offerred it 6 months ago.

 

[mocenigo]

Anyone have recommendation for a 7 channel chassis and have a usable cad

MODU has some large cases. I would use Tom Christiansen’s mono buffer/adapter boards. They are good. You can probably get a good quote for seven. Maybe even ask him if he can provide little daughter boards based on parallel LM3045/3049 (not sure about the name) regulators. Or just use the Hypex ones, they are great.

Get a hypex 3kw power supply. In theory not sufficient for 7 Hypex modules but since some will be satellites and not all will carry the same bass power, it will definitely be ok. Remember to connect 3 or 4 audio boards out of phase both in inputs and speaker outputs to mitigate pumping.

Have a metal shop cut you seven L shaped aluminum pieces (I would suggest 4mm thick) or even steel, to mount the boards vertically.

As for the CAD you can use this one https://www.schaeffer-ag.de/en/front-panel-designer#download
It is sufficient for the front and back panels.
Here http://www.hifi2000.it/default.asp?id=0&ACT=19 there are their own panels. Useful as a starting point. There are also some free cad programs. QCAD comes to mind.

Once you have chosen your connectors, make sure you find the right measuremements. Neutrik has full CAD designs on their web site, for instance.

oh yes, the cover of the modu cases can be a bit wobbly - even with 3mm of aluminium, they are large! and therefore I suggest to add a little reinforcement with a little L shaped piece affixed to the middle of the back side, both above and below, and to mount everything on the optional perforated steel plate. Ask for the covers with slits, for instance at the bottom. I had slits also on the back plate instead of the top one, but with seven modules...

last suggestions, get a few NOCTUA fans, these are completely silent. For instance run the 80mm 12V ones at 9V and place a couple in the case.

payment for this service: a smile

 

[mocenigo]

Wish he would have offerred it 6 months ago.

yeah. But I would have had less fun!

 

[cooldude]

https://diyaudiostore.com/collections/accessories/products/riser-panels

Thninking about these to mount modules vertically

 

[mocenigo]

https://diyaudiostore.com/collections/accessories/products/riser-panels

Thninking about these to mount modules vertically

A bit thin. Any shop making metal cuts can make something of the right side, maybe 3-4 mm thick, and with holes for screws.