Denon pma-11


Bronze Member
Username: T_bass

North Platte, NE United States

Post Number: 14
Registered: Aug-16
I gave this pre to my son.For an unknown reason he plugged his CD player into the phono jacks. channel doesn't work.
It was always a good pre. Opinions on a fix?
As always.....Thanks.

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 18275
Registered: May-04

More than likely it is simply a matter of age with the pre amp. Old stuff breaks.

Gold Member
Username: Magfan


Post Number: 3376
Registered: Oct-07
amplification is done in 'stages' Add another stage or 2 for a phono section of an amp intended for vinyl reproduction.
Plugging in a HIGH LEVEL source to thet input MIGHT pop the first stage 'input' transistor of the phono section.
This might be, but is probably NOT a proprietary device. IOW, it can be fixed.

A shop will charge for the 'estimate' and probably shred the estimate if you go ahead with the fix. Tell 'em everything and that you only want the phono input stage to be checked. THAT might keep costs down and beeline the tech to the defective part(s).

Trouble in paradise? Jan has a point. OLD stuff fails. If it is more than 15 years old, once fixed, it could fail AGAIN and in some unpredictible and unrelated way to the first failure. Your first instinct might be to blame the shop, but that's not right. If <10years? Should be fixable and go on to another decade or so of reasonable service.

How much is this worth to you? Something like a Parasound P3 is probably available 'used' for 300 or so $$$.
I see one on EPray right this minute for 350$ but know nothing more than that.

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 18276
Registered: May-04

"amplification is done in 'stages' Add another stage or 2 for a phono section of an amp intended for vinyl reproduction.
Plugging in a HIGH LEVEL source to thet input MIGHT pop the first stage 'input' transistor of the phono section.
This might be, but is probably NOT a proprietary device. IOW, it can be fixed."

While that statement is somewhat, partially, not quite really true - phono stages are discrete circuits - that doesn't sound like the correct analysis of the issue.

Unfortunately, T-Bass has left out an important detail. One channel of the amp is non-functional. But, at that point does the channel fail? That is what we do not know from the op.

If the power amp section of the amp has failed, then I would stick with my original post.

I have detailed in several posts how a component should be restored to functioning operation after a long period in storage. It does not include simply plugging the component into a wall outlet and slamming its power supply with a full 120VAC.

I don't remember this specific unit but it appears to have been an integrated amplifier and not solely a pre amp. My recollection of the Denon line says "PMA" designates an integrated amplifier.

So, where has the failure occurred?

It is not an impossibility the CD player's higher output Voltage did overdrive the phono stage, though, as I said, the phono stage is a discrete circuit within the pre amplifier section of this integrated amplifier. It's probably on its own board which would isolate it further from the pre amp functions of the integrated amplifier.

I would somewhat doubt the CD player did any significant and lasting damage to the phono section but, even if it did, that would not affect the rest of the pre amp and power amp functions. It would only affect the phono pre amp.

If the rest of the integrated amp is functioning, buy an outboard phono pre amp if phono inputs are desired. Plug that unit into a high level input on the PMA-11.

Problem solved.

If the power amp is non-functional, then the cause probably has nothing to do with the abuse done to the phono pre amp. Now the cause for the problem is far more likely the way the component was dealt with after being in storage.

This was in storage, right? You don't tell us much, T-Bass.

None the less, this is not a new component. Stuff breaks and old stuff breaks even more frequently. Kinda the logic of limited warranties and time limits on manufacturer's responsibility.

The rest of what leo posted isn't exactly going to help I'm afraid.

No repair shop will only examine a phono section of an integrated amplifier. What would that tell them if the problem with the phono section is actually related to a power supply problem?

And, besides, what's the point of troubleshooting THIS phono pre amp? Buy an outboard unit and forget the crap Denon put in this integrated. It's probably a chip anyway and that chip may not even be available for replacement. Are you really that friggin' interested in saving this specific phono section? If so, have at it but it makes no sense to me.

