That is just signal to noise ratio. That is less interesting than the rest of the stuff I measure.@amirm
Would you consider this to be a good spec for a power amp?
"Signal/noise ratio: 85dB ref. 2.83V RMS (1W at 8 ohms) "
Oh, not good. I happen to have the FXAudio. I use it as a TV setup with a DAC and a sub over high level outputs. I still prefer it over a class A/B amp it replaced (including in terms of convenience), and much prefer that setup to the AV receiver frankenstein I had briefly. I have been wowed by the sound sometimes, not always. Based on some reviews of it, I expected a little better maybe? Given the small cost, it's still ok. Though I'm surprised FXAudio and Topping aren't able to do better in terms of those bare-bones class D units, given their track records with other devices (FXAudio's 802 FDA and Topping's DACs).
Anyhow, that setup was going to be used to power a Stax energizer, and be replaced for TV duties, for family members' convenience, by a FDA such as the SMSL AD18. Maybe I should wait until it is tested here now.
That's pretty much my view, A DAC doesn't have to drive difficult loads with strange impedance characteristics at high levels, the output load for a DAC is pretty benign. Furthermore, the performance of a DAC is largely determined by the silicon and the board layout, and it's hard to get seriously poor performance, although some 'boutique' manufacturers have made heroic efforts in that direction.Anyway, very interesting and much needed stuff. My guess is that no amp will measure even close to any well designed DAC. But depending on use many may be quite good for their intended purpose...and also that there may be little correlation between price and results.
Thanks for the nice perspective. I think we are all learning together. And filling a vacuum in publishing.So when I look at the current lack of measurement standards...I think Amir's tests will provide much needed perspective.
Well, it is possible for amps to approach the measured performance of a decent DAC if the designers decide that this is a goal. For a couple specific examples:That's pretty much my view, A DAC doesn't have to drive difficult loads with strange impedance characteristics at high levels, the output load for a DAC is pretty benign. Furthermore, the performance of a DAC is largely determined by the silicon and the board layout, and it's hard to get seriously poor performance, although some 'boutique' manufacturers have made heroic efforts in that direction.
Power amplifiers became transparent by the late 1970s or early 1980s, since then the emphasis has been on higher powers, lower cost and greater efficiency, not necessarily in the same product. A power amp from, say, 1985, if in decent condition, will still be as audibly competent as the best of today's equipment. Anything from Hafler, Quad, Musical Fidelity, Krell etc etc etc haven't been improved on sonically since then.
S
I can but I am snake bit right now having bought a bunch of amps which I am stuck with currently.Hi Amir, maybe one day you can measure the Emotiva A-100 speaker amp which costs $229
I actually just ordered a BasX A-100 yesterday - a stopgap while I decide whether I'm multi-amping and how much I have to spend. I'm not sure of the protocol of sending something to you for measurement, but it's definitely possible. I also have a Dayton APA-150 which is in the same category - cheap (even cheaper than the Emotiva) AB amp with passive volume control which might make for an interesting comparison.I can but I am snake bit right now having bought a bunch of amps which I am stuck with currently.
To check how much distortion YOU can hear read this article and get a copy of the Stereophile Test CD 2 tracks 21-23 (2nd, 3rd, 7th harmonic distortion @ 500hz).....
Interesting about Amir and hi res audio......
An update to my earlier reaction to this past week's review of the FXAudio FX502S Pro, as I've had a little time today to compare it back to the amp it replaced, a Teac A-H300 mkIII from about 10 years ago. Given the review, I had to go back and compare.
Please bear with me. I know what ASR represents, but I have no experience in serious audio, or technical expertise, to speak of, and won't pretend I have, so what follows will inevitably seem unrigorous and impressionistic.
Well, there was no contest. Is the FXAudio truly high fidelity? Most likely not. But it had more details, better definition, better instrument separation, more depth and width to the soundstage. At times it really was a 3D soundscape. The Teac doesn't give me that, at least never to the same degree. Sure, there are imperfections, in timbres and the fact that the sound is somewhat thinner, but part of that may improve when I change the modest JBL Control 1s I'm still using (I've haven't gotten around to upgrade that part of my rig yet). Another thing I should mention is I don't typically listen very loud.
Yes, if you can live with weak bass and don’t mind not to have that “hi-fi” sound, there is no better amp that I have listened to for the money.I bought two TP 60. I completely agree on the sound quality of the middle range.
I think that it is the best product for those who like the atmosphere of the old analog amp.
But to me I sold it because I was dissatisfied that the range of low end and high end did not grow.
Especially weakness of bass could not bear.
Naim is a product of my yearning.
The FX502SPro. It look good to use with 4ohm 30watt speaker right.? How about 8ohm 30watt?The FX502SPro falls way short of its 70 watt spec and produces just 37 watts before clipping. The Topping TP60 does much better, producing 60 watts prior to clipping at 0.03%. If I allow higher distortion figures, it can inch up to its spec.