Audiophonics HPA-S400ET Review (Stereo Amplifier)

[JohnnyNG]

Or is it just an illusion? A microphone can give us the answer

I think that there is really very little difference in the HPA-S400ET performance whether buffered or in bypass.

I think the Pre90 reacts differently to the bypassed load, though. I'm not sure what test/measurement would need to be done to find out.

 

[fadetoblackbs]

I am looking for a 3 channel Amp and found a very similar product to the one tested in this review.
Would you say it is comparable to the 2 channel version of this review?
Any comments or things to consider?
Thanks =)

AUDIOPHONICS HPA-T400ET Power Amplifier Class D 3 Channels Purifi 1ET400A 3x400W 4 Ohm - Audiophonics

We are proud to offer you the AUDIOPHONICS HPA-T400ET, a 3 way class D power amplifier based on three PURIFI 1ET400A modules. This ready-to-use version is aimed at audiophiles who want to equip themselves with a foolproof amplification solution.

www.audiophonics.fr

​

Audiophonics HPA-T400ET Power Amplifier Class D 3 Channels Purifi 1ET400A 3x400W 4 Ohm​

 

[Bob101]

I am looking for a 3 channel Amp and found a very similar product to the one tested in this review.
Would you say it is comparable to the 2 channel version of this review?
Any comments or things to consider?
Thanks =)

AUDIOPHONICS HPA-T400ET Power Amplifier Class D 3 Channels Purifi 1ET400A 3x400W 4 Ohm - Audiophonics

We are proud to offer you the AUDIOPHONICS HPA-T400ET, a 3 way class D power amplifier based on three PURIFI 1ET400A modules. This ready-to-use version is aimed at audiophiles who want to equip themselves with a foolproof amplification solution.

www.audiophonics.fr

​

Audiophonics HPA-T400ET Power Amplifier Class D 3 Channels Purifi 1ET400A 3x400W 4 Ohm​

It has the same PSU as the two channel version (the1200W rated Hypex SMPS1200A400). Audiophonics no doubt will have designed a very good cicuit as buffer board that makes it drive the 3 Purifi modules flawlessly. You will most likely not get the absolute most out of the Purifi modules regarding maximum continous power output. Simply PSU limited: the claimed3x400W equals the 1200W PSU output (though 1500W peak). Nothing in electronics is 100% efficient...
And the resluting penalty in noise/distortion performance is to be determined. Will it be audible? If not pushed to the limit: nope. But certainly measurable...
But: seems like a great, affordable and compact powerful 3 channel amp solution anyhow.

 

[fadetoblackbs]

How do this Audiophonics amps compare to the ones from Nord Acoustics? Looks like they use similar components. Living in Europe I could buy any of them. Still researching and reading =)
Thanks.

 

[Bob101]

How do this Audiophonics amps compare to the ones from Nord Acoustics? Looks like they use similar components. Living in Europe I could buy any of them. Still researching and reading =)
Thanks.

Nord Acoustics makes models using Hypex, Icepower or Purifi modules. They allow you to spec out your amp to a certain degree, and at extra cost. Dual power supplies for your 2 channel amp? No problem, 120£ extra.
Their Hypex based models are (in GB£) very competitively priced and actually offer a lot of ouput Wattage per buck.
I had an Elac dpa-2 power amp on loan for a long time. It used (I think) previous gen Hypex modules (~10% less max output compared to Purifi, a tiny bit more noisy on paper). It also had a fully discrete buffer board powered by a seperate linear PSU. I switched between it and my Audiophonics hpa-s400et many times and found it, personally and subjectively, a little more punchy and somewhat more relaxed in the highs. For the first five minutes of listening. After that I could not tell them apart if my life depended on it. My ears have never been overly critical anyhow. Hypex: certainly OK for my ears...
I have no experience with Icepower products.
If you spec out a Nord Three more or less exactly like the Audiophonics hpa-s400et, today it costs 1.224£, or 1.443€ at the current exchange rate. That is, thanks Brexit, BEFORE import tax, VAT and customs fees. I live in the EU myself. Buying that amp and shipping it from Britain to my Belgian doorstep would cost around 400€ on top of what you pay Nord for the amp. This may vary between different EU countries, but not much. Buying the Audiophonics (from France of course) today would set me back exactly 1.400€.
One thing: the Nord cases do look A LOT better than the Audiophonics IMO. Non-audio folks will actually know it's an (unspecified) audio component! Instead of having to ask what 'that black box' is for