When you ask a repair shop to take on a job, they are taking on the entire unit and they realize they will be held responsible for the entire unit.

Audio components are not like your car in this respect, you cannot say you only want your tires checked and forget the rest of the vehicle.

The shop can't say, "We only care if the phono section doesn't work next week." Even if they said that, they realize too many customers would be blaming them for screwing up their amplifier if the thing caught on fire within the next year.

You can certainly try leo's ploy but I wouldn't expect you will get very far with that. Besides (again), the estimate cost is fixed for a unit, not by pieces of a unit.

"Yeah, I'm not that hungry, how much will it cost to just take a bite out of that doughnut?"

You don't get half the estimate cost by saying you only want half the component checked out. That would be like going to your barber and saying you'll only pay half the cost because you only want half your hair cut. Things don't work that way.

Most shops simply won't deal with "old" stuff. They do not want to be tied down to a piece of equipment that is likely to break again - soon.

Customers (somewhat rightly) assume that when the shop repaired the phono stage, they were taking responsibility for the entire amp because no shop I am aware of would only fix the phono section if the power amp section also had a problem.

And, if some other part of the amp fails for largely the same reasons of how the unit was brought up to operational Voltage, the shop doesn't want to be fixing the same unit for the next two years for free under their provisional warranty that was intended only to cover their first repair.

Really, would you want a shop to hand you back an integrated amp saying they only fixed the phono section because that's all you were willing to pay for but you should know the power amp still doesn't work?

There are shops which will repair "old" stuff. If you find one, ask for the estimate and expect to be charged the full amount for the entire unit you are asking about. If you proceed with the repair, the estimate cost will be rolled into your final repair bill.

If you have to ship the unit somewhere and pay for shipping both ways, then I'd say you should decide just how good this integrated amp really was when a new component with a warranty can be purchased from, say, NAD for about $379 and it will be a better integrated amp all the way around unless you are concerned about the number of buttons and knobs offered;

Unless you really have your heart set on a certain component or unless you have a written warranty coming with the component, I would avoid buying used gear to replace other broken used gear. You don't know how the other guy dealt with this used component and you have no idea whether it will break in a few weeks like you other old stuff did.

IMO, unless you have some written form of recourse, don't cheap out. Just buy a new integrated amp with a warranty and be done with it.


Gold Member
Username: Magfan


Post Number: 3377
Registered: Oct-07
Jan, they DO speak of 'stages' of amplification. They don't call it a 'phono stage' because horses pull it around.
Phono inputs typically are a stage PRIOR to the first stage of the amp.
You know they are dealing with MV or even UV while a high level input like from a CD player will max out from the 1v to 2v range.
What I said is true. Plugging in a device outputting a full volt into a circuit expecting 10mv max must come as quite a shock, so to speak. The MOST sensitive stage is the FIRST stage and that transistor is most vulnerable to overload.
This comes into play IF the high level inputs continue to work. If the entire channel is dead? I'd look at a fuse before taking it into a shop. I'd also want it all gone over, in that case.

I WOULD like to know how old the preamp is and how long it was in storage. And what other checks you've done. Do OTHER inputs work? Will the CD work thru OTHER inputs? It COULD still be something as stupid as a fuse. One big jolt goes thru the amp and pops the PS fuse for one channel.

BTW, Pass makes a selling point about limited number of stages of amplification. Even my Parasound makes an issue of extra gain (could that be another stage of amplification?) for the iPod input.

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 18278
Registered: May-04

"Jan, they DO speak of 'stages' of amplification."

"They", leo?

Who be "They"?

Isn't that pretty much the same as "A lot of people are saying ... "?

Yes, there are "stages" of amplification. And it depends on the complexity of the amplifier when it comes to how many stages might be employed. Many high end designers such as Pass minimize the number of stages - or devices - the audio signal must pass through before being handed off to the loudspeaker. Doing so places a good deal of strain on design and specification parameters - and associated costs - to ensure high quality signal handling throughout the amplifier. Pretty much why high fidelity equates to high cost.

