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Audiophonics HPA-S400ET Review (Stereo Amplifier)

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    Votes: 1 0.2%
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As you mentioned it, minidsp and modern DSP can achieve what they do (Fir filters,...) Only in the digital world. Of course it has pros and cons but nowadays the pros really out balance the cons by a lot.

As I said, the room is a very important factor which is often neglected because people simply say ' I can't do anything about it'
Having more subs is not just for having more output and spl but also can reduce stationary waves and have a more consistent response.

I think it is good as you mention to keep the crossover low for a start, you will have a more coherent sound.

As you mention headphones, I own a Neumann ndh30 and a mojo2. I use motphit to eq the set and then I compare to the way I have tuned my hifi equipment.
Strangely enough, it sounds similar which I think is good and in the neutral kind of way.
 
As you mentioned it, minidsp and modern DSP can achieve what they do (Fir filters,...) Only in the digital world. Of course it has pros and cons but nowadays the pros really out balance the cons by a lot.

As I said, the room is a very important factor which is often neglected because people simply say ' I can't do anything about it'
Having more subs is not just for having more output and spl but also can reduce stationary waves and have a more consistent response.

I think it is good as you mention to keep the crossover low for a start, you will have a more coherent sound.

As you mention headphones, I own a Neumann ndh30 and a mojo2. I use motphit to eq the set and then I compare to the way I have tuned my hifi equipment.
Strangely enough, it sounds similar which I think is good and in the neutral kind of way.
I hadn’t heard of the Neumanns! They look comfortable. Have you tried the Beyer 1990s?

I’m trying to find a nice 4 in, 4 out preamp at the level of my atom amp. Another option could be using a second preamp for my subwoofer, and using two volume knobs (could by disastrous). What are your thoughts on that? I contacted audiophonics on it a few days ago, and their response was not too helpful. They told me the dac/dsp should sound fine because “all dacs are dacs” and they didn’t respond about the preamp idea.
 
It is true that if you want to use DSP I think what audiophonics wants to tell you is that in the end it finishes with the DSP dac. I would strongly simplify the chain of components.

Digital streamer/dac - DSP - amp plus sub

I would process the volume with the DSP.

Read the administrator response here


Then you should know that speakers and room will create 70% of the sound. The ncore and purifi amps can be considered as perfect and almost zero influence on the sound (which is good).

What is good if you use the DSP is that you can tune the subwoofer speaker filters very well and you can add some correction - eq.

So you don't need a second preamp, basically you just need to set the subwoofer volume at something which is ok with 80% of the music you listen. Same with the main combo pream-amp.

Then you adjust the volume with dac or DSP. I suggest DSP as it probably does it better.

I personally feed directly the purifi amp with no buffer with the rme, and the rme main cursor is between -20 and -10 dB. No pre amp, no buffer.

With the high end audiophonics buffer, you can choose a gain which suits your needs and get rid of the preamp.

I have never tried beyer. I am afraid of the highs pick... the Neumann is fine and neutral. I had a hedd which was great but very big.
 

This box could be the all in one you need.

And a 400€ ncore would be enough if money is an issue.
Thanks again. The 4 in would be in the context of leading from the dac. But the mini dsp is clearly a more efficient and logical approach. I’ll probably end up going with that.
 
Hey everyone...

I have a question regarding Audiophonics Gain settings, and this review thread seems best suited for that question.

I hope that is OK, since the device I am more interested in is the new LPA-S600NCX with Hypex NCoreX, not the Purifi.
However, the gain logic is the same or very similar, so I hope you guys can help me.

Audiophonics explains the gains in detail for both modules here:

1694433555564.png


I am just wondering if these output voltages listed for the gains apply to XLR or RCA?
It was my understanding that XLR is typically double the voltage of RCA...

So pairing either of these power amps with my Denon AVR-X3600H (that obviously only has RCA outs), which gain setting is better suited?
Can I understand the Vrms values as they are or do I have to double them for an RCA application - forcing me to use the highest gains?
 
The amplifiers have differential inputs, and given the usual way the buffers and inputs are set up, that would be indicating the differential voltage required, not the voltage of a single signal. The input connector in use doesn't directly affect the gain.

If the input is balanced (so via XLR), then to get the 2.07Vrms indicated for 26dB you need 1.03Vrms on each line, so you'd effectively halve the values.

If the input is single-ended (whether via RCA or XLR using an RCA->XLR adapter cable), then you'd need 2.07Vrms on the single line - you use the values as is.

The Denon has 29dB gain on its internal amplifiers. Denons start to distort (a bit) on their external RCAs when they're pushed above around 1.4V, the point at which the unused internal 29dB amplifiers would be overloaded.

The 25dB-32dB settings would all be fine. 25/26dB is a bit low, and 31/32dB is a bit high. The former would have a small amount of distortion if you really turned it up, and the latter would have a bit more noise pick up from the interconnect.
 
