My guess, In this particular case would be that Pyle hired an OEM Engineering firm in Japan to make this amp based on their specifications and guidelines. Or they simply purchased the files (Schematics BOM and Gerbers) from them and "designed" around this IP, But Indeed it can mean many things.What is the difference between designed and engineered I wonder? Do they mean designing the case?
Kind a would if it was a normal market yes, but the problem is that Atmos capable "preamps" or processors, are about all more expensive than full fledge AV receivers that includes the amps, so hard to save any money that way and you don't really boost performance neither with these.Seems like this would be a great budget option to pair with an Atmos-capable preamp for driving rear/ceiling speakers, with a higher-quality stereo Hypex or Purifi amp to drive front channels.
Surround pre/pros have always been as- or more-expensive than all-in-one receivers. The problem IMO is that most separates don't actually offer better preamp performance than, for example a Denon X4800H. But the Denons allow you to turn off the internal amps for better performance (and are also limited to 9 powered channels at once) - if you used one in preamp mode connected to a Purifi or Hypex stereo or 3-channel amp for your front stereo/centre channels and this to power your rear side, rear back, and ceiling speakers, you'd get significantly better performance for stereo music and moderately better performance (and additional channels) for surround operation, and when someone eventually makes a pre/pro that actually measures well (or when you need something that supports HDMI 4.0 and Atmos 2.1 or whatever comes next), you have an easy upgrade path without replacing your amps.Kind a would if it was a normal market yes, but the problem is that Atmos capable "preamps" or processors, are about all more expensive than full fledge AV receivers that includes the amps, so hard to save any money that way and you don't really boost performance neither with these.
Sure but can't you simply use Hypex for FL and FR and use the internal amps for the rest? This is not better than the amps Denon use, what do you gain?Surround pre/pros have always been as- or more-expensive than all-in-one amplifiers. The problem IMO is that most separates don't actually offer better preamp performance than, for example a Denon X4800H. But the Denons allow you to turn off the internal amps for better performance (and are also limited to 9 powered channels at once) - if you used one in preamp mode connected to a Purifi or Hypex stereo or 3-channel amp for your front stereo/centre channels and this to power your rear side, rear back, and ceiling speakers, you'd get significantly better performance for stereo music and moderately better performance (and additional channels) for surround operation, and when someone eventually makes a pre/pro that actually measures well (or when you need something that supports HDMI 4.0 and Atmos 2.1 or whatever comes next), you have an easy upgrade path without replacing your amps.
Improved performance on the front channels by having the internal amps disabled, an additional channel, and flexibility for the future, at a negligible cost.Sure but can't you simply use Hypex for FL and FR and use the internal amps for the rest? This is not better than the amps Denon use, what do you gain?
These days Texas Instruments (and others) spec their Class-D chip amplifiers noise output in A-weighted microvolts at idle. Which seems reasonable as it more closely corresponds to audible noise/hiss and discounts less audible AC-line noise (hum) at low levels.@amirm would you consider publishing the average noise figure or the noise spectrum? Often on amplifiers like this noise is more of an issue. You may live with above average distortion on say, a surround channel, but you will not be happy if the surround speakers near to your ear, hiss.
Thanks, just to clarify, are you saying that you can only disable all the amps or none of the amps. Like one power switch for all?Improved performance on the front channels by having the internal amps disabled, an additional channel, and flexibility for the future, at a negligible cost.
My thoughts exactly. Monoprice needs some competition. IIRC they sell 6x 150 for about 1500.Maybe for $ 399 they could design, build and sell a SOTA 2-channel 500 watts amp!
Thank you Amir for a very intriguing review.
Forty years ago many audiophiles were retreating from S/S back to tube amps and preamps. To them S/S in general was "harsh" and "unmusical". (FWIW, I wasn't one of them.) But I've suspected the reason for this trend was that those old S/S amp had quite low THD, like the Pyle, but the harmonics were overwhelmingly 4th order and higher. Tube amps, OTOH, had higher THD but the predominant distortion was 2nd and/or 3rd order. O my technophile friends, here's some truth to dwell upon: 2nd/3rd order harmonics not only sound benign, (to many people), but also mask the unpleasant higher order harmonics.HIGH DISTORTION?????
