Advice on upgrading failing power amp

loveanddeath24

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Hi,

Unfortunately my power amp has been playing up for a while now and randomly turns itself off into self protection mode. Sometimes it works fine for a whole film, other times the fan comes on like a helicopter and switches off the amp after about 25 minutes. I replaced the internal fan and also added a AC Infinity cooler that sits directly on top of the amp to draw out any heat, neither made any difference. I took the amp back to where I bought it, they tested it in the store for quite a few hours, but couldn’t detect the issue. However, they only left it on at a low volume, so I imagine that was why the fault wasn’t discovered.

The amp is now out of warranty, so I’m not overly keen to have it repaired after the hassle it has caused me, also it’s an older model now and not worth much I just wondered what the best route to take would be now? Do I buy a better quality replacement such as the Anthem MCA 525, (but not sure if my current pre-amp would be good enough). Or alternatively, buy a second hand pre and power amp that are better quality, but with no guarantee or support if the product fails.

Any advice would be appreciated.

Thanks

Current setup:
Marantz AV7702 Control Amp
Marantz MM7055 AV Power Amp (Causing the problem)
Focal Aria 900 speakers (Front, Centre and Surrounds)
Rel S/3 Sub
Linn Sondek
 
Hi,

Unfortunately my power amp has been playing up for a while now and randomly turns itself off into self protection mode. Sometimes it works fine for a whole film, other times the fan comes on like a helicopter and switches off the amp after about 25 minutes. I replaced the internal fan and also added a AC Infinity cooler that sits directly on top of the amp to draw out any heat, neither made any difference. I took the amp back to where I bought it, they tested it in the store for quite a few hours, but couldn’t detect the issue. However, they only left it on at a low volume, so I imagine that was why the fault wasn’t discovered.

The amp is now out of warranty, so I’m not overly keen to have it repaired after the hassle it has caused me, also it’s an older model now and not worth much I just wondered what the best route to take would be now? Do I buy a better quality replacement such as the Anthem MCA 525, (but not sure if my current pre-amp would be good enough). Or alternatively, buy a second hand pre and power amp that are better quality, but with no guarantee or support if the product fails.

Any advice would be appreciated.

Thanks

Current setup:
Marantz AV7702 Control Amp
Marantz MM7055 AV Power Amp (Causing the problem)
Focal Aria 900 speakers (Front, Centre and Surrounds)
Rel S/3 Sub
Linn Sondek
That is a real pain, Had you lived close to me in Essex I would have taken a look at the unit for you. It is probably a silly fault and should be easy to rectify, once we find the offending item/channel etc.
This amp is obviously not that old as it is still being sold on the Marantz website, I would push the shop who sold it to you, after all it's only just out of warranty and SHOULD be expected to last longer than 3 years, explain to them it's still doing it and has been for quite a while and that you would like them to test properly this time at high volume while you are present. The sales of goods act has now been superseded by the consumer rights act which should still protect you if the item is less than 5 years old. so I would try to push this at them first.
see below;

If you get no joy, most 5 + ch power amps on the market would still work with your controller pre-amp. The Emotiva XPA GEN 3 would probably do the job and is much cheaper than the Anthem as would the Onkyo PA-mc5501 9 ch amp which can be had for £1000 from Audio Visual online with warranty. Onkyo PA-MC5501 9 Channel Power Amplifier - AV Power Amplifiers - AV Online - UK Home Cinema and Hifi Specialists

 
That onkyo is basically the amp sect the section from their flagship avr in a dedicated box. Deisgn wise it doesn't look anything special.

There's emotiva, Iota and tonewinner on the affordable area of the market. They're made by the same company.
 
That onkyo is basically the amp sect the section from their flagship avr in a dedicated box. Deisgn wise it doesn't look anything special.

There's emotiva, Iota and tonewinner on the affordable area of the market. They're made by the same company.

It would be better to state that the amp stages/modules are made by the same company but the casing/internal mounting/psu/connectivity will be unique to each brand.
 
That is a real pain, Had you lived close to me in Essex I would have taken a look at the unit for you. It is probably a silly fault and should be easy to rectify, once we find the offending item/channel etc.
This amp is obviously not that old as it is still being sold on the Marantz website, I would push the shop who sold it to you, after all it's only just out of warranty and SHOULD be expected to last longer than 3 years, explain to them it's still doing it and has been for quite a while and that you would like them to test properly this time at high volume while you are present. The sales of goods act has now been superseded by the consumer rights act which should still protect you if the item is less than 5 years old. so I would try to push this at them first.
see below;

If you get no joy, most 5 + ch power amps on the market would still work with your controller pre-amp. The Emotiva XPA GEN 3 would probably do the job and is much cheaper than the Anthem as would the Onkyo PA-mc5501 9 ch amp which can be had for £1000 from Audio Visual online with warranty. Onkyo PA-MC5501 9 Channel Power Amplifier - AV Power Amplifiers - AV Online - UK Home Cinema and Hifi Specialists

Thanks for the advice. I doubt I'd get any joy going back to the shop as I bought it over 5 years ago, they already mentioned that the warranty had expired when I asked. Last week one of the staff popped in to look at it, but all he did was to look at the connections (which were fine) and said the amp must be faulty and there was nothing he could do. They are encouraging me to replace it with the Anthem, but if the Emotiva or Onkyo are good I wouldn't mind saving some cash as the Anthem has now gone up to £3,899.00. Because of the price gap, surely there must be differences in sound performance and build quality?

