Review: Denon PMA-S10 Amplifier

Category: Amplifiers

I was contemplating getting a decent sounding, yet not very expensive headphone amplifier to drive my Sennheiser HD580’s. My dilemma was that neither my source nor my amplification offered me any sockets for headphones. I was using a hand built headphone amplifier put together by a good friend but I was of the opinion that I needed something more powerful and more refined. After doing a bit of research as to what mates well with the Sennheiser and be better than what I have at present, I finally came to a conclusion that there is nothing out there that would really do justice at under $400.

I short listed few headphone amps costing between $400-500 and was about to go ahead with my purchase when I came across a Denon PMA-S10 Integrated amplifier for sale.

During my initial checking on the web I was surprised that there was hardly any information available on this amplifier, except for the fact that it is prominently listed on the Denon’s Japanese website. The only information available was the list price (J. Yen 220,000 which calculates to be $2,200 at the prevailing exchange rate back in 1995) and basic power output which is stated at 50 watts/ch into8 Ohms and 100 watts/ch into 4 Ohms! There are not many integrated amplifiers out there which actually double in output power as the resistance is halved at the speaker end. Nonetheless, specs are only guidelines and they cannot possibly give any indication of how an amp will actually sound like. It’s only during the listening/evaluation that you find out what the amp is really capable of.

Let’s get on with the Denon PMA-S10, shall we?


This amplifier was mainly sold in the Japanese domestic market and therefore is available in only in 100 Volt version. Some of the other models from Denon in the ‘S’ series are also being sold in same way along with a transformer suitable for use with local electric supply and giving an output of 100 Volts.

This amplifier tips the scales at just above 15 Kg’s! For a 50 watt amplifier this is a monster. Even the Krell KAV-300i with 150w/ch weighs less than this, an amplifier which I never liked. There is another model of Denon which is very popular with audiophiles, although I have not heard it but I am to understand it is a direct descendant of the high-end 'S' series of Denon amplifiers, notably the Denon PMA-2000

The front fascia, in champagne gold finish is typical of what a classic 70's amp would look like. The quarter inch thick front panel, large volume control, and an equally large selector switch. There is a rec-out selector, tone defeat button (to disable the bass, treble and balance circuitry) and finally a power button (with a small yellow light to indicate the amp is switched on). The bottom of the amp is all shiny copper.

The back side of the amp features very solid speaker terminals ( for a single pair of speakers) which are fully gold plated as well as all the inputs provided. Next to the phono socket there is a black button which switches back and forth from MM to MC. Detachable three prong input power cable receptacle is provided to power the amplifier. Three flat pin output receptacles to feed other equipment if need be are also provided.



Rimsky-Korsakov: Scheherazade; Stravinsky: Song of the Nightingale (RCA Living Stereo)
Michel Camilo - Live at the Blue Note
Eleanor McEvoy – Yola
Sting – Sacred Love
Santana – Abaraxes
Shaft (Original Soundtrack)
Casino Royale (Original Soundtrack)
Roxy Music – Avalon

Dave Grusin – Gershwin Connection
Supertramp – Breakfast in America
Patricia Barber – Cafe Blue
Cassandra Wilson-New Moon Daughter
Dominic Miller – Shapes
Ella Fitzgerald and Louis Armstrong – Porgy and Bess
Joni Mitchell – Clouds, Both Sides Now
Keb Mo – Slow Down

Sonny Rollins – Cool Struttin’
Peter Gabriel – So


Chartwell LS3/5a (15 Ohm Version)
Rogers LS3/5a (11 Ohm Version)
Energy XL-25 (8 Ohms)belonging to a friend
Kef Reference 2 (4 Ohms)


The evaluation/comparison of the amplifier was done over a period of 4 weeks and critical listening was done each time only after the amplifier was in operation for at least 45 minutes.

This amplifier is very sensitive when it comes to power supply since I did a test on 110 Volt supply and the sound from the amp was not anywhere near what it was capable of producing when proper power feed was given through the step down transformer giving 100 volt output to drive the amplifier.