Seriously sir, forty years ago it would have been highly recommended in the few rags that did measurements (HiFi Choice* being one of them). Sure the 15kHz performance ain't that grand today, but I bet it still beats established audiophool confections costing thousands!!! It appears to have output protection as well!
* One very well known UK brand back then offered distortion at -80dB at 20Hz and 1khz at rated power, reducing to -60dB at 20kHz. IMD (19 + 20kHz) was around at rated output 'in the upper -60's. Obviously tested with different gear, but I'd suggest worse than this eight channel amp and these old relics fetch many hundreds per box even today and due to circuit drift after a couple of thousand hours use, there's an entire after-market for servicing them!!!
Yes, "preamp mode" is an all-or-nothing toggle. Per the Denon product manual:Thanks, just to clarify, are you saying that you can only disable all the amps or none of the amps. Like one power switch for all?
Yes. I looked for that wondering whether bridging to 4 CH operation. Might be in the 300W @8ohms territory. That is some heavy duty jamming on the cheap.What is the load impedance in this measurement? Why is it not stated? Measurement is done at only one resistance value?
That varies a bit with model. The 8500 you can set it for individual channels (as well as the new A1H I assume). Some can set it for 2 of the channels or all.Yes, "preamp mode" is an all-or-nothing toggle. Per the Denon product manual:
"0 Set “Assign Mode” to “Preamplifier” if connecting all channels to the Pre-out connectors using an external amplifier. (v p. 218) This stops operation of the internal power amplifier of this unit, reducing interference in the preamplifier created by the power amplifier"
I'm curious if that will actually improve performance. If you just disable your front channels and are still amplifying 7 rear/surround/atmos channels, one would think you're not going to get the advantages of reduced interference that disabling all internal amplification gives you. But I don't want to claim that's definitely the case without it being tested.That varies a bit with model. The 8500 you can set it for individual channels (as well as the new A1H I assume). Some can set it for 2 of the channels or all.
So you know that for a fact--that most if the HD was fourth order and above? What I remember from the 80s was early 80's thd death of kits and the refining of the behemoths (Phase Linear, ESS, McIntosh, etc) and then the later half getting numbers around 0.00x% while chasing TID. Perhaps coincidentally mass market magazines like Stereo Review died in the late seventies and it was the time of ascendency of Stereophile and TAS which covered a lot of tube gear from Conrad-Johnson znd Audio Research. Stuff which was very attractive, cleanly built and easy on the ears. The tube heads from the fifties were late or never fully accepted transistors as a viable basis for audio amplification even years after all the demons were slayed.Forty years ago many audiophiles were retreating from S/S back to tube amps and preamps. To them S/S in general was "harsh" and "unmusical". (FWIW, I wasn't one of them.) But I've suspected the reason for this trend was that those old S/S amp had quite low THD, like the Pyle, but the harmonics were overwhelmingly 4th order and higher. Tube amps, OTOH, had higher THD but the predominant distortion was 2nd and/or 3rd order. O my technophile friends, here's some truth to dwell upon: 2nd/3rd order harmonics not only sound benign, (to many people), but also mask the unpleasant higher order harmonics.
The Pyle amp is a throwback to S/S of forty years ago. The best contemporary S/S amps have virtually no higher order harmonics or much of any order of harmonics. I'm no advocated for "audiophool confections", my Purifi amp is the best amp I've ever owned.
The difference isn't likely audible in any case, but Amir's testing has shown better results using the pre-amp mode.I'm curious if that will actually improve performance. If you just disable your front channels and are still amplifying 7 rear/surround/atmos channels, one would think you're not going to get the advantages of reduced interference that disabling all internal amplification gives you. But I don't want to claim that's definitely the case without it being tested.