Thanks for the offer to have a look at the unit for me if I was close to you, perhaps I could drop it off to you if you are not too far from my location?
 
Not really a fault finding mission visit then was it. I guess it was more of a 'go sell him a new one' than a let's see if we can fix it or at least identify the actual fault. I have a customer in the north west and both being engineers by trade we are actually interested in what is causing the fault in his system. We both know and acknowledge what the solution is, but that doesnt help understand the actual problem or where it originates from.

Ps his solution is also to by an Emotiva!
 
I'm thinking it might now be best to try and get the amp repaired if it's most likely to be a minor issue. I'm not sure if buying a more cost effective amp would bring comparable audio performance to the pricier Anthem without feedback or being able to listen to them myself.

Could someone please advise if it would be best to contact Marantz to do the repairs, or find somewhere else that would be as good but not soo expensive? Any recommendations would be appreciated.
 
Try to find a local electronics engineer if possible, sending back to Marantz would probably be too costly. It is usually in their interest to make you buy a new unit so they tend to bump up their repair prices to put you off. Amplifiers are not particularly complicated and the repair should prove relatively easy for a competent engineer. My guess as it's five years old would be that there maybe just some dried up capacitors that need replacement and if that's the case then less than £200 to repair. Marantz repair could be £500 or more so maybe more sensible to buy a new 5ch amp with a warranty.
It it were me and I decided to buy new I think I would keep your pre-amp and probably just get 3x Crown xls 1502 drivecore amps, 6 channels and 300w per ch to play with for less than £1000, great for cinema duties with stacks of power if you don't mind the look of them all stacked up.
 
Try to find a local electronics engineer if possible, sending back to Marantz would probably be too costly. It is usually in their interest to make you buy a new unit so they tend to bump up their repair prices to put you off. Amplifiers are not particularly complicated and the repair should prove relatively easy for a competent engineer. My guess as it's five years old would be that there maybe just some dried up capacitors that need replacement and if that's the case then less than £200 to repair. Marantz repair could be £500 or more so maybe more sensible to buy a new 5ch amp with a warranty.
It it were me and I decided to buy new I think I would keep your pre-amp and probably just get 3x Crown xls 1502 drivecore amps, 6 channels and 300w per ch to play with for less than £1000, great for cinema duties with stacks of power if you don't mind the look of them all stacked up.
Thanks for the reply.

Any advice where to look for a reliable local electronics engineer? Not having used one before, I wouldn't want to pick one that wasn't reliable, and I imagine there's lots to choose from.

In regards to your recommendation to use the Crown amps, I only require 5 channels as the preamp powers the sub, would that be an issue? Also, how would the Crown compare to the competition when it comes to audio performance (such as the Anthem), I do use it for both cinema and music and it is important for me to get something that is at least as good as what I already have?

Is the Crown easy to setup, as I noticed volume controls for each channel and indicators on the left going from signal to thermal?
 
Thanks for the reply.

Any advice where to look for a reliable local electronics engineer? Not having used one before, I wouldn't want to pick one that wasn't reliable, and I imagine there's lots to choose from.

In regards to your recommendation to use the Crown amps, I only require 5 channels as the preamp powers the sub, would that be an issue? Also, how would the Crown compare to the competition when it comes to audio performance (such as the Anthem), I do use it for both cinema and music and it is important for me to get something that is at least as good as what I already have?

Is the Crown easy to setup, as I noticed volume controls for each channel and indicators on the left going from signal to thermal?

Cheapest non "pro" amps would be Iota or tonewinner

 
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Thanks for that. It's not really about going for the cheapest option. I'm looking for a replacement that would be at least as good as the power amp I currently own. However, if I could find an amp that performs as well as the Anthem 525 at £3.8k for a cheaper cost, then I would certainly be interested.
 
Thanks for that. It's not really about going for the cheapest option. I'm looking for a replacement that would be at least as good as the power amp I currently own. However, if I could find an amp that performs as well as the Anthem 525 at £3.8k for a cheaper cost, then I would certainly be interested.
I think those two will be more powerful than the Onkyo.
 
