Power Amps, An Overdue Addicts Guide

[Cafad]

Well it’s been a long time in coming but it’s finally here.  Part of the reason it took so long was that it’s difficult to start a project like this because that first amp is both evaluated and stipulated at the same time.  So if I give amp number 1 a seven for its bass performance then I’m saying that it has very good bass performance and that every amp that follows will be compared to that level of bass that is now stipulated (ie: set in stone) as a seven.  You could say that I’ve declared that level of bass as a seven rather than evaluated it as a seven.  In a way you have to listen to several amps to get an idea of the level of variety you expect before that first amp can actually be evaluated.

 

Anyway, I have managed to wrap my oblong noggin around the concept so here we go with the very first Power Amp entry. 

 

1.  Burson PP-160.

This is an amp I quite enjoy listening to, I’ve described Burson gear in the past as sounding crisp, snappy and airy and this amp is no exception.  I should probably add detailed to that list as the performance of this amp is very good.  It is not an amp to puff up its chest and announce its presence so at times it does seem to be a bit lazy because when the music dies down the music really does die down, but when called on it gives an excellent performance with nicely extended, airy highs (with a very nice “twinkle†effect on the triangle and piano), snappy mids (with transients in between that are very pleasing to the ear) and nicely defined deep and clean bass.

What’s more Burson gear tends to keep this sound across a wide range of components that it is paired with, I think it may be partly due to the fact that it has a very even representation of the entire frequency range (so it does not emphasize highs, mids or bass).

The PP160 is a stereo power amp with 70 watts per channel into 8 ohms and only one RCA input.  It does have a booster amp function so that a lowish (sub 25 watt) valve amp can be plugged into it via a pair of “speaker in†binding posts but mine has been disconnected internally so I can’t test that function out.

 

Test Rig.

The Burson was fed from a Consonance CD120 via LBP Parapiao ICs into a Burson PRE-160 and then via Ribbonflex ICs into the PP-160.  Then via Ribbontek speaker cables into my Lenehan S2Rs on their matched stands.  Power was fed to all source and preamp components via a Consonance PS1 power filter board and to the PP-160 via a PS3 power board.

 

Detail Highlights.

Highs:  Nice twinkle on triangle and piano, less air than there was when used with the Osborns.  7.5

Mids:   Good snap, not as crisp as on the Osborns, excellent transients and nice airy space in between each instrument.  7.0

Bass:   Deep and clear with distinct impact, depth and decay evident on drum strikes.  7.5

Vocals:  Accurate and clear with female vocals clear in top end.  F: 7.0  M: 6.5 

Average: 6.75

2D and 3D Soundstaging:  7.0 each, instruments nicely separated and placed within the stage.

Overall Performance Integration:

Doesn’t excite in the short term, but if you stick with it you come to realize just how capable this amp is.  An excellent listening amp that does not over emphasize any one part of the performance.  It took a swap to another amp to make me realize just how good this one actually is, an excellent listening amp but not really a party amp.  I would describe it as subtly brilliant and I’m giving it an 8.0!

 

Ability to Emote:  6.5  Let down by a slight dryness in the mids, it believes it is up to you to enjoy the music, not it to make you enjoy the music.

 

Electric Guitar Test:

7.5  Very good, very accurate, if it just had a tiny bit of agro energy (and I mean a very, very small bit) it would be a 8.0.

 

80s Rock Test:

Everything is as it should be, including the tape hiss in the background (which is a bit of a mixed blessing).  7.0

 

Total Score:  71.75

 

I think this was an excellent amp to start with, it sets the bar a bit high but why not, right? 

Pics will be added just as soon as I find the charger for the camera.

 

Edit:  And I did.

                

At rest.                                                                        And ready for action.

 

And in the interest of full disclosure.

I am a Burson fan, every piece of Burson gear I've heard has been what I would call "above average" in performance and very well built.  I have made every effort to conduct this evaluation in a fair and impartial manner. 

Though not necessarily in a mature one.

