AUDIOPHONICS MPA-S250NC Amp Review

[Foxxy]

You don't "lose" peak power. Both versions have an input sensitivity of 1.66V (2x0.83V for the XLR version), so you can reach peak power easily with anything that can output 2V, even if you feed the XLR one from a single ended source.

Oh really? I always thought XLR->RCA meant a power loss due to the different P-P voltages?

 

[Ropeburn]

Oh really? I always thought XLR->RCA meant a power loss due to the different P-P voltages?

It's a volume difference, that's all. Whether or not you can reach full power is determined by other factors, namely the relation between input sensitivity and actual input voltage. If sensitivity is chosen sensibly in the design like in this case, there isn't a problem at all, and the only practical difference is you having to turn up the source/preamp level a bit more.

 

[Foxxy]

It's a volume difference, that's all. Whether or not you can reach full power is determined by other factors, namely the relation between input sensitivity and actual input voltage. If sensitivity is chosen sensibly in the design like in this case, there isn't a problem at all, and the only practical difference is you having to turn up the source/preamp level a bit more.

Ah, I thought that RCA is fixed 2VPP and XLR 4VPP(+2VP/-2VP) and that input sensitivity of the amps would be tuned to one of these values. And therefore a natively XLR amp would have oto little input voltage for full power receiving a paired RCA signal.

 

[Beave]

Ah, I thought that RCA is fixed 2VPP and XLR 4VPP(+2VP/-2VP) and that input sensitivity of the amps would be tuned to one of these values. And therefore a natively XLR amp would have oto little input voltage for full power receiving a paired RCA signal.

I haven't read through this thread, but if you're referring to line level as RCA, it's typically 2V rms, not 2V peak to peak. And that 2V rms has a tolerance. Even two samples from the same model can be +/- 10% of that 2V, ie, 1.8V rms to 2.2V rms, for example.

 

[GTM]

Good afternoon

Audiophonics purchased a month ago and very satisfied. I hope it lasts for many years.

Thanks to everyone for your comments and testing

Best regards

 

[Acerun]

Good afternoon

Audiophonics purchased a month ago and very satisfied. I hope it lasts for many years.

Thanks to everyone for your comments and testing

Best regards

Purifi is simply fantastic

 

[Karmacoma]

Purifi is simply fantastic

* Hypex

 

[Acerun]

* Hypex

Ha...Hypex too

 

[Wikedlok]

Hi all, received my MPA-S250NC and placed it instead of Emotiva basx a-300, rest of the setup untouched. I noticed the left channel is not in balance with the right, measured it is 5 db down. Being my first class D, is this acceptable or should I return it?

 

[DWPress]

measured it is 5 db down. Being my first class D, is this acceptable or should I return it?

If you are sure you've got it connected correctly and have already swapped cables a 5dB channel difference is unacceptable. Send it back.

 

[AudioSceptic]

Hi all, received my MPA-S250NC and placed it instead of Emotiva basx a-300, rest of the setup untouched. I noticed the left channel is not in balance with the right, measured it is 5 db down. Being my first class D, is this acceptable or should I return it?

I'm surprised that it passed inspection with such an obvious fault. Inform Audiophonics immediately!

 

[Fledermaus]

Bit of channel mismatch doesn't seem that uncommon (though not welcome) more like 3 dB here :

Makes you wonder whether it is a random feature or Audiophonics had a special offer on a slightly defective module batch...
Anyway, 5 dB sounds like a lot. If I were you, I would record objective evidence, including with reversed inputs and outputs, which I would submit to the supplier, requesting a replacement with a compliant unit or a refund.

 

[Wikedlok]

I informed them (did the dac output swap) and they apologized, will replace the unit.
Thanks guys.