Review and Measurements of Behringer A500 Amplifier

[March Audio]

Sorry, I understood you were just looking at a waveform and not a residual, however all this is visible in an fft.

Distinguishing and identifying the cause of a problem is a useful benefit in looking at the residual, however for what we are doing here it's not that relevant. Seeing SINAD and fft tells us what we need to know for review purposes.

In the case of this amp - yuck

 

[amirm]

And at what random output level is it today, Amir?

You seem to now be testing at 5.228W (or is that the wrong symbol you picked) for SINAD/THD+N when the other day it was 5.0V (6.25W). What will it be tomorrow?

Self clearly has picked full power at the bottom of the THD curve, just before the knee. Every power below it and above it will be a hell of a lot worse won't it?

Unless you have a consistent number (1W@8ohms is the standard and full rated power) none of these 'tests' can be compared against each other. This is the same issue I keep raising and you keep ignoring when comparing SINADs of D/As with wildly differing output levels. You can't compare in a simple ranking based on the number.

Level the playing field.

I am staying consistent with my measurements at 5 watts @ 4 ohm. 1 watt numbers may be industry norm but doesn't represent any kind of useful listening level. And at any rate would allow noise to have higher contributions than my level at 5 watts.

 

[Sal1950]

I am on the hunt for some and one good candidate should be coming in a month or so.

I'd just like to see a Benchmark AHB2

+1
Thought you got on pretty good terms with John Siau, maybe a loaner? Just thinkin

 

[March Audio]

How hard can it be to make a power amplifier with a SINAD of > 80 dB?

Not that difficult.

Hypex ncore are well over 100dB sinad

 

[March Audio]

I am staying consistent with my measurements at 5 watts @ 4 ohm. 1 watt numbers may be industry norm but doesn't represent any kind of useful listening level. And at any rate would allow noise to have higher contributions than my level at 5 watts.

I agree 5 w is a more realistic listening level, in the 90 to 100 dB range with a typical speaker pair

 

[amirm]

Thought you got on pretty good terms with John Siau, maybe a loaner? Just thinkin

I have a chip to cash on their headphone amplifier. I am going to get that first and after that, maybe request the power amp.

 

[Blumlein 88]

Would be good to see the cheaper Crown amps for comparison. I suspect they'll perform poorly across the whole width of the audio band.

#2 for cheap would be some recent AVR's with good power (50-80 wpc). Maybe economies of scale actually buy better amp performance for cheap.
If you wish to bother Amir, some of those can often be had for peanuts on the local craiglist.

It's also possible with modern desire to be cheap and a lack of enforcing FTC regs, there are no good cheap amps out there. Certainly requires more to do this than with DACs and other line level gear.

 

[March Audio]

How hard can it be to make a power amplifier with a SINAD of > 80 dB?

Hypex ncore nc400

 

[amirm]

#2 for cheap would be some recent AVR's with good power (50-80 wpc). Maybe economies of scale actually buy better amp performance for cheap.
If you wish to bother Amir, some of those can often be had for peanuts on the local craiglist.

I don't mind buying a new one but can't figure out which. I looked at a few manufacturer sites and none have any useful distortion specs.

You guys want to research and suggests something below $500?

 

[Blumlein 88]

I don't mind buying a new one but can't figure out which. I looked at a few manufacturer sites and none have any useful distortion specs.

You guys want to research and suggests something below $500?

Okay maybe a bad suggestion on my part.

Just one example. I looked at a few Marantz avr's in the $400-600 Amazon price range. Claimed specs by Marantz are typically .05% to .08% distortion at rated power over 20-20khz with 2 of 7 channels driven into 8 ohm loads. Which is in the ballpark of the results with this Behringer. I Found additional specs for a couple of them which show 1% distortion into 6 ohms, and usually the power claim is the same as 8 ohms. So that makes me think these are not good cheap power amps. So probably not worth the time to test. Oh and these are 50 to 70 wpc.

Looked at the Marantz 2 channel power amps which cost between $800 and $1100. They show the same specs only with 140 to 170 wpc. All of such gear by them claims the use of HDAM amp modules which are class AB not switching amps. So looks like such amps aren't a bargain for great performance either. And these along with the AVRs aren't rated for use with less than 6 ohm loads.

