Marantz PM6006 or Rotel A11 or Denon PMA-800NE

Heavenlysounds

Standard Member
Couple of years ago we bought a Marantz PM6006 amplifier. To cut a long story very short, I have come to the conclusion that there are reliability issues with this amplifier model. Other people on the Internet are also reporting this amplifier going into circuit protection mode with no seeming cause. One reviewer advises avoiding this model due to reliability issues. At other clients, we have Marantz PM500X models with similar power specs - not a single problem at any of those clients. So it would seem that the 600x range are just not as good as the 500x range. The venue halls are similar size so I doubt that capability is the issue.

The speakers we have got are 2 sets of Q Acoustics Q3030i speakers which are 88dB and 145 Watt. My understanding is that these should be easy to drive speakers. They are 6 ohm though, not 8 ohm. Unfortunately the speakers I wanted to get, which were 8ohm were replaced by a newer line which did not review well. These speakers were highly reviewed.

The Marantz PM6006 was suitable for our needs - when it works! I have looked at replacement amplifiers around the same spec and pricing as the Marantz and found the Rotel A11 and Denon PMA-800NE.

The impression that I get is that the Rotel build quality is by far the best of all three amps. Build quality and reliability is a much bigger consideration than anything else given that this is the third time we have had problems with the Marantz amplifier in the space of about 18 months of actual use. The Marantz seem to use poor quality transistors or whatever it is that keeps blowing when the amplifier goes into circuit protection mode.

However a number of people suggest that the Rotel doesn't like difficult to drive speakers (and I am not sure about our speakers in this context) and seems a bit under powered compared to the Denon. The Denon on the other hand comes across as a bit muddy according to some reviewers.

I like the simple design of the rotel more as the Denon interface looks a bit cluttered. I also don't know that I like the Denon power cord not being removable. So I am more keen on the Rotel than the Denon, but would like to get feedback on the concerns raised about the Rotel and if anyone has tried both amps - what do you think?

We need the amp for assembly type volume, gym, dancing - that sort of thing. So doesn't need to be deafeningly loud like a Disco, but obviously a bit louder than you would have your TV for example.
 

gibbsy

Moderator
The speakers we have got are 2 sets of Q Acoustics Q3030i speakers
Alarm bells are ringing if you're driving two sets of speakers connected to the amp at the same time. Never a good idea. Certainly in the environment you're playing them in, little wonder the Marantz is throwing tantrums. The 6 ohm speakers will have the effect of passing for voltage and make the amp run hotter than if using 8 ohm. If you are indeed running four speakers then your actually driving them at 3 ohms

If you want to drive four speakers then I suggest you look at an AV amp which will be able to drive those speakers efficiently and correctly.

I'm moving this to the Stereo amp board.
 
Last edited:

Heavenlysounds

Standard Member
Yes, I am not so keen on the 6 ohm issue myself. Unfortunately I didn't realise at the time of purchase that they were 6 ohm and I have been kicking myself ever since.

The earlier model amplifier PM5005 model seems to have no issues driving four speakers and has been working for years. We only started seeing problems with the PM6006 model. Also we are using 4 bookshelf speakers, not floor standing speakers.

Regardless, I don't want to buy another Marantz as we have had nothing but problems with it. What I am trying to resolve is what amplifier we should be getting that will actually work.
 

Heavenlysounds

Standard Member
I am busy looking into the 3 ohm issue as this is a good point. However, while I was looking, I came across this topic - which describes exactly the problem we are having with the same amplifier!


The word I was looking for was capacitors not transistors. According to the OP of the linked topic, he has a single pair of speakers and barely moved the volume dial - as he was just using it to connect to a tv. A second person in the linked topic, also reported having the same issue of similar age. I think the reason we notice it sooner is because we use it a lot more. The recommendation there is exactly the same as what I have seen in other posts - i.e. the capacitors are the problem. Somebody on the Internet somewhere said that he thought the capacitors were not good quality on the Marantz.

