Amp protection lights on

[PWRmx24]

My old faithful Rotel RMB-1095 (5 ch 200w) amp has two saftey protection lights on that won't go out. I turned it on and off a couple of times and disconnected the speaker wires but the lights are still on. The other 3 channels work fine. Any ideas what to do next, other than take it in for service?

 

[TLS Guy]

My old faithful Rotel RMB-1095 (5 ch 200w) amp has two saftey protection lights on that won't go out. I turned it on and off a couple of times and disconnected the speaker wires but the lights are still on. The other 3 channels work fine. Any ideas what to do next, other than take it in for service?

It needs service. Most likely power transistors have failed. I would not use it with protection lights on. Leave it unplugged. The problem is that there are no service guys left. So if you don’t have the test equipment and experience with servicing complex electronics, your options are likely limited.

 

[TLS Guy]

My old faithful Rotel RMB-1095 (5 ch 200w) amp has two saftey protection lights on that won't go out. I turned it on and off a couple of times and disconnected the speaker wires but the lights are still on. The other 3 channels work fine. Any ideas what to do next, other than take it in for service?

Rotel are better organized than most manufacturers. They have eight authorized service center in the You can find them on the Rotel site.

I have a friend who lives nearby that has one of those amps. It also has at least one channel failed and the protection light on. I would service it for him, but I can't lift it. This units weigh 100 lb. I have researched them and the final driver stage is an IC, which was probably a mistake. It is on a heat sink which makes it a tricky repair. This is a common failure with those and it takes down the output transistors pretty much every time. Cost of repair seems to be about $200.00 per channel.

The problem as I see it is that all the channels will likely fail, so to service all channels you are looking at about $1000.00 and up. So it is up to you to consider recycling, selling for parts or repair, or sending to a service center. At 100 lb weight shipping to and fro will be significant unless you are in driving distance of a service center.

 

[Golfx]

Vtv offers 5 channel amps

Five Channel | VTV Amplifier

looks like the weigh 23 lbs and have great bench mesurements

 

[PWRmx24]

TLSGuy,
Thanks for the reply. I think the Maryland Rotel location will work for us. A family member is moving to Washing D.C. and I may be able to get him to take it there this spring.

Do you think it's possible I messed up the RMB-1095 by driving different ohm and wattage rated speakers? I have my old Rotel-1570 processor hooked to the RMB-1095 (5 ch 200 w per at 8 oh) driving the center Polk LSiC (4 ohm 200w) and 2x Bose 301s (8 ohm 75w) and the Rotel RB-1080 (2 ch 200w per at 8 ohm) driving 2x LSi15s (4 ohm 250w). Volume 70 is as high as I've ever gone.....I think.

 

[TLS Guy]

TLSGuy,
Thanks for the reply. I think the Maryland Rotel location will work for us. A family member is moving to Washing D.C. and I may be able to get him to take it there this spring.

Do you think it's possible I messed up the RMB-1095 by driving different ohm and wattage rated speakers? I have my old Rotel-1570 processor hooked to the RMB-1095 (5 ch 200 w per at 8 oh) driving the center Polk LSiC (4 ohm 200w) and 2x Bose 301s (8 ohm 75w) and the Rotel RB-1080 (2 ch 200w per at 8 ohm) driving 2x LSi15s (4 ohm 250w). Volume 70 is as high as I've ever gone.....I think.

No, I don't. The current in the output stage will be higher with lower impedance loads. However, any self respecting power amp with the "pretensions" of that Rotel should be able to handle 4 ohm loads with no problem.

Those amps are known for this issue, largely due to an improper design decision.

I would advise you to get an estimate for repair, as I personally don't think those units are worth investing a lot of money into. They probably will just fix the faulty channels and then a few weeks after you get it back another channel will blow.

My advice after consideration is not to repair that unit and invest in something more reliable.

I don't personally favor putting more then three amps in one chassis and preferably not more than two. However I understand that for the front three in an AV system one chassis is handy. For one thing if you use only two channel amps you are likely to end up with an unused amp channel.

 

[PWRmx24]

Thanks. What's the concern about using the other three channels while two of the protection lights are on?

 

[PENG]

Thanks. What's the concern about using the other three channels while two of the protection lights are on?

If it is outside of warranty, depending on the estimated repair cost it may not be worth doing it. If the other 3 channels are working, it should be safe to keep using it, but if you are still concerned, just email Rotel's tech support.

Volume 70 is as high as I've ever gone.....I think.

That means very little to us, without knowing what is the maximum setting, and your trim level settings, as well as the input source you were using at the time it failed. So, vol 70 could be okay, but could also be too high, dangerously high.

 

[PWRmx24]

TLS Guy wrote: "I don't personally favor putting more then three amps in one chassis and preferably not more than two."

If I go that route I'd look at another used Rotel RB-1080 (I have one already) or RB-991 which seem identical. Paired with my Polk LSi15s, LSiC, and LSi9s. Any thoughts on these two? Or differences betwwen them. Reason being I see these two on used sales.....
Thanks.

 

[everettT]

TLS Guy wrote: "I don't personally favor putting more then three amps in one chassis and preferably not more than two."

If I go that route I'd look at another used Rotel RB-1080 (I have one already) or RB-991 which seem identical. Paired with my Polk LSi15s, LSiC, and LSi9s. Any thoughts on these two? Or differences betwwen them. Reason being I see these two on used sales.....
Thanks.

Those Polks are very hard on amps, I'd personally prefer a Purifi or Hypex NCore X, as they deal very well with low impedence and sharp phase angles, especially throughout the powerband where your speakers are demanding.

 

[PWRmx24]

Thanks for commenting The Hypex NCore X is probably a great amp but I was advised class AB are usually a bit better. I'm not an expert. I've only ever owned Rotel amps. Seems like a good used RB-991, 1080, or 1090 would do just fine. Not sure I'd tell the difference in a "higher end" amp. Not sure.

 

[everettT]

Thanks for commenting The Hypex NCore X is probably a great amp but I was advised class AB are usually a bit better. I'm not an expert. I've only ever owned Rotel amps. Seems like a good used RB-991, 1080, or 1090 would do just fine. Not sure I'd tell the difference in a "higher end" amp. Not sure.

Whoever told you AB is better isn't doesn't have all the information on the two brands I mentioned as they are the most technically sound amps made today, with the Benchmark AHB2 us the closest class AB for large amps.

Note that the amplifiers are load irrelevant and would handle your speakers with ease and many manufacturers use the modules.

NAD M23 Stereo Amplifier Review

The NAD M23 is a 200wpc stereo amplifier utilizing the SOTA Class D Purifi 1ET400A to push the envelope of performance and efficiency. Is this the best amplifier we’ve reviewed in our 25 year history?

www.audioholics.com

Hypex NCx500 Class D Amplifier Review

This is a review and detailed measurements of the Hypex NCx500 NCOREx reference design amplifier. It was sent by the company and kindly assembled by our local expert, @Rick Sykora. As you see the sample is a "monoblock" configuration (one channel) driven by Hypex SMPS1200 switching power...

www.audiosciencereview.com

 

[Golfx]

Thanks for commenting The Hypex NCore X is probably a great amp but I was advised class AB are usually a bit better. I'm not an expert. I've only ever owned Rotel amps. Seems like a good used RB-991, 1080, or 1090 would do just fine. Not sure I'd tell the difference in a "higher end" amp. Not sure.

I agree everettT whoever told you Class AB amps were superior has outdated information—at least a decade’s worth. Class D from hypex and purifi offer the best measurements. Being more efficient they are also much smaller, much lighter and are much cooler running.