 

[fadetoblackbs]

Thanks Bob.
Just configurated a Nord Three Purifi 1ET400A and did not see those extra fees for shipping to EU Mainland at he checkout.
A roughly comparable amp from Nord vs. Audiophonics costs roughly +250€ but has following features different to the Audiophonics:
• 3 x Hypex SMPS1200A400 Power Supply
• 3 x Nord Buffer Board with OPA1612 Daul Op Amp
Dont know if that differences will be audible to my amateur ears =)

 

[Bob101]

Thanks Bob.
Just configurated a Nord Three Purifi 1ET400A and did not see those extra fees for shipping to EU Mainland at he checkout.
A roughly comparable amp from Nord vs. Audiophonics costs roughly +250€ but has following features different to the Audiophonics:
• 3 x Hypex SMPS1200A400 Power Supply
• 3 x Nord Buffer Board with OPA1612 Daul Op Amp
Dont know if that differences will be audible to my amateur ears =)

The triple power supply is the best solution. That way it's basically three monoblocks in one chassis. I wouldn't worry about EMI noise with multiple SMPS's and class D modules in relative close proximity. The Nord buffer boards I expect to be very comparable to the Audiophonics ones, but I don't know what the gain setting possibilities are on the Nord boards.

But: the extra costs come later, in the form of an invoice from your homenation's friendly customs agency. If you're VERY lucky, sometimes packages can slip trough customs, but you better not count on it! Not paying is not an option, you can not refuse your order once it's been trough customs.

So, on top of what you paid to Nord (including shipping, yes) comes
1. Import duties. Those depend on the kind of goods. Electronics might be exempt, I'm not sure. Count on 4% (for some categories of items this goes up to 17%). On top of which comes
2. VAT (for Belgium: 21%) for the total of (selling price + shipping + import duties). And then
3. A fixed handling fee. These are unpredictable, and depend on the carrier (UPS, Royal Mail,...) and sometimes I suspect just the mood of the actual handler. Generally between 10-20€ for 'normal' size and weight packages.

Don't say you were not warned.

 

[fadetoblackbs]

Thanks Bob.

Taxes etc. might be out of topic here, lets stay on the technical comparisons between both brands =)

Maybe you can check this link and lets continue the conversation over PMs:

European Customs Package No UK VAT and Support, Make It Easy Europe

NO UK VAT FAR LOWER OVERALL PRICE THAN PAYING UK VAT PRIOR TO US LEAVING THE EU (which we don’t agree with) SAVE AROUND 10-15% ON PAYING VAT Get total peace of mind and fixed costs in all EU Countries. We Guarantee that Total Import Duty and ALL fees will not Exceed the cost of … European...

nordacoustics.co.uk

 

[Vhond]

Nord Acoustics makes models using Hypex, Icepower or Purifi modules. They allow you to spec out your amp to a certain degree, and at extra cost. Dual power supplies for your 2 channel amp? No problem, 120£ extra.

Do you coincidentally know why Nord doesn't make Nilai based products?

 

[fadetoblackbs]

Do you coincidentally know why Nord doesn't make Nilai based products?

Do you know other companies that use them? Only found DIY solutions.

 

[Salt]

As far as I know Nilai is distributed for DIY only and (still) not OEM.

 

[Vhond]

But Audiophonics and Apollon also use Nilai (Apollon versus Audiophonics)??

As far as I know Nilai is distributed for DIY only and (still) not OEM.

 

[Salt]

Hypex did the same when introducing N-Core: first DIY (maybe for Beta -Testing?) and then OEM.
Audiophonics is a parts distributor and thus DIY products are available for them.
In the course of time there will be more Nilai products in the market as is with N-Cores.

 

[Vhond]

Hypex did the same when introducing N-Core: first DIY (maybe for Beta -Testing?) and then OEM.
Audiophonics is a parts distributor and thus DIY products are available for them.
In the course of time there will be more Nilai products in the market as is with N-Cores.

What do you mean with 'in the course of time'? Nilai is available since the end of 2022 and I can't imagine Nord Acoustics isn't aware of that? I know a new implementation/design is not developed in a few weeks, but after more than a year?