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Thank you for the very helpful reply!

If the input is single-ended (whether via RCA or XLR using an RCA->XLR adapter cable), then you'd need 2.07Vrms - you use the values as is.
Great, thanks!

The Denon has 29dB gain on its internal amplifiers.
Where can I find that information?

Denons start to distort (a bit) on their external RCAs when they're pushed above around 1.4V, the point at which the unused internal 29dB amplifiers are would be overloaded.
I sepcifically bought a used X3600, because it does not do that.

From Amir's review:
index.php


The 25dB-32dB settings would all be fine. 25/26dB is a bit low, and 31/32dB is a bit high. The former would have a small amount of distortion if you really turned it up, and the latter would have a bit more noise pick up from the interconnect.
Looking at Amir's measurement, I guess I should aim for >2V to best utilize the highest SINAD, correct?

Sorry for this short derailing of the main discussion everyone, thank you for understanding!
 
Where can I find that information?


I sepcifically bought a used X3600, because it does not do that.

The 29dB thing is a universal receiver convention, thanks to THX; every Denon I've ever seen follows it, and I can't imagine they've changed it for your model - external amps intended to be used for home cinema applications are supposed to have 29dB gain to match. (Not only does that avoid major sensitivity mismatch issues, it also means all your channel trims line up if mixing onboard and external amps. Some other 1ET400A builders do include 29dB in their gain choices.)

If the X3600 has cleared that 1.4V problem, then, yes, it looks like you're good to use the 26dB gains, aiming for up to 2V output. Your trims in the receiver would then be set all 3dB higher than they are now for the same calibration.
 
Hi,
I am interested in this power amplifier to complete my Home Cinema installation with a Denon 8500 HA amplifier, for amplifying the two main column speakers, particularly for audio and video music listening. I am hesitating between this version and the Sparkos version, if any ASR members have information on this optimized version I would be interested in opting for one or the other.
 
I have decided I will take the classic hpa-s400et version, more neutral and fair, will enhance my installation without problem, so far a Nuprime MCX which I will affect on the Surround.
 
Very good power amp, neutral, transparent, balanced registers, the treble is magnificent with lots of translucency, the price/sound quality ratio is great, I am selling my Nuprime which costs 500 euros more. Very good combination of Denon preamp and Triangle speakers with the high end of the dynamic spectrum, few electronics match with these speakers. Thank you for the content of this topic and the analysis made by Amir.
 

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The amplifiers have differential inputs, and given the usual way the buffers and inputs are set up, that would be indicating the differential voltage required, not the voltage of a single signal. The input connector in use doesn't directly affect the gain.

If the input is balanced (so via XLR), then to get the 2.07Vrms indicated for 26dB you need 1.03Vrms on each line, so you'd effectively halve the values.

If the input is single-ended (whether via RCA or XLR using an RCA->XLR adapter cable), then you'd need 2.07Vrms on the single line - you use the values as is.

The Denon has 29dB gain on its internal amplifiers. Denons start to distort (a bit) on their external RCAs when they're pushed above around 1.4V, the point at which the unused internal 29dB amplifiers would be overloaded.

The 25dB-32dB settings would all be fine. 25/26dB is a bit low, and 31/32dB is a bit high. The former would have a small amount of distortion if you really turned it up, and the latter would have a bit more noise pick up from the interconnect.
So what does this mean when connecting my receiver (RCA output) to an amp with XLR inputs. If my receiver is set at a volume so it puts out 2V Through RCA outputs and I use a RCA to XLR cable. Does this mean that I will have effectively 1V going into the XLR input?
 
So what does this mean when connecting my receiver (RCA output) to an amp with XLR inputs. If my receiver is set at a volume so it puts out 2V Through RCA outputs and I use a RCA to XLR cable. Does this mean that I will have effectively 1V going into the XLR input?
With RCA->XLR, the full 2V can be transmitted.
With XLR->RCA, the signal amplitude will be halved.
 
With RCA->XLR, the full 2V can be transmitted.
With XLR->RCA, the signal amplitude will be halved.
Thanks! So the be absolutely sure: this is the case with every hypex, purifi or icepower amp with XLR inputs?
If this is the case, why are companies offering switchable RCA and XLR inputs? Why not just XLR inputs?
 
Thanks! So the be absolutely sure: this is the case with every hypex, purifi or icepower amp with XLR inputs?
If this is the case, why are companies offering switchable RCA and XLR inputs? Why not just XLR inputs?
I'm sure some customers love their boutique RCA cables.
 
Since my two Denons do not have XLR (8500 HA and PMA 110 for Hi Fi, I am in RCA => RCA with the HP-S-400, Denon only put A1H....
My French is impeccable!
 
En tous cas, super ampli cet Audiophonics marche hyper bien avec Denon et pas cher... (en français)
 
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