Yamaha MX-A5200 cooling fan issue

[PENG]

I have one inside the closet somewhere, have to find and will post the temperature. Yeah, I think it's the speaker causing such havoc.

If you look at the phase angle/impedance curve TLSGuy just posted, and if your MKII has similar characteristics, you can do a quick experiment by setting the crossover to 150 Hz or even 125 Hz. You should be able to see the temperature all else being the same (such as the same volume, playing the same music) drop somewhat. Not a solution but just an experiments.

Again a good solution is to grab a Hypex amp, they are cheap in NA but may cost a little more in Europe.
VTV AMPLIFIER Stereo Hypex NC502MP NCore Amplifier 500WX2 | VTV Amplifier
VTV AMPLIFIER Stereo Hypex NC502MP NCore Amplifier 500WX2 | VTV Amplifier

Buchardt also sells Hypex amps, but only integrated amps unfortunately.

The easiest "fix" is to back off your volume setting by 3 dB, that's to turn it down 6 clicks. If you are willing to that, your amp will run cooler for sure and the risk of damage overtime will be much reduced. If you turn it down even a little lower, and use the 8 ohm setting, you should notice improvement in sound quality.

That brings up the following questions:

1) What is your volume setting typically speaking?
2) Do you always have Audyssey on?
4) Do you always have Dynamic EQ on.
5) What is your crossover setting?

 

[TLS Guy]

Keep in mind he has the MKII, that could be worse, but I couldn't find any measurements for those.

Well, according to the company blurb, the upgrade was to use high end caps and resistors, of the Audiophool variety. I suspect it is the same speaker.

The measurements by the way are far from outstanding and nothing to brag about as the FRs are not very good.

Recently I remeasured some small bookshelf speakers I designed and built for $27 each in 1991. The files at the bottom show FR on axis, 10 degrees and 90 degrees off axis. The impedance drops briefly to 5 ohms at 2K and most of the time between six and eight ohms with a tuning peak at 11 ohms. Phase angle is never more than 30 degrees negative. I put in a filter at 300 Hz, as I could not be bothered to position the speaker to get LF measurements, which in any event are not highly reliable below 300 Hz.

The point is the mid band response is really flat and a very easy load. These birchardt speakers are not tower speakers for Heaven's sake, and with all the hype should have a spectacular mid band response. I just don't understand why it is so hard to purchase accurate speakers.

 

[aislam]

If you look at the phase angle/impedance curve TLSGuy just posted, and if your MKII has similar characteristics, you can do a quick experiment by setting the crossover to 150 Hz or even 125 Hz. You should be able to see the temperature all else being the same (such as the same volume, playing the same music) drop somewhat. Not a solution but just an experiments.

Again a good solution is to grab a Hypex amp, they are cheap in NA but may cost a little more in Europe.
VTV AMPLIFIER Stereo Hypex NC502MP NCore Amplifier 500WX2 | VTV Amplifier
VTV AMPLIFIER Stereo Hypex NC502MP NCore Amplifier 500WX2 | VTV Amplifier

Buchardt also sells Hypex amps, but only integrated amps unfortunately.

The easiest "fix" is to back off your volume setting by 3 dB, that's to turn it down 6 clicks. If you are willing to that, your amp will run cooler for sure and the risk of damage overtime will be much reduced. If you turn it down even a little lower, and use the 8 ohm setting, you should notice improvement in sound quality.

That brings up the following questions:

1) What is your volume setting typically speaking?
2) Do you always have Audyssey on?
4) Do you always have Dynamic EQ on.
5) What is your crossover setting?

Thanks for your reply.

Why should I buy Hypex? Is it to get more watt? Would that solve heating issue? Currently my Yamaha has 150w@8 Ohms (more @ 4ohms), and the bridged outpuit will be 150w/ch/8ohms.