The chair in use was a recliner of acceptable comfort level with adjacent shelving that is frequently used as a drink stand.  The air conditioner was not in use for the review and I suspect this is the reason that the ice in my Pepsi melted long before I was finished.  My long haired cat was strangely absent for the review so it worked out well that the room heated up a little as my feet would have been a bit cold otherwise.

 

Scale:

1 to 3 means a performance below par with one being somewhere in the vicinity of fingernails on a blackboard while a poorly tuned AM radio shrieks out static in the background and 3 being just bearable but still rather messy.

4 to 6 is average, listenable but nothing noteworthy, 4 being a bit messy or harsh and 6 being pretty good but nothing to write home about.

7 to 9 is better than you would expect them to be, with 7 being a good performance, 8 being an exceptional performance and 9 being the best you are ever likely to hear.

And it is pretty damn unlikely that I will ever award a 10 because that would mean it is the best of the best of the best.

(Add them all up for a final score out of 100, and remember from 30 to 60 you can go from an absolute stinker to an amp that is pretty good at what it does, anything above 60 is likely to be something worth investigating)

 

 

Next up is a stalwart of the power amp industry, the Rotel RB1070 which have on loan from ellrots.

Edited May 5, 2013 by Cafad

[Guest Muon]

Nice!

 

And I wish more reviwers would include things like this...

 

"The chair in use was a recliner of acceptable comfort level with adjacent shelving that is frequently used as a drink stand.  The air conditioner was not in use for the review and I suspect this is the reason that the ice in my Pepsi melted long before I was finished.  My long haired cat was strangely absent for the review so it worked out well that the room heated up a little as my feet would have been a bit cold otherwise."

 

Seriously, I do like how you do these reviews.

 

Cheers

 

Edit: Ooo...I had one of those Rotels briefly, will be interesting.

Edited May 5, 2013 by datafone

[buddyev]

Thanks for the informative review, Cafad.

Excellent timing for me as I'm on the lookout for a power amp to go with a Nad M51.

[Cafad]

Nice!

 

And I wish more reviwers would include things like this...

 

"The chair in use was a recliner of acceptable comfort level with adjacent shelving that is frequently used as a drink stand.  The air conditioner was not in use for the review and I suspect this is the reason that the ice in my Pepsi melted long before I was finished.  My long haired cat was strangely absent for the review so it worked out well that the room heated up a little as my feet would have been a bit cold otherwise."

 

Seriously, I do like how you do these reviews.

 

Cheers

 

Edit: Ooo...I had one of those Rotels briefly, will be interesting.

 

Thanks Datafone.  Just a little lighthearted dig at the audiophiles who insist that tiny, strange things like those can affect the sound quality.  I have to back them up on some points though, the addition of an old "Pumped Up Down Under" poster to my wall certainly made me appreciate my listening a whole lot more than I did previously.

 

 

Thanks for the informative review, Cafad.

Excellent timing for me as I'm on the lookout for a power amp to go with a Nad M51.

 

Not a problem buddyev, I aim to please. 

 

The Rotel review will be up later this afternoon, just as soon as I've finished watering some pawpaw trees.

[buddyev]

We really need a comparison of a cat-free vs cat-present listening environment. It would also be good if you could borrow a range of different breeds of dog. So no short cuts please, cafad — your credibility is at stake.

Edited May 6, 2013 by buddyev

[Cafad]

2.  Rotel RB1070.

After I finished with the Burson I swapped straight to the Rotel and my initial impression was a very good one.  The Rotel sounded more energetic, more dynamic, almost addictive in its delivery.  After listening to it for about half an hour though I realized that the energy and dynamicism was due to a boosted midrange and its efforts in the highs and lows leaves a bit to be desired.  The bass wasn’t as deep and the highs certainly didn’t sparkle as well as the Burson, also the detail was blurred by the mid range boost and the Rotels bright sound (with a touch of glare).  The RB1070 didn’t sound as bright as my memories of the RA1520 (no surprise there, different speakers, different pre) but that brightness certainly makes it easy to identify as a close relation.

 

 

The RB1070 is a stereo power amp with 130 watts per channel into 8 ohms and only one RCA input.  It is able to be bridged internally to give over 300 watts as a monoblock.

