Audiophonics HPA-S400ET Review (Stereo Amplifier)

[Rja4000]

1000 thanks @amirm for this review !

Nice to see this one tested !
I've been balancing for a while about buying it.
It's just that I don't NEED it.

I'm very curious to see how the cheaper/smaller one would perform.
I don't really like its layout though.

 

[Matias]

One question though is what caps did it use?

Oh please don't open that can of worms. Read this thread instead.

Apollon Hypex NC2K Amplifier Teardown

This is a tear down of the recently reviewed Apollon NC2K monoblock amplifier. Both the owner and the company gave kind permission to do this. As you all know, the heart of these amplifiers are power supply and amp modules provided by Hypex to its OEMs. There are some optional parts however...

www.audiosciencereview.com

 

[KMO]

Why is it so hard to add a gain selector knobs on the back, it's just some simple wires changing the way the jumper pins are short circuited.

Yes, this is the pretty much the only thing letting it down. A bit cheap for a four-figure product. Everything else is present and correct. It's not as if there's no space for a switch...

There are European competitors who do manage that, but then they've not managed to get those units to Amir for review. Examples:

Apollon 1ET400A mini or multichannel (12.8/20.5/27.5/29.0dB, per channel pair)

Vera Audio P150/600 RS (12-30dB in 3dB steps, per channel)

I also believe neither of those actually bypass the input buffer for low gain - so you always get a high-impedance load.

 

[pma]

Agreed. Besides, Purifi advertises much better THD VS Frequency behaviour...View attachment 194367

Interesting.

 

[Matias]

Agreed. Besides, Purifi advertises much better THD VS Frequency behaviour...View attachment 194367

Purifi is most likely using around 22 kHz bandwidth, which represents actual human hearing, and not Amir's 45 kHz bandwidth, which captures the rise in noise above 22 kHz and makes THD+N increase in high frequency signals.

The low noise in the listening band and higher noise outside it is a conscious design choice according to Bruno in one of his interviews. Makes all sense to me.

 

[KxDx]

$1,700 - damn good deal. Shows that you don't need to spend $tupid money to buy a SOTA amp with lots of power. What are the companies providing that are charging $25k and up for a power amp? Lots of them out there.

Pretty blue VU meters.

 

[beagleman]

Really great performance, but gave is a "Just" fine, based on construction looking rather low cost in "Some" ways, and how it seems not so much not a good value, but fairly high priced for "What it is", meaning, Great I would reserve for it being at least a few hundred dollars less or so.

Being someone that can DIY, and has an Electrical Engineering background etc, I simply do not "See" a lot of expensive stuff in that half empty box to really justify the price (completely)

 

[Bouteille]

Really great performance, but gave is a "Just" fine, based on construction looking rather low cost in "Some" ways, and how it seems not so much not a good value, but fairly high priced for "What it is", meaning, Great I would reserve for it being at least a few hundred dollars less or so.

Being someone that can DIY, and has an Electrical Engineering background etc, I simply do not "See" a lot of expensive stuff in that half empty box to really justify the price (completely)

True, had the same feeling before buying, and was keen on buying separate parts and build myself...
It came to about same price though... The 'ready to use' metal box is veeeeery expensive (~200USD) so if you find/adapt a good one it might become a good option.

 

[Interference]

Well, you can volume matched at least. A well design XLR or differential amplifier has darker back ground. It's really show in the noise level. Subjectively RCA is more simple in design and more lively. It is just harder to suppress the noise. XLR also has a flaw in real world, the signal don't get to sum perfectly to get rid of noise and alter original signal. In real world, no one hand down one another. It is up to designer skill. I would really ask them about which connection is better. Brand like Mark and Krell are by default sound best in XLR pre/power. It is like some manufacturers are hardcore Class A amp than Class AB amps.

Voltage drop shouldn't be a concern, just ask. If RCA better for subjective good sound, it does save you money. For me, I just use over spec cable.

It is not very clear what "darker back ground" or "more lively" means in common terms. This is all about your subjective evaluation, and others may have (and do have) different opinions.

On the other hand balanced operation has been always recommended for Hypex and Purifi designs, and accordingly advocated for in a famous article by B. Putzeys (The G Word, or How to Get Your Audio off the Ground).

 

[KxDx]

Yes, this is the pretty much the only thing letting it down. A bit cheap for a four-figure product. Everything else is present and correct. It's not as if there's no space for a switch...

There are European competitors who do manage that, but then they've not managed to get those units to Amir for review. Examples:

Apollon 1ET400A mini or multichannel (12.8/20.5/27.5/29.0dB, per channel pair)
View attachment 194373
Vera Audio P150/600 RS (12-30dB in 3dB steps, per channel)
View attachment 194372

I also believe neither of those actually bypass the input buffer for low gain - so you always get a high-impedance load.

This is why I'm hoping to hold off until Parasound adopts Class D. They have variable gain pots, audio sensing turn on, selectable high pass, and A/B speaker switching on the New Classic amps. If it had balanced inputs my 2250 would be damn near perfect for my needs.