I do acknowledge the point made about the 3 ohms and I will bear that in mind when replacing the amp, but I don't think this is the cause (although it probably hasn't helped), as I have come across various posts on the Internet reporting this exact same issue.

I will post on that topic as well to get more insight to our problem and see what Marantz had to say about their amplifiers.
 

Helix Hifi

Well-known Member
It has probably nothing do with the Marantz amplifier, when listing to 4 speakers you need to make sure the speakers don’t drop below 8 ohm. This speakers are 6 ohm according to your post.

If you use only one pair, yes the amplifier should have no problems. Depending on the listing room, but I doubt you’ll have any issues.

Edit, yes every manufacturer can have issues. That’s just life. This doesn’t mean every Marantz amplifier is bad. I’ve owned 3-4 Marantz amplifiers, never had any issues.

Have you tried listing to only 2 speakers? Does the amplifier have the same problems then also?
 
Last edited:

gibbsy

Moderator
The QAs have a sensitivity of 88dB. Floorstanding speakers are more often that not are easier to drive than small standmounts. It may not sound a lot but when trying to fill a large space and using an amp as it's not really intended. The A and B speakers posts are meant to be used on separate speakers, perhaps in different rooms where one set or other are being driven.

You are also halving the overall power, so again, for the volume required you are really pushing the amp beyond it's design capabilities.

Have you ever thought about a PA system?
 

Heavenlysounds

Standard Member
To Helix Hifi. You are correct. Marantz have made some very good amplifiers. I never said otherwise as the previous model (PM5005) we have had zero issues. But I do believe that there is a problem with this specific model as there are a number of posts on the Internet reporting the exact same issue. The linked topic for example the OP says - pair of Yamaha 6 Ohm floor standing speakers connected to It. So two speakers at 6 ohm and he has barely used it and exactly the same problem as me. So his problem cannot be an ohm issue as it should be able to drive two 6 ohm speakers particularly at the volume he uses his amp at.

To Gibbsy, I agree that the amplifier and the speakers are not well matched. Unfortunatelywhen I bought the speakers they were not the speakers I had researched and intended to buy. But there we are. I won't be making that mistake again.

I suppose a PA could be an option, but we already have four brand new speakers installed. All we need is an amp that actually works. I will see if I can find one that can drive four 6 ohm speakers or whether I should wire the speakers in series to get them to work on amplifiers that only go as low as 4 ohms.
 

Helix Hifi

Well-known Member
I understand you are not happy. I had problems with Rotel amplifier and came to the conclusion every Rotel amplifier is not quality amplifiers like other brands, of course this is not true.
 

Heavenlysounds

Standard Member
I understand you are not happy. I had problems with Rotel amplifier and came to the conclusion every Rotel amplifier is not quality amplifiers like other brands, of course this is not true.
No, I think Marantz are a good brand. Just not that particular model (as every complaint about this model is exactly the same as my issue) and having being burnt, we are going to try something else as I don't know if the Marantz PM 7007 have the same design flaw - which I am convinced the problem is - a design flaw that is.

The Rotel I looked at was very highly reviewed as excellent build quality. But I am now looking into the 3 ohm issue. If worst came to worst, I could hook the speakers up in series.
 

Flobs

Active Member
The amp imo just isn't designed to do what's being asked of it. 45W into 8 Ohms and only 60W into 4 Ohms being asked to drive 2 pairs of speakers at the same time that according to the manufacturer drop to 4 Ohms (frequence unknown) require an amp of 25W to 75W. The fault Marantz make is putting bornes for 2 sets of speakers (then at the price range it's probably necessary for marketing).
So an AB amp? being asked to work as a D class.
Difficult to find truely 8 Ohm speakers these days, Manufacturers should come to an agreement not to provide the possibilty to drive 2 sets of speakers unless the amp is really efficient (i.e D class?) at this entry level pre-outs would give another option with a power amp but at this sort of price what is expected?
 

Heavenlysounds

Standard Member
To Flobbs, While I think the cause of the amp failure is capacitors not being good quality - based on the fact that so many other people have had exact same issues with this particular model - I do agree with you what you said. The amp is technically under powered for what it is being asked to do.