 

Test Rig.

The Rotel was fed from a Consonance CD120 via LBP Parapiao ICs into a Burson PRE-160 and then via Ribbonflex ICs into the PP-160.  Then via Ribbontek speaker cables into my Lenehan S2Rs on their matched stands.  Power was fed to all source and preamp components via a Consonance PS1 power filter board and to the Rotel via a PS3 power board.

 

Detail Highlights.

Highs:  Brightness in evidence, reasonably nice but a bit of breakup on metallic sounds, steel guitar far too bright and glarey.  5.5

Mids:   Sweet, energetic, dynamic, a definite mid range boost over the Burson, detail a bit fuzzy, slight impact emphasis on drum strikes  7.5 initially but drops to a 6.0 with listening fatigue setting in within an hour.

Bass:   Strong, fairly deep, still a bit fuzzy.  5.5

Vocals:  Clear but lacking a bit in definition, female vocals do not sound as sweet in the highs as they should .  F: 5.0  M: 5.5 

Average: 5.25

2D and 3D Soundstaging:  5.5 for 2D, the mid range boost makes imaging less distinct.  5.0 for 3D, everything works but it’s a bit messy and lacking in the ability to lock an instrument in from a particular position.

Overall Performance Integration:

Pushes its mid range performance out in front and makes the most of it but it really just acts as a way to cover its deficiencies in the highs and lows.  The mid range is addictive but that fades away as the brightness and glare sink in.  Has a high initial FTF.  Initially a 6.0 but falls to a 5.0 over time.

 

Ability to Emote:  Draws you in right from the start, gets your foot tapping and your head bouncing.  Just not for long enough, in my opinion.  7.0 initially but drops to 5.0 with time.

 

Electric Guitar Test:

Good energy, but too bright, I could feel it in my teeth (and everyone knows you should be able to feel an electric guitar in your skull and your ribs before your teeth!).  5.5

 

80s Rock Test:

Good, but not outstanding.  6.0

 

Total Score:  59.25 on initial listening but it drops to 54.75 as the brightness and glare ramp up the listening fatigue.

 

So what we have is an amp that is decent overall but wears on the listener a bit as the album spins on.  A good party amp but not one that I’d use for extended listening.

 

Scale:

1 to 3 means a performance below par with one being somewhere in the vicinity of fingernails on a blackboard while a poorly tuned AM radio shrieks out static in the background and 3 being just bearable but still rather messy.

4 to 6 is average, listenable but nothing noteworthy, 4 being a bit messy or harsh and 6 being pretty good but nothing to write home about, to rate above 6.0 the component has to give that something extra.

7 to 9 is better than you would expect them to be, with 7 being a good performance, 8 being an exceptional performance and 9 being the best you are ever likely to hear.

And it is pretty damn unlikely that I will ever award a 10 because that would mean it is the best of the best of the best.

(Add them all up for a final score out of 100, and remember from 30 to 60 you can go from an absolute stinker to an amp that is pretty good at what it does, anything above 60 is likely to be something worth investigating)

 

I’m not certain which direction I’ll go next but I can guarantee that monoblocks will be involved shortly.

 

I did most of the listening to the Burson and the Rotel on the same night, I thought I’d start the thread off with a bit of a bang and get them both written up pretty quick.  With luck there will be another addition before the end of the week.

[Guest Muon]

Again, nice review

 

Those Rotel's certainly need a well matched pre, I only listened to the one I had briefly through a passive pre I put together with a cheap but quiet pot, the highs nearly made my ears bleed.

I imagined they could be a lot nicer with a warm SS or a valve pre.

[Rob181]

Really enjoy your reviews Cafad...you tell it like it is...using the same benchmark for all...a good read & they only get better...your reviews that is...Rob

[Cafad]

Again, nice review

 

Those Rotel's certainly need a well matched pre, I only listened to the one I had briefly through a passive pre I put together with a cheap but quiet pot, the highs nearly made my ears bleed.

