[CButterworth]

I have just completed the Aspen AKSA 55 and like it.  My only previous high quality amp was an Arcam Alpha.  Now, I've read discussions about people being able to hear when an amp causes clipping.  How do you recognize this?  What does clipping sound like?

I remember when I played a good quality recording of Bach's Brandenburgs on my Arcam.  The strings sounded strong, it almost felt as if I could hear the sound of rosin on the individual strings as there was some roughness to the sound - at least this is what I took it for ie. a good sound reproduction of a good recording.  However, I also noticed the same effect on some vocal tracks.

Is this the sound of clipping? So far, I have not heard this on the AKSA.

Also, what is the best way to critically listen to sound equipment?  What muical qualities should I be listening for?  Obviously, if I enjoy the music then that is foremost.

Thanks,
Charlie

[_scotty_]

Charlie,The roughness you heard may or may not have been clipping depending on how loud you were playing your system.It could just as easily been your loudspeakers protesting because you were asking them to play too loud. You haven't told us how loud you were playing the system when this happened.A Radio Shack db meter is handy for measuring this.  
Which amp sounds more real on un-amplified acoustic music.
Real instruments are not always pleasant sounding. I look for the largest sounding acoustic space with the tightest focus of the sound source in the that space as well as the greatest possible separation of sound sources. Front to back layering in the sound stage should be easy to hear and the image should project out into the room towards the listener at times as well as extending backwards toward infinity.No distortion of the sound stage should be present. On appropriately recorded material the you should hear multichannel effects, ie sounds should come from beside you,above you and behind you. These should sound sharply focused, total immersion in a spacial or acoustic enviroments is also possible from some recordings.
I should be able to follow any instruments part in an orchestra if the recording is good. There should also be no clue as to how much power is availible, the system should sound completely effortless,regardless of how loud it is playing. You should have the impression of infinite power being availible to do the job. No dynamic compression should be happening either. I also don't listen to how well a system does a particular instrument  or vocal, I listen to how it does everything at once. I don't listen to music in 30second chunks. This is some of the criteria I use to evaluate power amps as well as systems in general.  Hope this was helpful, Scotty

[CButterworth]

Scotty,

Thank-you for the reply.  When I used the Arcam, I had the volume relatively low (no more than 9 O'Clock).  I was also using decent speakers (although I cannot remember their brand).

My current system uses my new AKSA 55 and some cheap, but recommended Sony 3-way 100W speakers (from BestBuy).  I know that these are not even close to high-end speakers, but having spent a small bundle on the amp, I now have to save for better speakers.  I built a passive preamp using an Elma switch and Alps Blue-velvet 50K pot and don't need to increase the volume beyond about 9 O'Clock.  Anyway, I'll listen to the same track on my new amp this evening and see if I can detect what I think is clipping.

My guess is that the best way to critically listen to an amp is with eyes closed and trying to pinpoint the position of various instruments.  Compared to my cheap WalMart (now trashed) player, when I played a Michael Hedges track, the vocals sounded as if the singer were in the same room as me - something that really surprised me.

Regards,
Charlie