Most mass market amplifiers have been designed to minimize interactions between components and that makes their concessions to staying sold a part of why they lack the highest level of audio quality.

Since you like Elliott so much, here;

Most transistor (at least) power amplifiers have an input and a driver stage. Tubes can often do with less and chip amps often dispense with most traditional gain stages.

The input stage may deal with splitting the phase of the signal to accommodate a push pull design. Or it may invert phase if the designer is concerned about maintaining absolute electrical phase throughout the circuits. Including any NFB circuit in the design will mean the final output is inverted in phase unless the design re-inverts the signal to maintain absolute phase at the outputs. That's not exactly a stage though, more just a circuit.

The input stage will also typically establish what sort of amplifier the design will be by determination of the feedback type. Or whether the circuit is a Voltage gain stage or a Current gain stage. (Since vacuum tube triodes have a self contained feedback loop and tend to be current source devices, this feature may be eliminated in some designs.)

The driver stage for most power amplifiers generally establishes a sufficient input Voltage level to drive the (next) output stage to full power irregardless the input Voltage from the (average) source.

Driver tubes are often called pre amp tubes inside the power amp and not the pre amp itself. So, often, there will be a few dB of gain applied by low gain factor devices - in a tube product this may be a tube such as a 12AU7 with a gain factor of 17 vs a factor of 100 for a 12AX7.

Quite a few hybrid designs will use a tube such as a 12AU7 in order to say they have a tube sound. There's virtually no gain applied by the tube but passing the signal through the tube gives the marketing department a thrill.

The final stage will be the outputs.

If the circuit is well designed and the designer is expecting a fairly easily determined input signal Voltage and impedance, the design can be simplified. The designer who is hoping to sell a complete system or states the specs required for good component matching has more leeway here.

Impedance mismatches account for many ill chosen systems where individually the same components in another system might sing.

An integrated amplifier has the benefit of known values inside the amp which can simplify the circuit. Obviously, if there were only one way to design a power amplifier, we would all own that design.

More complex designs can include input and output buffers to ensure stable impedance values throughout the circuit though buffers are not technically stages either.

Is a tone control circuit a stage or something else? You tell me.

A Zobel network can be placed on the output stage to protect the amp from the back electromotive force of the loudspeaker motor. Zobels aren't stages either.

Current limiting isn't a stage but it may be in a mass market amplifier.

So, yes, there are stages in most power amplifiers. And a lot of other junk in a lot of mass market designs.

So, what?

"They don't call it a 'phono stage' because horses pull it around.
Phono inputs typically are a stage PRIOR to the first stage of the amp.
You know they are dealing with MV or even UV while a high level input like from a CD player will max out from the 1v to 2v range."

"THEY" can call a phono pre amp anything "THEY" want.

They can call it a phono stage.

They can call it a phono pre amp circuit.

They can call it an inverse RIAA equalization circuit.

They can call it a phono pre amp alone.

There are no rules that apply and most people will understand what you are saying no matter what you call it.

In the Denon it's likely a separate board with a circuit on it.

What's that make it?

Technically, it is not part of anything other than it is a phono pre amplifier circuit. It is located in the pre amp section of an integrated amp and is not part of the stages used in a power amp.

And, if you have a phono input intended for a ceramic cartridge, you don't need any further gain applied to the output of the cartridge. So that's not really even a "pre amp" since there is no gain being applied.

You're arguing in circles. But a phono pre amp is NOT a stage in a power amplifier.


You can even have a pre-pre amp for very low level moving coils - though step up transformers are, IMO, generally superior.

Technically, therefore, a phono pre amp is (often) a pre-pre amp inside the line level pre amp. It's all how you want to talk about it and mostly there are no hard and fast rules, just semantics.

If you have a self contained outboard phono pre amp, is that a stage or simply a phono pre amp?

If you use a step up transformer instead of a pre-pre amp, is that a stage when the gain applied has been derived through a passive component?

