Audiophonics HPA-S400ET Class D Purifi amp

[ririt]

your correct. But I only can repeat what I've read. And the audiophonic buffer does not support the opamps like nord or vtv are using.
But I still think I will go for the audiophonic solution just because they are cheaper with the default opamps. I'm not sure the the very expensive opamps are good value for money. For now for me the audophonic probably has the best value for money.

I have contacted Audiophonics few months ago. In fact, their buffer has been designed to quickly changed opamps if you want. Not every opamp is is compatible but at least the sparkos are. You will have to do it by yourself.

 

[VintageFlanker]

Amir has run comparative tests on op amps and found no substantive differences.

In fact, it even performs worse with custom OPs, actually...

 

[Oklei]

I just wanted to inform you that audiophonics has changed the inner layout of the HPA S400ET slightly. It looks a lot better now than on the first pics in this thread. The power section is now at the complete opposite side of the modules and binding posts.

 

[Fledermaus]

I'm seriously considering the 4-ch variant for an active bi-amp project.
The box is quite packed :

So I'll ask you all experts, any problem with the layout or something ?

 

[Buster Chestnut]

I'm seriously considering the 4-ch variant for an active bi-amp project.
The box is quite packed :

So I'll ask you all experts, any problem with the layout or something ?

why not just get dual mono? What about your speaker design makes you believe you need this amount of power going to your highs?

 

[Fledermaus]

Sure, an AHB2 would be powerful enough for the highs, but the 4-ch Purifi is cheaper
Besides, I'm looking for something really silent, with low-gain or even no-gain option, since my DSP/active filter outputs something like 20 dBu, and it generates hiss with high-gain amps.

 

[Oklei]

Besides, I'm looking for something really silent, with low-gain or even no-gain option, since my DSP/active filter outputs something like 20 dBu, and it generates hiss with high-gain amps.

It has a 'no gain' option but as far as I see it it's not a zero gain input buffer but a total bypass of the input buffer. You'd have to drive the 4.4kOhm input impedance (2.2 single ended) of the eigentakt modules.

 

[VintageFlanker]

We will release a LPA Purifi Mono during August

Hello, @Audiophonics,
I'm about to pull the trigger on your LPA-S400ET.
It would be my fourth custom amp from you. Any update about the Purifi Mono? (Availability, price...) As LPA, I guess it will fit in the same case and will be called LPA-M400ET?

 

[Fledermaus]

@Oklei : With 50 Ohm output impedance on the analog output side I thought it would be fine...
Now I'm wondering, for similar total size and price, would a pair of those half-rack 2-ch units (LPA-S400ET) have any advantage over th 4-ch one ?

 

[Buster Chestnut]

@Oklei : With 50 Ohm output impedance on the analog output side I thought it would be fine...
Now I'm wondering, for similar total size and price, would a pair of those half-rack 2-ch units (LPA-S400ET) have any advantage over th 4-ch one ?

You mean other than being less expensive and not nearly as much overkill as the 4ch?

 

[eduardw]

I'm waiting for the mono version of purifi from audiophonics. 3 mono's would be a bit cheaper then the 4 channel one

 

[Fledermaus]

You mean other than being less expensive and not nearly as much overkill as the 4ch?

2 x 2-ch would be as overkill as, and a bit more expensive than 1 x 4-ch, and maybe more versatile too but with 2 boxes, 2 on/off buttons and 2 power cords instead of 1...

 

[Oklei]

2 x 2-ch would be as overkill as, and a bit more expensive than 1 x 4-ch, and maybe more versatile too but with 2 boxes, 2 on/off buttons and 2 power cords instead of 1...

Apart from the versatility an advantage in going for dual stereo could be better thermal management. But I think this is not a big problem with the ET400 modules. I had problems in the past with NC400 modules shutting down due to overheating. The ET400 are running fairly cool in comparison.

@Oklei : With 50 Ohm output impedance on the analog output side I thought it would be fine...

With 50Ohm you'll just lose a little over 1% of source voltage and are totally fine

 

[Buster Chestnut]

2 x 2-ch would be as overkill as, and a bit more expensive than 1 x 4-ch, and maybe more versatile too but with 2 boxes, 2 on/off buttons and 2 power cords instead of 1...

Oh. Lol. I thought you meant 1 two-channel power amp.
What kind of speakers do you have? I’m still extremely confused why you believe you need to bi-amp.

 

[Fledermaus]

What kind of speakers do you have? I’m still extremely confused why you believe you need to bi-amp.

Oh, please don't be confused, it's for fun !
To set the scene where the action takes place, I'm presently bi-amping my very ordinary 90 dB 3-way 40 yr old DIY speakers with a pair of Kenwood L09-Ms for the lows and a Parasound A23 for the highs - already 20 times as powerful as needed and heating the room like crazy, but I like it !
Yet I'm considering downsizing...
So, to go back to Purifi amps, of course the highs don't need such power, but I don't know of a 25W amp with SOTA performance, balanced inputs, and that would be happy with 8V RMS input voltage - so why not go for the 250W (8 ohm) one ?

 

[Buster Chestnut]

Oh, please don't be confused, it's for fun !
To set the scene where the action takes place, I'm presently bi-amping my very ordinary 90 dB 3-way 40 yr old DIY speakers with a pair of Kenwood L09-Ms for the lows and a Parasound A23 for the highs - already 20 times as powerful as needed and heating the room like crazy, but I like it !
Yet I'm considering downsizing...
So, to go back to Purifi amps, of course the highs don't need such power, but I don't know of a 25W amp with SOTA performance, balanced inputs, and that would be happy with 8V RMS input voltage - so why not go for the 250W (8 ohm) one ?

If you want SOTA performance, you need new speakers

 

[Fledermaus]

You're right !
It's part of the project

 

[Buster Chestnut]

You're right !
It's part of the project

So what’s driving the desire for bi-amping with passive speakers over purchasing active speakers that are already configured that way?

 

[Fledermaus]

Since you're asking : it's more fun, see DIY pros & cons in the latest phono stage review thread... and in case it turns out to be an abject failure, it will still be time to consider selling some vintage stuff and purchase a pair of, say, KH420s.

 

[Buster Chestnut]

Since you're asking : it's more fun, see DIY pros & cons in the latest phono stage review thread... and in case it turns out to be an abject failure, it will still be time to consider selling some vintage stuff and purchase a pair of, say, KH420s.

Why not DIY a pair of active speakers? Personally, I think that would be a more rewarding experience and also net better results, dollar for dollar.