 

[SonicSleuth]

How can they justifiably charge so much for an empty box, it's gotta be £100 at most. I personally see absolutely no value in it. Can't fix it when it inevitably dies.

 

[Bob101]

How can they justifiably charge so much for an empty box, it's gotta be £100 at most. I personally see absolutely no value in it. Can't fix it when it inevitably dies.

I use ducktape to fix empty boxes

 

[maruko]

Hi, I need some help.

I use a Topping A90 as a preamp connected via XLR to the Audiophonics HPAS400ET.

I use the “M” gain setting on the Topping (+6dB).

Since my DAC is a Topping D90 connected via XLR (4V out) to the A90, so the output voltage to the Audiophonics amp should be 8V.

The Audiophonics gain buffer is set to off, so with this setting the amp has 10V input sensivity.

Since I perceive a loss of low frequencies energy (I feel it like “weakness”) and a predominance of medium-high frequencies with this setting (compared to the configuration with input buffer ON And even more compared to other AB class amplifiers I had such as the Pass X150 and Gamut D200), I wonder if it is only my subjective impression or if indeed, it may depend on the fact that the input impedance of the amplifier with the deactivated buffer is “only” 4k Ohm, instead of the 96K Ohm with the active buffer.

Since the output impedance of the Topping A90 is only 40 Ohms, should be sufficiently low compared to the input impedance of the amplifier with the input buffer set to off (ratio of 1:100, 10 times greater the 1:10 rule of thumb).

My speakers are B&W 702S2 with 87dB sensivity and work at 6 Ohm most of the time with 3 Ohm peaks.

Solved!

I changed my old speaker cable with new Canare 4S11 and now all is ok. Low frequencies are now present and powerful. I don’t feel any lack anymore. Especially if I go up in volume, but also at lower volumes.
So I use M gain on Topping A90 and buffer bypass on the Audiophonics. It is a delightful sound.

I don’t know if the old cable can be the problem, since it was oxidated and unused for a long time. Or maybe its electrical characteristics. Or simply maybe I’m in a good mood or changed something in my room acoustic.

 

[maruko]

But I have another question.

I’m not an expert but I’m curious and since I’m studying and discovering audio science world little by little tanks to this forum, in the Audio Precision literature I read about parameters like “slew rate” or/and “rise time” and, If I got it right, It has to do with dynamics (fast attack and transients) of an amplifier. Right?

I came across it while I was searching the internet about why Spectral amplifications were wide bandwidth. And what was it for. Thus discovering that it would be the only way to reach high levels of slew rate.

So I’m wondering if this is an important measurement still today, also in class D amplifier, since can’t find it in Amir review of this amp.
Any documentation about slew rate of Purifi modules?

 

[Bob101]

But I have another question.

I’m not an expert but I’m curious and since I’m studying and discovering audio science world little by little tanks to this forum, in the Audio Precision literature I read about parameters like “slew rate” or/and “rise time” and, If I got it right, It has to do with dynamics (fast attack and transients) of an amplifier. Right?

I came across it while I was searching the internet about why Spectral amplifications were wide bandwidth. And what was it for. Thus discovering that it would be the only way to reach high levels of slew rate.

So I’m wondering if this is an important measurement still today, also in class D amplifier, since can’t find it in Amir review of this amp.
Any documentation about slew rate of Purifi modules?

'Slew rate' is a characteristic that, by their nature, does not apply to Purifi amps. I think class D amps in general. There is an interview with Bruno Putzeys, the developing engineer behind Purifi, where he specifically adresses this. It has something to do with the bandwith-limited nature of class D. I'll try to track the interview down and post a link if I can.
As I understand and remeber it (please correct when I'm wrong):
There was a period where high amplifier bandwidth (far beyond the audible frequency region) was marketed as a measure of quality. Because of the way slew rates were measured, higher bandwidth amps had a faster slew rate by default. As marketing goes, high bandwidth amplifiers weren't necessarily actually 'faster' where and when it mattered, it just meant the measurements looked more favourable.

 

[TNT]

does not apply to Purifi amps

Of course it "applies" but as the class D amps are not so wideband they will not compare favorly. So its a smart move to say that its "not applicable"... one can very well measure it for the Purifi amp.

Rise time is not interesting at all as long as the power bandwidth is say double hearing range.... 40-50kHz.,,, which it is here...

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