I think those two will be more powerful than the Onkyo.
Are the ones you recommended an improvement on my current Marantz? Does more power mean a better amp and are they as good as more expensive alternatives?

Does anyone know of a reliable and cost effective place where I can send my amp in the UK to be repaired?
 
Thanks for the reply.

Any advice where to look for a reliable local electronics engineer? Not having used one before, I wouldn't want to pick one that wasn't reliable, and I imagine there's lots to choose from.

In regards to your recommendation to use the Crown amps, I only require 5 channels as the preamp powers the sub, would that be an issue? Also, how would the Crown compare to the competition when it comes to audio performance (such as the Anthem), I do use it for both cinema and music and it is important for me to get something that is at least as good as what I already have?

Is the Crown easy to setup, as I noticed volume controls for each channel and indicators on the left going from signal to thermal?

OK I see on reading your first post again you have an LP12 so you are definitely into high quality sound reproduction for music also, so maybe the crown's are not for you but they are great for cheap high powered HT set up's, the sound Q is pretty reasonable as well.
It is always a difficult situation when when you have a main component like your power amp go down and you're left with just the pre-amp controller.
The thing is, do you repair the power amp and hope it stays reliable (including the 7702 preamp further down the road) or buy a new power amp (still hoping the 7702 stays reliable) or buy a new single amp solution? Sure the Anthem stuff is good but it's hugely expensive.
If you love your 7702 and cannot get the the poweramp repaired reasonably cheaply you could simply buy a brand new 7055 (I can see they are still available for about 1k) to replace the faulty one with and happy days (you could still sell the faulty one, you'd be surprised how many people would still offer a decent amount of cash for it) or go with the Emotiva XPA5 GEN 3 power amp (a pretty decent well built 5ch amp for half the cost of the Anthem £1749)
Another solution is to go with a brand new 1 box amp/receiver like the Denon AVC-X6700 £2300) which isn't exactly too shabby when it comes to music (no xlr's though)
As to repairing your old unit -Unfortunately many independent TV/Video/Audio repair shops have disappeared from our high streets but I'm sure if look hard enough you should be able to find one in your general area.

 
Are the ones you recommended an improvement on my current Marantz? Does more power mean a better amp and are they as good as more expensive alternatives?

Does anyone know of a reliable and cost effective place where I can send my amp in the UK to be repaired?

I don't have any bench tests of those tonewinner/iota or marantz amplifiers. I have not heard any of those. However the design of the Matantz doesn't look great. It's not like identical board design laid out, with large PSU and large amount of capacitors (or smaller amount for each amplifier module) It looks like it has wind tunnel type cooling systemmthat is fan cooled.

The 7702 is a bit out of date lacking latest features but it's still usable for a while Personally I wouldn't go from two box to a avr.

More power doesn't mean it's better sound quality but a amplifier that has more power and larger power supply means it can drive speakers louder and cleaner with less distortion (if you are close to/on the limits of a lower powered amp)


Some places have free quote, I'd see what its going to cost to repair then see if it's worth it.
 
OK I see on reading your first post again you have an LP12 so you are definitely into high quality sound reproduction for music also, so maybe the crown's are not for you but they are great for cheap high powered HT set up's, the sound Q is pretty reasonable as well.
It is always a difficult situation when when you have a main component like your power amp go down and you're left with just the pre-amp controller.
The thing is, do you repair the power amp and hope it stays reliable (including the 7702 preamp further down the road) or buy a new power amp (still hoping the 7702 stays reliable) or buy a new single amp solution? Sure the Anthem stuff is good but it's hugely expensive.
If you love your 7702 and cannot get the the poweramp repaired reasonably cheaply you could simply buy a brand new 7055 (I can see they are still available for about 1k) to replace the faulty one with and happy days (you could still sell the faulty one, you'd be surprised how many people would still offer a decent amount of cash for it) or go with the Emotiva XPA5 GEN 3 power amp (a pretty decent well built 5ch amp for half the cost of the Anthem £1749)
Another solution is to go with a brand new 1 box amp/receiver like the Denon AVC-X6700 £2300) which isn't exactly too shabby when it comes to music (no xlr's though)
As to repairing your old unit -Unfortunately many independent TV/Video/Audio repair shops have disappeared from our high streets but I'm sure if look hard enough you should be able to find one in your general area.


Thanks for the reply.

Yes, I am really struggling in what direction to go in now. Without being able to listen to any of the power amps with my setup makes it a bit of a gamble for me, and having to rely on others opinions can be problematic because there are conflicting comments on forums such as the Emotiva XPA 5, some said it was fine, others said it sounded too bright. The sound of the Marantz is fine, but I don't feel that I need to stick with one brand if another performs better at a similar price point. The cooling is not very good with the Marantz as mentioned above, hence why I think there have been overheating problems with it. I'm wondering it I replaced it with a new 7055, the build quality might be similar to my current amp using the less efficent cooling tunnel approach.