The problem for many people like me is we are not experts in hi fi and I expect an amp to be able to handle 4 speakers if it is marketed at supporting four speakers. So yes I agree with you. I now understand a lot more about amplifiers and speakers than I did when we first started with this process.

I think I will get the Rotel A11 amp as I like it. I will probably have to wire the speakers we have in serial. But I will use a power meter to measure the wattage, amperage in use to get a better idea of our power usage demands. My understanding is that the sound quality will suffer if we wire the speakers in serial. But as long as they work, I can live with it.
 

robdmarsh

Active Member
The impression that I get is that the Rotel build quality is by far the best of the three
Not so, I've had both amps and the Denon is better built imho than the Rotel. The power cord is not removable but this is not a big deal. The Denon has been super reliable for me, sounds terrific. Specs are similar to Marantz pm6007 but with a little more power. Out of Audiolab 6000a, Rotel a11 Tribute and the Denon I far prefer the sound of the Denon and I have had all three.

Strange quirk about the Rotel, it has an internal DAC that can only be accessed via bluetooth, which on this amplifier is not very good, and not a patch on the SQ of using a dedicated bluetooth receiver like ifi Zen blue.
 

Helix Hifi

Well-known Member
Marantz PM8006 build quality is second to none vs Rotel RA1572MK2!

And the Marantz is “cheaper” but is more expensive now.

Same with Rotel. The Denon you has also expect build quality.

My opinion!
 

Cribbster

Active Member
The Rotel will allow you to connect 2 pairs of speakers but not sure if it is intended to be able to run both sets at the same time. To my ears, I have generally preferred the Rotel sound to the Denon sound: Rotel usually sounds a lot cleaner and clearer, Denon I have usually found a bit muddy and, well, not very inspiring. Although, interestingly, a demo of the A11 Tribute last year left me a bit underwhelmed and I'm not sure it even sounded as good as my vintage Rotel. Not helped by it being directly compared to a couple of significantly more expensive amps, to be fair although I did make sure it was the first of the amps I demo'd.
 

Heavenlysounds

Standard Member
I have already bought the Rotel and it has been delivered to Richer Sounds store. I decided on the Rotel on the basis of what Cribbster said. The Rotel A11 was described by various users as underwhelming, anemic, lean etc which I think is correct. It's not an in your face kind of sound. The focus is more on clarity of sound rather than a more muddy wow factor.

So I am aware of the why the Rotel has mixed views. For a school assembly hall environment the Rotel would actually suit our requirements more than the Denon would. It has more power than the Marantz Pm6006 so hopefully it won't seem underwhelming for our needs.

Cribbster, the Rotel is not designed for 4 speakers in paralle, which is why I will be wiring the speakers up in series to ensure that there is no overload on the impedance. In future, the direction I will go down is to get two larger speakers, rather than four bookshelf speakers so I never have this problem ever again. But we have got four speakers, so this is where we are with that school.

I will update when I have installed the Rotel and tried it out - which should hopefully be next week.
 

Flobs

Active Member
In the long term you should be looking at professional options and mono. Home stereo divices are not designed for halls. Mono because surely your looking for everyone to be hearing the same thing all over the hall. So yes a PA system of some sorts would be the long term goal imo.
Just out of interest how long is the wiring from amp to speakers?
Btw some dealers will push you towards the AV solution I wouldn't go down that path, look into professional options for the future.
 

Helix Hifi

Well-known Member
As mentioned I’d get PA speakers. From my understanding the treble response is tuned differently then hifi speakers, so you can hang the speakers in the ceiling, walls.

I don’t know if the QA speakers we’ll achieve this properly like PA speakers.

From understanding you’ve tried the speakers before, and it worked fine expect less current on the Marantz amplifier.

I don’t know if this has been mentioned, but are you sure the Rotel amplifier is going to sound better...? For school environment I don’t think it well work...
 