I imagined they could be a lot nicer with a warm SS or a valve pre.

 

I remarked a while back how the Myryad Z142 when used as a pre seemed to be a pretty good fit with the Rotel RB1070 so it can be made to behave, but yes, careful pre selection is a must with a rotel.

 

 

Really enjoy your reviews Cafad...you tell it like it is...using the same benchmark for all...a good read & they only get better...your reviews that is...Rob

 

Thanks Rob, it does feel good to be back actively reviewing again.  It feels like I've been away for so long!  No more changes to speakers or room for a while, I've got some catching up to do.

[Al Leece]

Love your work, especially since I have recently dived into the power amp market and even more recently upgraded to monoblocks...

[Cafad]

Love your work, especially since I have recently dived into the power amp market and even more recently upgraded to monoblocks...

 

Are they Arcam monoblocks?  I don't see them in those pics in your sig but I do see an Arcam amp and disc spinner.

[ellrotts]

So, when are you going to write up my Luxman?

[Cafad]

So, when are you going to write up my Luxman?

 

I've only been home for 2 1/2 hours mate, give me a chance!  Some people, rush, rush, rush.

 

I'll fire it up soon.

[Al Leece]

Are they Arcam monoblocks?  I don't see them in those pics in your sig but I do see an Arcam amp and disc spinner.

Nope - the Arcam is a pretty good amp in its own right and I am mainly using it as a pre-amp to a pair of Wyred4Sound mono-blocks, which replaced an ME85 I had been using to power the bass and mids on the PMCs. The W4S are certainly an upgrade on the ME85 and I have not got to listen to my familiar reference recordings yet.

 

I do need to update my sig pics... Maybe soon... ;-)

[Cafad]

We really need a comparison of a cat-free vs cat-present listening environment. It would also be good if you could borrow a range of different breeds of dog. So no short cuts please, cafad — your credibility is at stake.

 

Apart from the foot temperature there is very little difference to be heard between a cat-free and a cat-present listening room. 

Dogs on the other hand do have more of an impact.  Fox terriers, being small and having short fur are similar in sonic signature to your average cat but the addition of an Irish Wolfhound to the listening room is almost as good as an additional thick floor mat.  Better than most floor mats actually, as their fur is hypoallergenic and they do not shed, a big plus when time comes to vacuum, however they do have an unnerving habit of sticking their nose in your ear while you are trying to listen to music (Ned, my sisters Wolfhound, is 60kg and stands about 4ft high so unless you are sitting on a stepladder he is quite capable of reaching your ear), even worse is that if you manage to ignore their polite request for attention (and by that I mean the whole nose in ear thing) they can then jump into your lap.  This can ruin not only your day but also your future prospects for successful procreation.

 

As if that wasn't enough (and I think it is, I really do!) I have determined that the trip hazard presented by having a dog present is not at all directly proportional to the size of the dog, you'd think it would be, but no, it is not.

 

Safer to keep the pets out of the listening room I feel.  Far, far safer!

[avalon27]

really like reading your reviews as im in the market for a power amp to run my 1-93 vaf speakers

[ellrotts]

Apart from the foot temperature there is very little difference to be heard between a cat-free and a cat-present listening room. 

Dogs on the other hand do have more of an impact.  Fox terriers, being small and having short fur are similar in sonic signature to your average cat but the addition of an Irish Wolfhound to the listening room is almost as good as an additional thick floor mat.  Better than most floor mats actually, as their fur is hypoallergenic and they do not shed, a big plus when time comes to vacuum, however they do have an unnerving habit of sticking their nose in your ear while you are trying to listen to music (Ned, my sisters Wolfhound, is 60kg and stands about 4ft high so unless you are sitting on a stepladder he is quite capable of reaching your ear), even worse is that if you manage to ignore their polite request for attention (and by that I mean the whole nose in ear thing) they can then jump into your lap.  This can ruin not only your day but also your future prospects for successful procreation.

 

As if that wasn't enough (and I think it is, I really do!) I have determined that the trip hazard presented by having a dog present is not at all directly proportional to the size of the dog, you'd think it would be, but no, it is not.

