Monolith 8250x 8 Channel Amp

[Verdinut]

Maybe under most listening conditions. However, for a few hundred dollars more one can buy a cleaner amp and a better peace of mind.

I would refer you to post #35 above. We shouldn't have to worry because Monoprice quotes very conservative figures. According to PENG, the tests on the 8250x showed SINAD figures well better than those published by Monoprice, and closer to figures that you would find on the ATI products. You can verify with him.

 

[3db]

I would refer you to post #35 above. We shouldn't have to worry because Monoprice quotes very conservative figures. According to PENG, the tests on the 8250x showed SINAD figures well better than those published by Monoprice, and closer to figures that you would find on the ATI products. You can verify with him.

Thats a good and bad thing. Its good that it performs better than published but its a bad thing because of the missed sales oppertunity based on inaccurate specs making it look worse than it is. I have no respect for marketing.

 

[fmw]

Maybe under most listening conditions. However, for a few hundred dollars more one can buy a cleaner amp and a better peace of mind.

I've never heard a sonic differenece due to peace of mind.

 

[3db]

I've never heard a sonic differenece due to peace of mind.

I guess you missed my point. Try reading it again instead of concentrating on a pithy response.

 

[fmw]

I guess you missed my point. Try reading it again instead of concentrating on a pithy response.

Yes I missed your point. Pithy enough?

 

[3db]

Yes I missed your point. Pithy enough?

Not quite. You're a bright boy. You'll figure it out.

 

[lovinthehd]

Not quite. You're a bright boy. You'll figure it out.

Under what circumstances would one hear that difference in spec particularly?

 

[Kleinst]

Under what circumstances would one hear that difference in spec particularly?

I sure as hell wouldn't most likely. I either like what I hear or I don't. And frankly recently found I thought something was a speaker problem and was a source problem. Good thing I figured that out before buying new speakers. (I thought about it

 

[fmw]

Not quite. You're a bright boy. You'll figure it out.

What would you like me to figure out? My point was that .05 harmonic distortion is inaudible. You suggested that the amplifier wouldn't provide peace of mind. In a pithy way I explained that peace of mind has nothing to do with amplifier performance, which is the topic of the thread. If you have information to the contrary then post it rather than insulting me. I think you take your equipment focus too seriously.

 

[3db]

I was referring to the .5% distortion between 5KHz and 20KHz, not the .05% for the 20Hz to 5KHz spec. Under certain conditions, 0.5% may become audible. For a few hundred dollars more, one can get an amp that measures .05% across the audio bandwidth which is inaudible across all listening conditions. Having it inaudible across all listening conditions is the peace of mind factor, I'm referring too. Turns out that ASR measurement results are better than their published specs so the discussion is moot at this point.

 

[the machine]

I was referring to the .5% distortion between 5KHz and 20KHz, not the .05% for the 20Hz to 5KHz spec. Under certain conditions, 0.5% may become audible. For a few hundred dollars more, one can get an amp that measures .05% across the audio bandwidth which is inaudible across all listening conditions. Having it inaudible across all listening conditions is the peace of mind factor, I'm referring too. Turns out that ASR measurement results are better than their published specs so the discussion is moot at this point.

link to ASR measurements please? I can't seem to find it

 

[everettT]

link to ASR measurements please? I can't seem to find it

There isn't one yet, the referenced numbers where from monoprice with an Audio Precision.

Monolith 8250x 8 Channel Amp

The test data show much lower than 0.5%. The specs did not say 0.5, it says less than.. The specs stipulate: "less than 0.05% between 20 Hz and 5 kHz and 0.5% between frequencies 5 kHz - 20 kHz. We have to figure that they meant less than 0.5% as well for this latter frequency range. Sorry...

forums.audioholics.com

 

[PENG]

link to ASR measurements please? I can't seem to find it

There is no ASR measurements yet for this amp. The measurements I referred to before were Monolith's own measurements that are available on their website, and I pasted the ones that you will likely be interested to see in my post#444.