Helix Hifi

Well-known Member
Depending if the school is large as class room. I don’t know.

In this cases you need power full speakers like PA, not hifi speakers.
 

Heavenlysounds

Standard Member
When I am looking to put in a new system for any school, I will look into PA systems in more detail. The three main reasons why I am not pursuing that course right now is because:
  1. We already have brand new speakers that are only a year old and I don't want to have to throw those out and we have all identified the primary issue being 4 speakers that are 6ohm being driven by a 4ohm amplifier.

  2. Right now, I don't have the time to research and investigate PA systems which are completely different to the amplifiers we have been using.

  3. All my schools are using amplifiers and speakers in their halls- many of them using systems put in long before I arrived. One of my clients for example is using a Sony amplifier with 2 speakers. The amplifier is about £150 or a little bit more. They have had that for close to ten years with zero issues and they are very happy with the system. So the argument that a PA is required is not necessarily true, which is why I want to research that properly. Apart from this particular client, I have not had a single problem with any amplifier/speaker situation at any school either with reliability, loudness, sound quality or anything like that.
It might make a difference if I point out that these are primary schools, not high schools. So the halls are a bit bigger than a very large home lounge. It's not high school size halls or stadiums. I would agree that amplifiers would not cope with that environment as the hall size is massive compared to primary school halls.

Flobs - the cabling from the back end speakers to amps is probably 30? metres I would guess? I am not good with guessing length. We are not talking 100 metre lengths here.

PA's have been mentioned before in this post and another post (when I was having problems with the amp when we bought it) and next time, I will be reviewing that. But we have already got speakers and I don't have the time to research PA's right right. My other client's seem to be very happy with their amp and speakers, many of them using their systems for yeasr without a single issue. If schools can use a cheap £150 amplifier for nearly 10 years wthout a single issue and concern about volume, sound quality etc, then I doubt we have very demanding environments. These primary school halls are not that big. A high school would be a completely different issue. But I will look into PA's in the future.

The main problem with this particular client is twofold - impedance mismatch between speakers and amps (because using 4 speakers) and based on other complaints, there seems to be concerns about the sensitivity or build quality of PM6006 capacitors. So I will address those two concerns as a starting point.

I will let you all know what we think about the Rotel when I put it in. Just remember - hall size is a bit bigger than a large home lounge. Not a high school size.
 

gasolin

Active Member
To Flobbs, While I think the cause of the amp failure is capacitors not being good quality - based on the fact that so many other people have had exact same issues with this particular model - I do agree with you what you said. The amp is technically under powered for what it is being asked to do.

The problem for many people like me is we are not experts in hi fi and I expect an amp to be able to handle 4 speakers if it is marketed at supporting four speakers. So yes I agree with you. I now understand a lot more about amplifiers and speakers than I did when we first started with this process.

I think I will get the Rotel A11 amp as I like it. I will probably have to wire the speakers we have in serial. But I will use a power meter to measure the wattage, amperage in use to get a better idea of our power usage demands. My understanding is that the sound quality will suffer if we wire the speakers in serial. But as long as they work, I can live with it.

just don't turn it op to high when playing loud or it might get hot


2022-07-02 13_37_01-Rotel CD11_A11 Tribute CD Player_Integrated Amplifer Lab Report _ Hi-Fi Ne...jpg
 

The latest video from AVForums

Prey + Bullet Train reviews, Heat 4K + Event Horizon 4K and all the latest movies and TV news
Subscribe to our YouTube channel

Latest News

Movies Podcast: 8th August 2022
  • By Casimir Harlow
  • Published
AVForums Podcast: 8th August 2022
  • By Phil Hinton
  • Published
Warner Bros Discovery set to combine Discovery+ and HBO Max
  • By Ian Collen
  • Published
What's new on Sky, NOW and Paramount+ UK for September 2022
  • By Andy Bassett
  • Published
Pro-Ject Audio launches X2 B turntable
  • By Ian Collen
  • Published

Full fat HDMI teeshirts

Support AVForums with Patreon

Top Bottom