Brainstorming Purifi 1et400a amps

Had a AHB2 and sold it for a Mark Levison integrated 585, to simplify all the components. And it is a good integrated but the amp part is not as good as the AHB2 was. Still have the DAC2HGC of which I used as a preamp. So looking for a project, I have built Pass and lots of speakers but have not played around with class D.
Jim
 
So a little SMPS followed by a DC-DC converter, such as a dual TRACO with +-15V should work, and then a little CLC filter to kill the HF noise and smooth the residual ripple (which is at around 100mV). I would probably not do more mostly because I would not feel that comfy putting, say, another regulator with the little tantalum and 2 resistors to further clean everything.

Roberto
Sounds like a neat plan.
 
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Correct. The EVAL1 board would be the adapter board, in a sense

Also, the trick of using a "naked" XLR male plug to connect is very neat. I can start with that and longer wires to connect to the case, and then addind the Neurochrome buffer would be just a matter of cutting those wires, strip them, insert in the terminals and screw them!

I am still undecided about the PS for the neurochrome. A little silent, potted toroidal, maybe in a mumetal box, plus the SALAS board, would be the easiest route. But a dual one would mean 128 x 85 mm (and the height?) plus the transformer, so I would have to revise my current thoughts for the case size.
I wonder if I could mount the neurochrome buffer at least partially above the EVAL1. This would allow me to save a bit on the case depth. In this case I would have to "snip" the XLR connectors. Mh
 
Does the module change modes when the bypass is used?
Also, since it seems there is gain obtained from the control board doesn't that make it a type of pre-amp as opposed to buffer?
Thanks,
Dave in MN

I don't know what the board does but given that software mode is enabled with a resistor I doubt it changes.
However, software mode doesn't actually allow you to control anything on the board, it is for monitoring only.

I guess there are buffers with gain and pre-amps with no gain so you can decide what you want to call it :)
 
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Does the module change modes when the bypass is used?
Also, since it seems there is gain obtained from the control board doesn't that make it a type of pre-amp as opposed to buffer?
Thanks,
Dave in MN

I would say that the pre-amp is the whole product, and the buffer is a sub-system. Buffers are electrical impedance transformation that circuits that prevent the source to be driven by the load. Buffers come with various levels of gain, some at unity, some quite high. Many preamps are input buffer+attenuator+output buffer. There are buffer-less preamps (passive ones, i.e. just attenuators) and preamps that rely on buffers with variable gain. And more design with non-adapting components, and preamps that include a phono stage and so on.

So the EVAL1 control board is just a control board with a buffer (with gain), not a preamp.
 
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Well ordered the Puifi EVAl1, and a Hypex SMPS 1200A400, and will order the DIY Pesante 3U chassis 120mmHx430mmWx300mmD. Will post stuff if and when receive parts. Audio is my passion my wife says it's my obsession and of course she is right.
Jim

You lucky man. My wife has been patient with me playing a LOT with my audio system and even setting up a new one in the living room (gasp!). But it seems that I will have to wait a bit with my Purifi build... Probably Purifi will have their own SMPS by then and maybe revised evaluation boards.
 
I am hoping...

or even expecting, that some enterprising engineer/hobbyist will design and build some alternative input modules for the Purifi modules. Personally I would prefer to be able to implement full dual mono construction (not possible via the current eval boards).

Additionally, I would like to see someone develop a really good discrete circuit for this. The physical similarity to the NC500 modules is intriguing, pinouts may be the same? If so, input boards from Nord, Appollon, etc may work. Of course both of these companies are already selling finished Purifi based amps, right?

I think there are a lot of folks who might like to do mono block builds as well...

I suspect there would be a healthy market for an enterprising and talented designer to offer input boards for the Purifi modules for DIY users.
 
or even expecting, that some enterprising engineer/hobbyist will design and build some alternative input modules for the Purifi modules. Personally I would prefer to be able to implement full dual mono construction (not possible via the current eval boards).

Additionally, I would like to see someone develop a really good discrete circuit for this. ...

I (and likely many others) suggested to Purifi that a single channel "EVAL" board would be of great interest to the DIY market. Purifi has it on their list of things to consider when they have time.