After acquiring the Denon, I shelved the idea of getting a headphone amplifier, since I found this amplifier so good for driving the Sennheiser, that buying a $400 headphone amplifier would really not be a big upgrade for me. They only possibility to get really good sound would be for me to spend in access of maybe $500-1000 to really better the Denon in every respect. The amplifier was capable of giving me a good ear massage driving the Sennheiser at just 10 o'clock position.

The tone defeat button on the amplifier when checked through the headphones gave me an indication that the all the bells and whistles incorporated in terms of circuitry are of very high quality as the difference was hardly noticeable. Nonetheless, for the sake of record it should be noted that all the listening/evaluation was done with the the circuitry bypassed.

Now that I realised how good the Denon was for driving the headphone I was really curious to find out what it would sound like when driving real world speaker load even though I did not get it for this reason. I did not test the amplifier with just 4 different type of speakers, but, all posing a very different type of load to the amp from 4 to 15 Ohms.

Denon managed each speaker gracefully and did not give me even the slightest of impression that it was struggling at any stage even when pushed and called upon to deliver the dynamics demanded by any particular piece of music. Not many amps are capable of driving a variety of load, let alone sounding musical and at the same time having an effortless delivery. A remarkable feat indeed for an integrated amp since I have tested different speakers and found many amplifiers are good at driving either high impedance or low impedance loads. There are exceptions indeed, but, when we generally talk about exceptions it really means some high-end amplifiers costing several thousand $$$.

Rimsky Karsakov's Scheherazade as most would know, is a pig to reproduce, this piece of war music can easily trip any unsuspecting amp and speaker combo when it approaches its climax, the Denon sailed through and maintained the integrity of the music pretty well.

Listening to the Eleanor McEvoy's Yola (the first track), the amplifier gave me an indication of how good it is when it comes to the background noise, it was absolutely silent and only the music was being reproduced, there was no hint of any hiss or noise, this means the amp's noise floor is way below the audible range. I not only sensed it when using the speakers but also when listening to it through the Sennheiser. There was none of the very annoying upper midrange or lower treble grain, glare, or hardness that we often hear from typical Integrated amplifiers.


My main amplifier was the Quad 606II and Pre amplifier being the Quad 66, there is of course the difference in power rating, 140 watts/ch for the Quad versus 50 watts/ch for Denon. There was obvious difference when it came to driving the speakers authoritatively, the Quad was in a different league, nonetheless, the Denon gave me an impression that it was more like an 80 watt amp rather than the specified 50 watts/ch. The only difference between the two amps was the midrange, the Quad had a very liquid like midrange in comparison to the Denon, it had that uncanny ability to extract a bit more detail than what the Denon could. The voices had sort of an aura around them when it came to Quad and the Denon was sort of flat sounding. Nonetheless Denon is certainly not laid back, if I have to describe its reproduction of the entire audible range, it was more towards being flat without highlighting any particular frequency range.

The sound stage on the Quad was much bigger, from back to front as well as from left to right when compared to the Denon. Listening to Keb Mo's album Slow Down and particularly the third track “Everything I need”, just when the word “everything” is being rendered, the bass was sort of circling around the two speakers like the Ring of Saturn circling around the planet, with Quad, the ring was larger and denser. I guess this also could be attributed to the difference in power output, but, it sure was the case when comparing the two.

When comparing the Phono Stage I felt the Quad was superior. Denon was a bit thin sounding, unlike the Quad which if I dare say it, was lush sounding and had more authority. Again the midrange had the same characteristics as mentioned earlier.


There is of course certain advantage when it comes to Integrated amplifiers. Combining power and pre-amplifier means all the functions are put into a single chassis saving costs in terms of power supplies and doing away with one additional chassis. Hum is reduced because amplifier and pre-amplifier now share exactly the same ground voltage, so less shielding is required The need for an additional interconnect is also not there if it is a single chassis, the preamp output buffer and power amp input buffer is also done away with. An integrated amplifier allows the design engineer to design the pre-amplifier output circuit and power amplifier input circuit to be an almost perfect match since the characteristics of the interfaces are known. This is an established method of delivering high performance in a more convenient and cost-effective package.