You're splitting hairs, leo, just to try to say you weren't wrong. I never said you were wrong about stages. I said what you thought might have happened to the phono pre amp circuit probably didn't and how you are thinking isn't exactly straight.

So, what?

"What I said is true. Plugging in a device outputting a full volt into a circuit expecting 10mv max must come as quite a shock, so to speak."

What you said is not completely true. That's what I said. But that too is arguing over words and nothing else.

It is possible the phono pre amp circuit was damaged, I acknowledged that.

What's your gripe?

I seriously doubt though that the phono pre amp circuit itself was damaged and await further input from T-Bass.

You are free to guess all you want about all the things you can think of to guess about.

This is a mass market, fairly low priced, mid-fi integrated amplifier we're talking about. No mass market manufacturer wants to do unnecessary warranty repairs.

What might determine any possible damage to the circuit would be the overload Voltage of the circuit and the max Voltage of each discrete device in the circuit. The former I simply don't care to look up and the latter is not going to be determined without a schematic - which I don't care to look for.

And we really have no specific idea of the max Voltage applied to the input. Max Voltage for a CD is likely 2V - not always - but it doesn't output 2V RMS. Therefore, there's simply no way to tell.

My guess, as I stated, is the phono section was provided sufficient headroom in its design to allow a less than knowledgeable user to do something less than bright and not send the unit into the shop under warranty repairs.

So I doubt any real, sustained damage would have been done to the phono pre amp itself.

We won't know any more unless T-Bass returns to this thread with further details, will we?

So, what's your point? If you want to argue semantics, I'm not interested.

If one channel has blown a fuse, a shop won't charge just to replace a fuse. However, with a unit of this age, I wouldn't trust any mass market integrated to not have problems that would not result in continued blown fuses. Basically, fuses blow for a reason.

So, ... what?

Oh, yeah, lets talk about Leo's system again.

"Even my Parasound makes an issue of extra gain (could that be another stage of amplification?) for the iPod input."

No, it's not another stage. It's just higher gain in the driver stage. A different op amp most likely. And marketing.

It's all a trade off. Push your devices harder and closer to their limits and you get more noise and distortion. Use more devices at more conservative levels and you change the equation but every time you pass a signal through another circuit, or another active gain device, you are going to add noise and distortion plus phase shifts and time errors.

A designer selects which they prefer, a theoretical fidelity to the input signal? Or, a theoretical adherence to the "best" specs?

Either way, your pre amp and your iPod have nothing to do with this thread. What's the point?


Gold Member
Username: Magfan


Post Number: 3378
Registered: Oct-07
You ASKED about 'gain stages'. I gave 2 concrete examples. take your meds on time.

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 18279
Registered: May-04

"You ASKED about 'gain stages'. I gave 2 concrete examples. take your meds on time."

Where exactly did I ASK about gain stages?

And, where exactly did you give "concrete" examples of anything?

You say "THEY talk about stages" without having a clue about what they are, where they are in a component or the purpose they serve.

You think maybe "your" Parasound - of course we must spend time in every thread discussing leo's gear, we always have to talk about leo's gear!!! - maybe put another amplification "stage" in the circuit just for an iPod?!

Good grief, leo!!! You can't be serious!

First, your Parasound would have an iPod input in the pre amp section, not in a power amp section. And it would be an "input" not a "stage".

Second, no, Parasound did not place another "stage" in the unit just for an iPod input. If they did anything at all other than market this as ready for an iPod input, they used a higher gain chip. In the pre amp section.

Now, the pre amp has "stages" too but this is an input and not a stage. OK?

If this was a "stage", just what you it be called, leo? Stages in an amplifier have names which designate they purpose. Just what would this extra special iPod stage be called do you think?

The "iPod stage"?


You're talking gobbledegook and calling it concrete.

Remind me to never have you pour me a new driveway.

Tell you what, leo, call Parasound and ask about this great new "stage" they created just for an iPod. Ask what they they call this new stage they've created. See what answer you get and report back with that information, eh?