 

Safer to keep the pets out of the listening room I feel.  Far, far safer!

Stuffed animals alternately allow the feel of a beloved pets company while acting as a fantastic bass trap when correctly placed.

 

Im working on a pair of elephants - I estimate I will need animals that large to fix my issues

[Cafad]

Stuffed animals alternately allow the feel of a beloved pets company while acting as a fantastic bass trap when correctly placed.

 

Im working on a pair of elephants - I estimate I will need animals that large to fix my issues

 

I reckon a pair of stuffed Polar Bears would look awesome in the corners of that room of yours.  Nice thick fur too!

[bruce108]

If you had a yeti, he - or of course she - could listen along, as well as trap bass. Though they do tend to want the sweet spot.

[Cafad]

If you had a yeti, he - or of course she - could listen along, as well as trap bass. Though they do tend to want the sweet spot.

 

This is true, but good luck holding on to your chips, popcorn or M&Ms with a Yeti in the room!

 

OK, I think I've led this thread of mine far enough off topic. 

Next up will be the Perreaux Silhouette SX60m Monoblocks, the listening is all done I just have to get the typing sorted.  It'll be up later tonight if all goes well.

[Cafad]

3.  Perreaux Silhouette SX60m.

Amazing!  I don’t know how they do it but that 60 watts manages to sound just as powerful as the Rotels 130.  Strong and yet subtle, strong and yet clear, strong and yet honest, but above all, strong!  And this is on 86dB speakers!  I have yet to hear any amp that gives an instrumental performance as good as these, for want of a better word they just sound genuine.  In fact all of the Silhouette’s sound is very honest, to the point where it scores a little lower in the vocals because it sorts the divas from the wanabes.  It doesn’t help the vocals sound good, it just gives you what’s there and lets you decide.

 

Honest is a good word to describe these little amps, they just feel like they are adding nothing and taking nothing away.

They give excellent full, fast, strong bass, great to listen to at low volume levels but they can get a little bit dry at higher ones (say above 85dB). 

 

The Perreaux Silhouette monoblocks are a mono power amp with 60 watts per channel into 8 ohms (75 into 4), one RCA and one balanced input.  It also has one RCA and one balanced output for daisy chaining.  Each one weighs 2.5kg and both will fit inside the same shoe box!

 

I had some issues with transformer hum (or what I thought was transformer hum) throughout the test, so I pulled the tops off them this afternoon and tested out a few pieces of shielding around the torroid.  I couldn’t find any real difference but I did stumble on the source of the hum, it was coming from an IC!  Swapped the IC out and the hum was gone (and now I have to figure out what I did to the IC, stupid expensive audio hobby!)

 

Test Rig.

The Perreauxs were fed from a Consonance CD120 via LBP Parapiao ICs into a Burson PRE-160 and then via Ribbonflex ICs into the monoblocks.  Then via Ribbontek speaker cables into my Lenehan S2Rs on their matched stands.  Power was fed to all source and preamp components via a Consonance PS1 power filter board and to the Pereauxs via a PS3 power board.

 

Detail Highlights.

Highs:  Very honest, gives the impression of breakup starting on triangle but stops short of actually breaking up, not sweet in the highs but not false either.  6.5

Mids:   A touch too honest to be sweet on the ears but an impressive performance that makes you want to listen longer because you feel that you can hear more going on.  6.5

Bass:   Strong, clean and able to both resonate and decay in a very believable manner that reinforces the feeling of honesty.  7.5

Vocals:  Good but female vocals lose a little in the highs, male vocals seem slightly less “croonish†and more gravely but both sound ‘correct’.  F: 6.5  M: 6.5 

Average: 6.5  (finally, I hate this average bit giving me a final score that delves into quarters of a point!)

2D Soundstaging:  8.0  Instrument separation is very sharp, instrument and channel separation is extreme! 

3D Soundstaging:  8.0  I can place the drums around the drummer, Eric Carr’s work never sounded so good!