The Denon PMA-S10 is a very good integrated amplifier with more than sufficient power for even difficult to drive speakers; it delivers clean, detailed, and neutral sound that integrates well with any speakers; at the same time it has an excellent build quality that makes for a very impressive product indeed.

This is not an amp for those who are looking for an upfront and in the face music, but, this is an amplifier one can listen to for hours without experiencing ear fatigue.

For the price that I paid for this amplifier, it would have been a stupid mistake on my part if I had let the opportunity pass-by, it was too good a deal at just $250! To be honest, this amplifier would be a worthwhile purchase even at around $600-800 provided one can come across one.

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Great review. I've been wondering about this Amp for while. Whish the U.S would get more high-end Japanese stuff like the PMA-S10 but that may never happen. I've owned some of the recent Luxman gear (L-507f) factory converted by Lux in Japan very musical amp.

Thanks for the feedback. Yes, its a pity that more of these amps do not make it to the US, but, the Japanese domestic products always are of high quality which many do not get to even see. I had purchased in 1984 a Sony walkman while in Tokyo which I never saw being introduced in teh international market. It was a wonderful pieces of equipment and very tiny running on just a single AA cell upto 4 hours of continous use. The entire thing was brushed stainless steel, no plastics!

As for Luxman, I have come across some of their very good models and they are made beautifully and sound good too. In particular some of the hybrids were just fantastic.

Thanks again for commenting on the review, appreciated.

Clear and warm sound......absolutely not the Japanese sound....I couldn't say it's a powerful amp (Although it has 50W x 50W at 8ohm ) but I can say it a honest amp ( I meant it able to let you hear the turth that how's quality of the source you playback).

Actually, My system is McIntosch Int amp MA6900 to match the B&W 802D ...These matching quite balance and great sound, but don't forget how much of them!!!..that should reasonable of my paid!!!

I had got the Denon PMA-S10 from my friend on last year ( Because he leave US to Hong Kong ). I took it back to home and placed it in my basement almost half month. Finally, I had connected it with the B&W 802D on a holiday. In fact, I have no expected it could reward me any suprise ( Might be the pric eand it's output power !!)......but amazing was after I pressed the power switch, and played my favorite CD - Jean Michele Jarre live in China 2004..........I was wondered the sound isn't really performed by the Dennon?? How's crystal clear, solid bass, balanced mid and high, quick response, instrutmental's position, sound dynamic ..........remember that amp just US$2200 when brand new and the MA6900 was US$5230 !!!

Sorry for I couldn't express my feeling of this amp by words!! I just want to tell to all friends that you should try to hear or own that amp to proof my words is turth or not!!

At the costing of the MA6900...... I thought Mc must be work harder to make the customers to spend the money is worth, huh..........

Please feel free to strike back if any objection.

Many thanks and regards,
Andrew Sean Jean Rene

Your comments very much appreciated. Thank you very much for taking time out and responding to the review I did.

It seems like those who know about this amplifier have praised it very highly. There was another gentleman at AA by the handle "scytales" who seem to know a great deal about this amplifier which I think is useful for sharing it here for the members.

I quote:


Nice review. Thanks for having written it.

I myself own the further evolution of your S10, the PMA-10II. Actually, the S10II is more of an evolution of the monobloc combo POA-S10 with passive line preamp than an evolution of the PMA-S10.

Some comments on your nice text, as I have all the schematics of Denon S1 and S10 amplifiers and preamplifiers components.

First, the PMA-2000 is very different from the PMA-S10, despite the fact that the further models (PMA-S10II, PMA-S10III, PMA-10IIIL, PMA-SA11) share the same chassis than that of the various PMA-2000 marks.

The PMA-S10 have a circuitry near to that of the PMA-S1, but in non-symmetrical fashion. There is essentialy a cascode final stage, with a single pair of UHC-MOSFET capable of 30A continous each and associated with bipolars to keep the drain voltage of the UHC-MOS at a constant by following a magnifyed version of the input signal in the BIAS stage.