I like listening loud but not at ear piercing loud. For this volume I have to turn on Marantz pre-amp's volume at about 70%. I think that's because of low impedance and low sensitivity of Buchardt.

No Audyssey or dynamic EQ.

I am not using any sub, and don't know the cross over point either. But Buchardt's native cross over point is 1800 hz.

 

[TLS Guy]

Thanks for your reply.

Why should I buy Hypex? Is it to get more watt? Would that solve heating issue? Currently my Yamaha has 150w@8 Ohms (more @ 4ohms), and the bridged outpuit will be 150w/ch/8ohms.

I like listening loud but not at ear piercing loud. For this volume I have to turn on Marantz pre-amp's volume at about 70%. I think that's because of low impedance and low sensitivity of Buchardt.

No Audyssey or dynamic EQ.

I am not using any sub, and don't know the cross over point either. But Buchardt's native cross over point is 1800 hz.

Unfortunately it is a jungle out there and you really have to know what you are doing. Mistakes are common, and unfortunately you have made an easily understandable one for the unwary. But you might as well get it straight.

That Yamaha amp is a miserable product and way over priced and here is why.

Its salient specs are that: -

1). It is rated 230 watts into 6 ohms ONLY 1 channel driven, 190 watts into 8 ohm. That is at 0.9% THD. So those figures are inflated, as it would be less at the appropriate 0.1% THD which the power should be quoted at.

2).Power drops to 170 watts at again 0.9% THD. So the miserable power supply is already stressed driving 2 channels let alone 11! In addition no four ohm rating is quoted at all. Only 8 ohm ratings are quoted with more than 1 channel driven.

3). They put a four ohm switch on as they new darn well they would have excess warranty claims if they did not, as the unit is clearly current limited. I suspect because the power supply is totally inadequate.

4). Bridged mode into 8 ohms only increases power to 200 watts up from 170 watts. Again this is confirmative evidence this unit is under designed in a major way.

These specs are very bad and litter this product with red flags.

Unfortunately you have speakers that are four ohm with adverse phase angles. That is why your amp is heating, because in reality it is under powered to drive your speakers, as the specs scream of a unit current limited. Heat tends to kill, and all around I would expect a short life for that unit if pushed hard.

A sub would help, but dumping that power amp and getting something more appropriate to drive your speakers would be the best solution. Alternatively you could get speakers that are an easier load.

I can't imagine how that unit would deal with 11 speakers, especially if four ohm. Most speakers these days are in fact four ohm, however hard the manufacturers try to obfuscate that fact.

So that is why PENG suggested more appropriate amplification and I agree.

 

[PENG]

Thanks for your reply.

Why should I buy Hypex? Is it to get more watt? Would that solve heating issue? Currently my Yamaha has 150w@8 Ohms (more @ 4ohms), and the bridged outpuit will be 150w/ch/8ohms.

I like listening loud but not at ear piercing loud. For this volume I have to turn on Marantz pre-amp's volume at about 70%. I think that's because of low impedance and low sensitivity of Buchardt.

No Audyssey or dynamic EQ.

I am not using any sub, and don't know the cross over point either. But Buchardt's native cross over point is 1800 hz.

Because those amps are very good for 4 ohm speakers and will run cool. I think that is one reason why Buchrdt's only amps are based on the Hypex modules. Your Yamaha amps are not rated for the truely 4 ohm nominal speakers such as yours on continuous basis if you listen to near reference level from more than 10 ft away.

 

[NMG]

Did you mention to Yamaha and/or your dealer that the fans engage for a couple of seconds when you first turn the unit on?

I’ll suggest it again, but that sounds like something is wrong with the amp to me. Mine doesn’t do that on start up and I’ve never read any reports of that happening. I don’t even recall reading any reports of the fans engaging with use, even with the bench tests that Gene put it through when they did the review on this site.

It could very well be that your speakers would benefit from different amplification, but before going down that road I would try and confirm that your current amp is operating properly. Does your dealer have another one they can loan you or can you take yours in to have them test it so they can observe what you’re describing?