In regards to Anthem, as they on the expensive side, I would assume there's a reason for that with improved audio quality derived from higher quality components? Currently I'm leaning towards the Emotiva unless spending more on the Anthem is worth the extra cash outlay for a better sounding setup.
 
Thanks for the reply.

Yes, I am really struggling in what direction to go in now. Without being able to listen to any of the power amps with my setup makes it a bit of a gamble for me, and having to rely on others opinions can be problematic because there are conflicting comments on forums such as the Emotiva XPA 5, some said it was fine, others said it sounded too bright. The sound of the Marantz is fine, but I don't feel that I need to stick with one brand if another performs better at a similar price point. The cooling is not very good with the Marantz as mentioned above, hence why I think there have been overheating problems with it. I'm wondering it I replaced it with a new 7055, the build quality might be similar to my current amp using the less efficent cooling tunnel approach.

In regards to Anthem, as they on the expensive side, I would assume there's a reason for that with improved audio quality derived from higher quality components? Currently I'm leaning towards the Emotiva unless spending more on the Anthem is worth the extra cash outlay for a better sounding setup.

Marantz AV pres have a high end roll off, so even if a amp is bright that compensates for your Marantz.
 
Marantz AV pres have a high end roll off, so even if a amp is bright that compensates for your Marantz.
Well that sounds like it should be fine then.

In your opinion, is the price of the Anthem worth almost double the expense of the Emotiva? I would rather invest in the amp with the best performance, unless the audible improvements would be marginal?

Would setting up the Emotiva with my current Marantz amp require any changes before using it?

Thanks
 
Well that sounds like it should be fine then.

In your opinion, is the price of the Anthem worth almost double the expense of the Emotiva? I would rather invest in the amp with the best performance, unless the audible improvements would be marginal?

Would setting up the Emotiva with my current Marantz amp require any changes before using it?

Thanks
Well, other than re running the auto calibration with the little mic I can't see any major things you would have to do, it's just a 5 ch amp same as your Marantz, just make sure you connect the Epx-5 the same way as you had the Marantz. I have not personally heard the Emotiva gear but from what I've read it's fairly neutral sounding. That Anthem would have to sound pretty damn amazing for me to lay out that kind of money over the Emotiva. Could you not order the Emotiva and try it out first, most good retailers should allow you to return it if there was a bad match with the Marantz, you may have to pay a restocking fee.
Just one more thing, it WILL sound different to the Marantz when you first power it up so at least allow your ears to become accustomed to the difference and run it for a few days to break in before you decide to return it.
 
As you mentioned that the Emotiva is neutral sounding, I assume that must mean that the Marantz produces a warmer sound which is not as accurate, so it should be better but may take a while to get used to.

Currently I am connecting the amps with good quality RCA cables, would switching to XLR's with the new amp bring improvements?

I will try and find a seller that provides the option for returing it if I am not happy with it. As black friday is closely approaching I might wait to see if there are any special deals to be had. The money saved will go towards a new 4K projector.

Thanks for all the help.
 
As you mentioned that the Emotiva is neutral sounding, I assume that must mean that the Marantz produces a warmer sound which is not as accurate, so it should be better but may take a while to get used to.

Currently I am connecting the amps with good quality RCA cables, would switching to XLR's with the new amp bring improvements?

I will try and find a seller that provides the option for returing it if I am not happy with it. As black friday is closely approaching I might wait to see if there are any special deals to be had. The money saved will go towards a new 4K projector.

Thanks for all the help.
Personally I think the Emotiva should work well with the Marantz, yes the Marantz is a little warm but the end result might actually sound a little forward or toppy, which is great for movies but not so great with music especially if you prefer a warmer sound, you'll just have to rum it for a few hours and see for yourself. I think the XLR connections are generally used for longer runs to cut down on noise so if you don't get much background noise with the phono's then there's not much point going to XLR'S. Perhaps others on here who have experience with XLR's could give you more insight.

As for Black Friday deals, you may get a bit off but I have generally found you get better discounts after xmas in the Jan sales, give someone like richer sounds a call on Black friday and see if they will knock a hundred quid off at least, even if the price is the same as now.
 
Thanks for the info.

Would the Anthem sound a little forward and toppy too, or is it just the Emotivas? I assumed that the power amp (irrelevant of brand) would just replicate what the pre-amp was feeding it. It's a shame there isn't an amp that treats music and films equally.
 
Sorry to resurrect this thread again, but after hearing that the Emotiva might be toppy, I am a bit concerned how it will perform with my Linn Sondek. I saw a few reviews for the Rotel RMB-1555 which mentioned that it was a better perfomer, also it is a bit cheaper than the Emotiva. Would that be a better choice?
 

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