Overall Performance Integration:

The PRAT takes a little time to catch on because you tend to pay attention to each instrument individually rather than the song as a whole, everything just sounds so honest (yeah, yeah, I know, over used word, but there are only so many to choose from) that each instrument is worth listening to.  Once that fascination wears off though, you can really immerse yourself in the song.

5.5 to start but rising to 7.0 over the course of about 4 or 5 songs.

 

Ability to Emote:  6.0 initially but rising to 7.0 with time.  Clear, accurate and detailed sound but not smoothed or sweetened.  As with a good cup of straight coffee it could be said to lacking some character.  It takes a little time to appreciate its virtues. 

While this may not be the type of emotion I originally intended when I created this category I managed to get very excited when I heard 3 stereo and instrumental effects on my standard test disc for the very first time, and excitement is an emotion so it gets an extra plus one for effort.  7.0 and up to 8.0 with time.  There also seems to be an entire conversation going on in the background of a song I played just on a whim, never even knew it was there before!

 

Electric Guitar Test:

8.0  The best yet!  No sense of energy or sweetness just a strong, loud guitar that sounds so good you love every second of it. 

 

80s Rock Test:

6.5  The amps are good enough that several of the imperfections of older rock music show through.  The music still sounds good, but it also sounds a bit old.

 

Total Score:  70 rising to 72.5 as you figure out just what you are hearing and how good it really is.

 

So what we have is a pair of little amps that are excellent in their abilities, display far more power than expected and are an excellent example of what can be achieved in a small form factor.  If you love instruments then these are the amps for you, but if vocal sweetness is your chosen audio drug you should probably look elsewhere.

 

Scale:

1 to 3 means a performance below par with one being somewhere in the vicinity of fingernails on a blackboard while a poorly tuned AM radio shrieks out static in the background and 3 being just bearable but still rather messy.

4 to 6 is average, listenable but nothing noteworthy, 4 being a bit messy or harsh and 6 being pretty good but nothing to write home about, to rate above 6.0 the component has to give that something extra.

7 to 9 is better than you would expect them to be, with 7 being a good performance, 8 being an exceptional performance and 9 being the best you are ever likely to hear.

And it is pretty damn unlikely that I will ever award a 10 because that would mean it is the best of the best of the best.

(Add them all up for a final score out of 100, and remember from 30 to 60 you can go from an absolute stinker to an amp that is pretty good at what it does, anything above 60 is likely to be something worth investigating)

 

There we go, monoblocks have now been represented.  Next up will be one of the two amps that I borrowed from people who now want them back (they know who they are!).

 

Edit: Added pics.

 

            

Edited May 14, 2013 by Cafad

[Willco]

Good work Caffy boy--you have been a busy little Vegemitey!

 

The venerable Perreaux Amps-- some good some not so--these seem to have risen above the fondue--maybe add RRP or price purchased/or loan from/etc so we have an idea of value per se with your reviews.

 

Hope you realize this could be a vote in the Mosfet camp-Ha!

 

Good Listening and looking forward to catching up when I'm back from the Styx.

 

Willco

[Cafad]

Hi Willco, I have left out the RRP's haven't I?  I'll start including them from now on but for the purpose of catching up the Burson PP-160 was circa $2200 when new, the little Perreauxs all seemed to sit between $1000 and $1200 when new. 

I can't find a new price on the Rotel, can anyone help out there?

[cheesehead]

Mmmm, mono blocks are nice little beasts, assume they're no longer available new?

Would be interesting to know how they compare to the current Audiant 100P stereo amps?

Tks for your reviews, really enjoyable!!

[Phantom]

Thanks for a great review Cafad, your reviews are balanced, readable, entertaining and honest. It's really nice that people such as yourself take the time and trouble to give great peer insights into gear that reviews sites don't even touch upon. Love your work.

I have never heard a Perreaux product that I liked, but that's incidental and a lot of what you have written is easily reconcilable to my own experiences with the brand,albeit that your reactions to those characteristics are far more positive than my own and IMHO your emote summary is generous and forgiving.

 

Thanks again for the ongoing and wonderful contributions to the forum, it helps give this place some magic