Now you have me curious and I'd like to know what they say. And just how much time they give someone asking looney tunes questions.

Gimme a break, leo. You're full of it.

And you're just pulling "it" out of your rear end, throwing it out and seeing what sticks that I won't totally object to.

Like telling the op to have a shop only look at the phono pre amp because maybe that's the section of the integrated amp that might be broken but we don't know for sure, do we? 'Cause we really don't know what about this amplifier isn't working but you make up BS just to have something to say even when it's total BS.

And, for what reason? We have no idea what has happened to T-Bass' amplifier. He's not here and it doesn't look like he's going to come back to see you arguing BS again.

Why do you do this?

Why do you continue to do this?

If the amplifier is to be used, it needs to go into a service shop that works on old gear. Good luck with that!


That's all you needed to post. No BS about "stages".


Gold Member
Username: Magfan


Post Number: 3379
Registered: Oct-07
From the owners manual of the P5:
Front Panel Aux Input
For your convenience there is an input jack on the front panel for a portable MP3 player (or smart phone). Connect the included cable with 3.5mm stereo plugs between the portable player or smart phone�s headphone jack and the P 5�s Aux input jack. The Aux input has an additional gain stage that boosts the input signal by 12dB so that the volume level remains consistent when you select your other source components. For the best result set your portable player�s volume to at least 75% of its maximum level.

Another gain stage? Coincidence?

Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 18280
Registered: May-04


Semantics are fine.

Details are unimportant.

You continue to prove why you belong to a certain political party. Facts are totally irrelevant to you.

Just like calling a phono pre amp a phono "stage". Semantics don't mean what they say and don't say what they mean.

What Parasound did was insert another op amp with higher gain in the signal path, like I said. They placed it in the input circuit of the pre amp. Not the power amp, and it is not a stage as Elliott discusses a stage which has a discrete task in the signal chain.

Elliott views an amplification stage as you might discuss the systems within a conventional automobile; intake, combustion and exhaust. Adding a different lobe to the camshaft doesn't change those stages of how the system operates.

The camshaft itself is not a another stage. Adding a second camshaft does not add a stage. The camshaft is a part within the intake stage.

The same with an amplifier; the output stage doesn't split phase. The driver stage doesn't utilize buffers. Stages have tasks. Chips simply have gain in your Parasound. Call them whatever the marketing department wants, chips are not stages any more than that second camshaft is a stage.

It's simply another chip. That's all they did. Like I said.

Then they handed that information to the marketing department.

When a single chip can become a stage of amplification, that's marketing voodoo.

Are we done here?

I certainly hope so.

Because NONE of this has a single thing to do with the Denon integrated amp that has one channel blown out.

No shop will only check out the phono pre amp "circuit" and ignore the rest.

And you still don't get to pour my driveway.

You have a distinct inability to answer questions, leo.


Platinum Member
Username: Jan_b_vigne

Dallas, TX

Post Number: 18281
Registered: May-04

The same with an amplifier; the output stage doesn't split phase. The driver stage doesn't utilize buffers. Stages have tasks. Chips simply have gain in your Parasound. Call them whatever the marketing department wants, chips are not stages any more than that second camshaft is a stage."

This is how an engineer, a designer or a technician thinks of the amplification chain.

Inside each stage/link of the chain, they can examine discrete components such as gain devices or phase splitters, buffers or Zobels, NFB loops, etc.

Just as a mechanic can examine a fuel injector within the intake stage. The injector itself is not the stage, is is a part within the intake stage of the entire system.

Likewise, the gain devices are not the stage itself, they exist within a stage of amplification.

What Parasound has done is create a "pre-gain device" for the driver stage of the pre amp just as a pre-pre amp for a mc cartridge is not a "stage" of amplification, it is merely another circuit which provides additional gain prior to the phono pre amp itself.

Not that any of that will convince you to ignore your beloved Elliott's way of thinking and discussing "stages" of amplification.

Believe what you want when it is most convenient to ignore what you previously believed. Accept what the marketers say when it fulfills your biases.

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