I wouldn't worry about the 0.5% for the range 5-20 kHz that 3 db mentioned because:

a) Monolith may just be a little more conservative with their published specs vs other manufacturer's.

b) To compare distortion specs, it is not very useful to compare the figure at 1 point, in this case it would be 0.5% at rated output, 20-20 kHz. It would be much more meaningful to look at the curves, such as those I pasted in post#44.

For example, take a look of the following ASR measurements for a Yamaha such as the RX-A1080, I picked Yamaha because 3 db is participating in this thread. Oh, I could have picked the RX-A3080 that ASR also measured but that one was a refurbished one so that likely would raise doubt among fans.

Review and Measurements of Yamaha RX-A1080 AVR | Audio Science Review (ASR) Forum

Below is the one that I always would like to see. You can clearly see that as shown in the 1 kHz test curve, at the 0.5% point, that is -46 dB, this little AVR managed almost 200 W, probably about 190 W, both channels into 4 ohms, that's excellent. If you look at the 20 kHz curve, the output would drop to about 170 W.

So based on this set of curve, you can say that this AVR did not have SOTA performance at lower output level, but was very good at higher output level, relatively speaking such as when compared to a D+M AVR.
Review and Measurements of Yamaha RX-A1080 AVR | Audio Science Review (ASR) Forum

Now compared that with the Denon AVR-X3600H and you can see a very different picture:
Denon AVR-X3600H AV Receiver Review | Audio Science Review (ASR) Forum

If you compared their specs, they are very comparable:
RX-A1080 - 0.06% 20-20 kHz at rated output
AVR-X3600H - 0.08% 20-20 kHz at rated output.

So again, whether the specs say 0.05%, or 0.5% for the full audio band 20-20 kHz, in reality, would depend a lot on the rated output spec. The Monolith could have lowered the distortions spec to 0.05% simply by specifying rated output at say, 300 W instead of 400 W into 4 ohms.

 

[the machine]

@ PENG,

I was just referring to this from 3db

Turns out that ASR measurement results are better than their published specs so the discussion is moot at this point.

He seemed to be saying that ASR measured this amp, which I had never seen, because it doesn't exist.

 

[PENG]

@ PENG,

I was just referring to this from 3db



He seemed to be saying that ASR measured this amp, which I had never seen, because it doesn't exist.

Understood. ASR did measure the ATI amp that is based on the Hypex modules and ATI made the Monololith class AB amps so it is reasonable to assume Monolith's 8250 would be made by ATI as well and further assume the 8250's measured results would be similar. Lots of assumption though, someone needs to send one in to ASR, or hopefully Gene will get one measured here on Audioholics.

ATI AT522NC Stereo Amplifier Review | Audio Science Review (ASR) Forum
It didn't do well at 20 kHz but as Amir noted based on the 0.1% THD point, there isn't much energy at such high frequency so audible concern would be low. Besides, testing at 20 kHz is really moot, because the much higher THD would be due to ultrasonic frequencies anyway, that are not audible. 2nd harmonic of 20 kHz is 40 kHz!! Basically, measuring THD at higher than 10 kHz doesn't really mean much in general. Manufacturers that specify 0.05% THD 20 to 20 kHz don't necessarily tell the whole story as they might have use filters to filter out the ultrasonic harmonic frequencies during their measurements, without telling us the filter's cutoff point.

 

[the machine]

I'm such a noob, but I have to ask. Do I just run a 3.5 from the trigger on my AVM70 to the trigger input on this amp, and then it will power on without me having to manually push the button on the front?

Is there a setting to turn the LED off when the amp is powered on?

 

[PENG]

I'm such a noob, but I have to ask. Do I just run a 3.5 from the trigger on my AVM70 to the trigger input on this amp, and then it will power on without me having to manually push the button on the front?

Yes, according to the manual, the 8250 should come with the trigger cable.

Is there a setting to turn the LED off when the amp is powered on?

I don't think so, the manual does not say there is such an option.