 

[restorer-john]

You'll need to go back to the 1980s and early 1990s for decent specifications on preamplifiers/power amplifiers and integrated amplifiers. Even at the time I was selling audio in the early 90s, performance had well and truly plateaued, the Japanese economy had crashed and the almighty R&D budgets of the big players had all but vanished.

All the truly magnificent statement products were sold off, never to be replaced. Even now, after all those years, the few remaining manufacturers that haven't been swallowed up are re-issuing supposed 'TOTL' stuff I wouldn't put in my loungeroom.

If you want THD numbers down at 0.004% or less and S/N in power amps of >120dB there are a whole slew of options. There's probably a dozen high powered amplifiers/power amps sitting in my room right now with those sort of numbers or better.

It frustrates me to see endless crappy little piss-ant boxes of what is essentially disposable Chinese rubbish, when we have literally tens of thousands of infinitely superior pieces of real high fidelity equipment to choose from on the 2nd hand market.

 

[Blumlein 88]

Just looked at amps in the Stereophile recommended components. A far larger number of amps listed in class A and class A tubed than in class B. Most listings are over $10k, and probably most are over $50k. Several well above $100k. They don't list any in class C or D. I think this is a snapshot of what is wrong with the high end of the market. They did have some well rated listings between $2k and $3k.

I agree there are plenty of 2nd hand very capable amplifiers. But that isn't as helpful for those in the market for a new amp. The good advice is buy amps second hand. Buy DACs, and speakers at least closer to new.

 

[JJB70]

In their 80'sand early 90's pomp the Japanese were making equipment engineered to standards that frankly embarrassed just about everything else yet bizarrely very few audiophiles were willing to accept that. Even the entry level stuff was superbly made however magazines and audiophiles preferred to was lyrical about mega expensive gear with build quality that might have been OK for a DIY project made in a garden shed.
Out of interest I would love to see a few articles and posts on some of that classic gear.

 

[Wombat]

You'll need to go back to the 1980s and early 1990s for decent specifications on preamplifiers/power amplifiers and integrated amplifiers. Even at the time I was selling audio in the early 90s, performance had well and truly plateaued, the Japanese economy had crashed and the almighty R&D budgets of the big players had all but vanished.

All the truly magnificent statement products were sold off, never to be replaced. Even now, after all those years, the few remaining manufacturers that haven't been swallowed up are re-issuing supposed 'TOTL' stuff I wouldn't put in my loungeroom.

If you want THD numbers down at 0.004% or less and S/N in power amps of >120dB there are a whole slew of options. There's probably a dozen high powered amplifiers/power amps sitting in my room right now with those sort of numbers or better.

It frustrates me to see endless crappy little piss-ant boxes of what is essentially disposable Chinese rubbish, when we have literally tens of thousands of infinitely superior pieces of real high fidelity equipment to choose from on the 2nd hand market.

Those old electrolytic condensors(capacitors) and service costs are a turn-off for the average consumer. Even I gave up when commissioning my new speaker build and had a Sony TA-1120 smoke-out and the Sony TA-4650 come down with a serious intermittent volume control malfunction.

Nothing wrong with the speakers, just the old amps. I am past most DIY repairs.

I spat the dummy and purchased a new NAD integrated amp and a new Yamaha Pro amp for my active 2-way system. Good enough for these old ears and no hassle.

 

[restorer-john]

Those old electrolytic condensors(capacitors) and service costs are a turn-off for the average consumer.

Yes, true. But here on ASR we have a bunch of EEs, technicians and electronic hobbyists. From my perspective, I've been inside this stuff for 40+ years and there's nothing that's hard anymore, except my eyesight closeup is starting to deteriorate. (more magnifiers!)

I tell you what, it's almost Christmas, you send me the old Sony 4650 and I'll send you a big plate amp for your slugwoofer. Deal?

Out of interest I would love to see a few articles and posts on some of that classic gear.

I've actually decided to do a bunch of posts here on ASR, complete with specs, internal views, discussion of the design/topolgy and traditional reviews and testing. I'll have to see where Amir wants it to go, because I don't want to derail any more forums/threads with my reviews and rants. Maybe there's a forum he could open up. I have literally hundreds of pieces of classic gear.

