2. amps-preamps
  3. 162284-76532

Purifi Class D: Junk?

So, from the previous thread about high-end class D the Purifi module was brought up. I decided to get a cheap example from VTV, a simple stereo unit with a single Purifi module and matching Hypex SMPS. Standard input buffer. I got it in yesterday. First impression wasn't what I was expecting: weak, congested dynamics is what stood out to me. I expected greater expression through my ProAc D30Rs. The other problems such as poor soundstage, thin / boring character, etc, I marked up to needing burn-in before evaluating. So it's been 24 hours, I would still expect to get at least the high control / damping of high end class D and dynamic power, but it's just not present.

Could it be an impedance mismatch? Other manufacturers selling the Purifi with their custom input buffers are reporting 47k Ohms. VTV doesn't say in the manual or on the site. I checked the Purifi data sheet which reports...2.2k Ohms on SE???? That can't be right?? That's absurdly low! Am I reading the right spec? My preamp has an output impedance of 230 Ohms. Can someone confirm that the stock Purifi has this ultra-low input impedance?
madavid0

Showing 3 responses by mike_in_nc

mike_in_nc
1,121 posts
 
To the OP:
Calling PuriFi "junk" because you don’t like something you bought that has PuriFi modules in it makes no sense. I bought some iced tea that tasted bad. Does that mean tea is junk? Water is junk?

You don’t like the amps you bought, understood. Please leave it at that. You now have a problem to solve, whether it’s with the amps you bought, with the vendor, with something else in your system, or just with system synergy. No use slinging mud -- it won’t help solve it.

mike_in_nc
1,121 posts
 
I have listened quite carefully to a pair of monoblocks made by Apollon Audio using the PuriFi modules. In my system, in my room, with my own source material, I consider them in the same league as the well-respected Class AB amp I normally use -- I might wind up liking them better. As a frame of reference, the AB amp has an MSRP more than twice what I paid for the monoblocks, delivered. (I don’t intend a value comparison -- there are reasons for the cost differential, at least some of which involve value added, such as dealer support, longer warranty, and so on. Just to say it’s not a low-cost item.)
Oh -- I don't think either the AB or the PuriFi amps are "junk."
mike_in_nc
1,121 posts
 
@jaytor -- You have a wonderful touch with the DIY projects. If I had the skill and patience to make things so neat and beautifully laid out, I’d be a DIYer myself.

As someone interested in those PuriFi modules, I’ll be very interested in how you like the Weiss op amps. Please do post and let us know.

I believe the Weiss are not plug-compatible with the Sparkos and Sonic Imagery units. Is that right?
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