A very nice design IMHO. Nelson Pass advocates that cascoding even the output stage of an amp does permit to approach the caracteristics of class A operation and gives a feeling of power well beyond the actual power ratings thanks to the elimination of large amount of what he names "compressive intermodulations".

Apart from this technical details, I am agree with your comments about the sound of the PMA-S10, as I recognize most of what I think about my PMA-S10II. Nevertheless, the 100W/8 ohms rating of the S10II should overcome a large amount of the weaknesses you have noticed due to a lack of power.

A last word about the current capabilities of this amp. You noticed that it is rated to double its power when the load impendance halves from 8 to 4 ohms. The oldest specifications of Denon S series suggests that nor can it, but is it also able to double its power under 2 ohms on musical signals. Denon do not provide such detailed specs nowadays, but there is no clues that the continued S series amps do not have the same ability than the discontinued ones. Especially after having saw measurements of the S10II which shows that the impulse power equals the continuous power with both channels driven under 8 and 4 ohms, suggesting quite a beefy power supply.

Finally, after have a look insinde of my amp and on others of the S series, I second you when you say that the built quality is very good. Actually, it is really outstanding for the price!
Andrew Sean Jean Rene,

I am very surprised that the PMA-S10 you tried has enough grunge to dive a pair of B&W 802 Diamond, considering the power-hunger reputation of those loudspeakers.

Did you try this Denon amp with other music style than J-M Jare?
Update on the Denon PMA-S10

I have now had this amp for just over a year and I have discovered a few more things about this wonderful amplifier.

Couple of weeks back a friend of mine was very keen to hear the Denon and we had a session listening to it on Sunday afternoon. We started at around 12 noon to be followed by lunch and back again with our listening. The lunch was forgotten and the session lasted 7 hours of continuous listening.

Track after track we continued and the Denon seemed to open up more and more. At one point the bass of the amplifier was so authoritative and controlled and that is when I realised that it beat my Quad hands down in that department. I had also been listening to the Primare A30.1 (review posted)and I could not fault the Denon in any way with regards to Primare. The difference of power out put was there but not so in the way the Denon had control on the Kef Reference Two's.

The long session and the amplifier getting really warm probably had a lot to do with the way it sounded. I even felt that midrange was now close to what the Quad was able to resolve, Quad seemed to be having a slight edge but overall the Denon had more to offer in both the highs and the lows. Could it be that the lack of bass in the Quad made it sound the way it did? Denon was calling attention to the overall sound whereas the Quad had only the mids to its advantage.

One thing is certain that this amp really needed a very long session to really come out on its own. We went ahead with the entire session with volume knob at almost 12 O'clock position for all types of music.

When I reviewed the amplifier earlier I had not had such a lengthy session in one go and that too with volume at such high position. All in all this amplifier in my opinion has more to offer than what I was lead to believe at the time of my initial review, even though I was very impressed at that time with its performance.
Bought this amp 2 weeks ago. before hat i've read this review and i can honestly say that all is true. It drives my Jbl century gold's with firm grip and doesnt let go. The amp sound really in control. Its very fast compared to my marantz pm17mk2 en less laid back. Further more ididnt get the chance to turn it up past (lets say) 9 óclock and then the sound is huge but not irritating. The marantz i had turned up to 10 óclock but didnt match this sound level. Cant understand why.
thnx for the review (payed 400$)
I have had the PMA-S10II for ten years now having bought it from a Hi-Fi shop ex-demo when I arrived in New Zealand. In all that time, I have come to love this 30kg beast. Even better they did the running in of 100 hours with the shop's electricity!! Its twin transformers are two of the biggest draw cards and the sound manages to convey everything effortlessly with the Linn Ikemi CD player and now Wadia 151 decoding computer DAC. With plenty of quality outputs at the back (XLRs too), and so much power you will not be disappointed; it also does get better as it warms up. I never regretted this large purchase. Infact I love it so much I want it buried with me!! It has been with me through all life's emotions and highs and lows delivering quality music from all styles without complaint or flaw.

Make no mistake this amp kicks ass; it is a pro piece of gear, which will never disappoint......... Again let your ears be the judge long after the 2013 salesman has whined himself into a corner about how you need to replace it......