 

[aislam]

Did you mention to Yamaha and/or your dealer that the fans engage for a couple of seconds when you first turn the unit on?

I’ll suggest it again, but that sounds like something is wrong with the amp to me. Mine doesn’t do that on start up and I’ve never read any reports of that happening. I don’t even recall reading any reports of the fans engaging with use, even with the bench tests that Gene put it through when they did the review on this site.

It could very well be that your speakers would benefit from different amplification, but before going down that road I would try and confirm that your current amp is operating properly. Does your dealer have another one they can loan you or can you take yours in to have them test it so they can observe what you’re describing?

I did write to Yamaha (both USA and UK), and they said that heating up is not abnormal, and asked to test with a 8 ohms speaker to see the difference.

For the fan, they said it won't turn on untill it reaches max temp, but no words about fan turning on briefly when power button is pushed. I guess that is not that abnormal to count.

After reading/watching many things over last 24 hours, I guess the amp is okay. It is sounding great with the Buchardt, very neutral tone and great dynamics. No distortion, clipping at fairly high volume.

I am trying to get a 8 ohm speaker to test the temperature limit. Will post the update.

By the way, what speaker are you using? I remember you said your unit is always warm but never uncomfortably hot.

 

[aislam]

Did you mention to Yamaha and/or your dealer that the fans engage for a couple of seconds when you first turn the unit on?

I’ll suggest it again, but that sounds like something is wrong with the amp to me. Mine doesn’t do that on start up and I’ve never read any reports of that happening. I don’t even recall reading any reports of the fans engaging with use, even with the bench tests that Gene put it through when they did the review on this site.

It could very well be that your speakers would benefit from different amplification, but before going down that road I would try and confirm that your current amp is operating properly. Does your dealer have another one they can loan you or can you take yours in to have them test it so they can observe what you’re describing?

What is your current setup with MX A5200? Pre-pro, speakers, crossover point for sub...?

 

[NMG]

Hi aislam,

I’m running a 5.2.1 system with B&W speakers. Overall, it’s probably a pretty easy load to be honest. My main speakers would be the most difficult to drive (703s) and here is some info I found from a review online about them:

“The B&W 703's ported enclosure is tuned to approximately 32Hz, and its minimum impedance is 2.8ohms at 100Hz. The impedance remains below 4ohms from about 79Hz to 400Hz—a region of the frequency spectrum that is dense with fundamentals and requires more of an amplifier, over time, than even the deep bass (which makes huge but less constant demands). I would judge this speaker to be moderately difficult to drive. For that reason, I would conservatively rate its nominal impedance at 4ohms. The 703's sensitivity measured about 88dB/2.83V/m.”

I’m using an Anthem MRX-720 as my processor and have everything crossed over at 80hz when listening to music with my sub (2.1) or watching movies with the full 5.2.1 setup. I’m also taking advantage of the bridged channels for the mains. Like I said, the amp will get warm but nowhere close to alarmingly so. I’ve never batted an eye at it. If I’m listening to 2 channel full range with no sub, it will get slightly warmer. But again, it’s all very much in the realm of what I’d consider to be normal.

My room is about 12x22 with 8 foot ceilings and I sit 11 feet away from my main speakers. Dynamics and overall performance are impressive. The amp has no issues cleanly driving my system to levels beyond what I find comfortable.

 

[lovinthehd]

You mentioned bridging, are you currently bridging ?

 

[NMG]

You mentioned bridging, are you currently bridging ?

That’s a good point. I double checked the owners manual and it says that speakers should be 8 ohm if using the bridged channels.

 

[lovinthehd]

That’s a good point. I double checked the owners manual and it says that speakers should be 8 ohm if using the bridged channels.

Yeah if you were bridging I'd say don't do that with that amp for your speakers. Thought I might have hit upon the heat source!