 

[Bouteille]

Purifi is most likely using around 22 kHz bandwidth, which represents actual human hearing, and not Amir's 45 kHz bandwidth, which captures the rise in noise above 22 kHz and makes THD+N increase in high frequency signals.

The low noise in the listening band and higher noise outside it is a conscious design choice according to Bruno in one of his interviews. Makes all sense to me.

Thank you for the clarification, pushing noise to non-audible part of spectrum can indeed be a design strategy.
I think I read that for DACs mainly (I am no expert, apologies if incorrect).

 

[F1308]

So, going from AHB2 to HPA-S400ET will halve your spending.
Happy ?
Wait a minute !
Go from HPA-S400ET to PA5 and you will be spending a fifth.
Hey, a tenth from the starting point.

I have to cheer all of those great companies and thank them for their astounding achievements.

Wondering if power will be enough?
I can go deaf already with my Topping PA5, no more power needed whatsoever bearing in mind my loudness go as follows: songs are 100 out of 127, the system keyboard is 100 out of 127, master general volume is 50 out of 100 and finally PA5 is 75 out of 100. Seems like using a little bit more than 23%...

 

[kongwee]

It is not very clear what "darker back ground" or "more lively" means in common terms. This is all about your subjective evaluation, and others may have (and do have) different opinions.

Yup, subjective evaluation and understand the design strength. Especially design part, you can go to hifi show and ask dealers and even the CEO/designers to talk about it. Then you will understand what is their decision in design. They have their own preference and how a setup should be. Even prefer which brand to go with their product or what products are used evaluating their design.

 

[Angsty]

Is Cambridge Audio reading this review?

 

[PeteL]

Really great performance, but gave is a "Just" fine, based on construction looking rather low cost in "Some" ways, and how it seems not so much not a good value, but fairly high priced for "What it is", meaning, Great I would reserve for it being at least a few hundred dollars less or so.

Being someone that can DIY, and has an Electrical Engineering background etc, I simply do not "See" a lot of expensive stuff in that half empty box to really justify the price (completely)

I am that too, (Someone who can DIY, is an electrical engineer) and honestly I disagree. I don't have Purifi but I diy'd myself a pair of NC500 monoblocs and I know which price the Purifi components and Power supply go for, and quite honestly, all taken into account, me doing it myself, compared to already built solutions like this, the saving was very minor if any, took a lot more time than I tought, had to settle for chassis nowhere near as nice as that, etc. I find the pricing of what I see there quite reasonable.

 

[Vict0r]

I am that too, (Someone who can DIY, is an electrical engineer) and honestly I disagree. I don't have Purifi but I diy'd myself a pair of NC500 monoblocs and I know which price the Purifi components and Power supply go for, and quite honestly, all taken into account, me doing it myself, compared to already built solutions like this, the saving was very minor if any, took a lot more time than I tought, had to settle for chassis nowhere near as nice as that, etc. I find the pricing of what I see there quite reasonable.

So what would you say is the markup on a build like this?

 

[Interference]

Yup, subjective evaluation and understand the design strength. Especially design part, you can go to hifi show and ask dealers and even the CEO/designers to talk about it. Then you will understand what is their decision in design. They have their own preference and how a setup should be. Even prefer which brand to go with their product or what products are used evaluating their design.

To people who care enough to check what the designers have to say, it is well known that balanced is the recommended interconnection for Hypex and Purifi amps. Yet you came here with random uninformed advice such as "XLR only when you power and amp are far apart more than 3 meters run." So I do not understand why you think it's me who should go and ask around at a hi-fi show

 

[PeteL]

So what would you say is the markup on a build like this?

I would need to know the kind of volume they produce to be able to answer that. I certainly see pretty much no effort to save on electro mechanical components, pretty much a cost no object build. Markup is certainly slimmer than any retail based manufacturers but I believe they sell online only so they can compensate. In all case, one singleperson would want to purchase a case like that and have it silkscreened and routed, well one can't just do it, that would be off the roof. add to that support, waranty and fixed cost to maintain a company. I believe it's a good value.

 

[Ajax]

Thanks Amir, great to finally see a positive review after so many poor ones. Not a reflection on you or ASR of course as you can only review what you receive.

You have opened my eyes (and ears) to many cost effective products and it is now readily apparent that SOTA performance for the front end of a system (Streamer + DAC + Power amp) is available for less than $2k ......... just add speakers.

 

[kongwee]

To people who care enough to check what the designers have to say, it is well known that balanced is the recommended interconnection for Hypex and Purifi amps. Yet you came here with random uninformed advice such as "XLR only when you power and amp are far apart more than 3 meters run."

No harm keep asking. I don't know anything about Hypex and Purifi differential amplifier design. So I speculate on product description. If they don't wanna use differential amplifier design as their marketing hype. I alway assume RCA is better.

3 meter is just a guide. Some 200kg Class A heater you need to put on floor. You need to have longer interconnect to connect from racks. This is you may need to use XLR. Many heaters I know recommend XLR. All based on designer recommendation. Some audiophile used to put pre and source by their sofa side, XLR are highly need. Those different ways to place components you can see all in hifi show. Of course, you can see how people do it in Youtube too.