My focus was the late 1970s, 1980s and just into the 1990s when this stuff was king. As such, I shake my head at a lot of what is getting reviewed. To me, most of this stuff doesn't deserve to be plugged into a $28K audio analyser.

 

[Wombat]

Yes, true. But here on ASR we have a bunch of EEs, technicians and electronic hobbyists. From my perspective, I've been inside this stuff for 40+ years and there's nothing that's hard anymore, except my eyesight closeup is starting to deteriorate. (more magnifiers!)

I tell you what, you send me the old Sony 4650 and I'll send you a big plate amp for your slugwoofer. Deal?



I've actually decided to do a bunch of posts here on ASR, complete with specs, internal views, discussion of the design/topolgy and traditional reviews and testing. I'll have to see where Amir wants it to go, because I don't want to derail any more forums/threads with my reviews and rants. Maybe there's a forum he could open up. I have literally hundreds of pieces of classic gear.

My focus was the late 1970s, 1980s and just into the 1990s when this stuff was king. As such, I shake my head at a lot of what is getting reviewed. To me, most of this stuff doesn't deserve to be plugged into a $28K audio analyser.

Let me think about the 4650. I don't wish to do a swap but it owes me less than the V-Fets would bring.

If you could organise shipping that would make it easier for me to consider.

 

[Thomas savage]

Yes, true. But here on ASR we have a bunch of EEs, technicians and electronic hobbyists. From my perspective, I've been inside this stuff for 40+ years and there's nothing that's hard anymore, except my eyesight closeup is starting to deteriorate. (more magnifiers!)

I tell you what, you send me the old Sony 4650 and I'll send you a big plate amp for your slugwoofer. Deal?



I've actually decided to do a bunch of posts here on ASR, complete with specs, internal views, discussion of the design/topolgy and traditional reviews and testing. I'll have to see where Amir wants it to go, because I don't want to derail any more forums/threads with my reviews and rants. Maybe there's a forum he could open up. I have literally hundreds of pieces of classic gear.

My focus was the late 1970s, 1980s and just into the 1990s when this stuff was king. As such, I shake my head at a lot of what is getting reviewed. To me, most of this stuff doesn't deserve to be plugged into a $28K audio analyser.

I’d like a classic gear forum , we could realistically measure a lot of it as it’s second hand. Then we would have a great reference vs the newly manufactured stuff.

 

[Blumlein 88]

Yes, true. But here on ASR we have a bunch of EEs, technicians and electronic hobbyists. From my perspective, I've been inside this stuff for 40+ years and there's nothing that's hard anymore, except my eyesight closeup is starting to deteriorate. (more magnifiers!)

I tell you what, it's almost Christmas, you send me the old Sony 4650 and I'll send you a big plate amp for your slugwoofer. Deal?



I've actually decided to do a bunch of posts here on ASR, complete with specs, internal views, discussion of the design/topolgy and traditional reviews and testing. I'll have to see where Amir wants it to go, because I don't want to derail any more forums/threads with my reviews and rants. Maybe there's a forum he could open up. I have literally hundreds of pieces of classic gear.

My focus was the late 1970s, 1980s and just into the 1990s when this stuff was king. As such, I shake my head at a lot of what is getting reviewed. To me, most of this stuff doesn't deserve to be plugged into a $28K audio analyser.

Well you can make a forum suggestion for a classic hardware sub-forum. Then again, I wouldn't mind it mixed into the appropriate existing forums. You could always ask for a master list sticky somewhere so anyone could find those classic threads easily.

 

[Sal1950]

I've actually decided to do a bunch of posts here on ASR, complete with specs, internal views, discussion of the design/topolgy and traditional reviews and testing.

Awesome, looking forward to that John.

 

[JJB70]

Talking of old Japanese gear, some EBay seller in the UK appears to have either found a truck load of 1990's Technics gear or decided to sell a warehouse full of stuff they've been sitting on for a couple of decades. The descriptions are disingenuous verging on outright dishonest and prices high, reading the description implies the gear is the normal end of season or end of run clearance, not stuff that has sat for over 20 years and probably well out of support let alone warranty.