Most transparent amps under 10k??

One reason why the output impedance spec is important. Most amps these days are voltage-drive and as such I can't agree that the response changes "substantially" with the load.

As you say this is not the case so much with valve amps, but then who would want one of those? Ahh, someone who likes some colouration in the sound!

 

I have seen a range of frequency responses of various amplifiers in to simulated speaker load.These were posted on an Australian forum.People could not tell the SS amps from the valve ones and they all showed far from flat responses.Indeed some self declared experts picked out one of the SS amps as "obviously a valve amp".

 

That should be your signature Rob.

 

"we do not believe that all amps sound the same"...untill they cost £500, then they all sound the same?

Is that right?

 

uch

To be fair Mark, there is more than a subtle difference between "all competently designed amps should sound the same working within certain parameters"(*) and "all amps sound the same".

* I can't remember the exact words used, but you get the point.

 

amps and speakers need that synergy, but my view is that speakers live with you the most of your life , as for electronics you will change more often untill you find that fulcrom.

 

Sounds like an unusual mix of amps was used. As I said, most SS amps won't change their response substantially with load variations typical of a speaker.

A very quick Google found this:


Vandersteen 2Ce, frequency response at 10mW at speaker terminals driven by (from top to bottom at 20kHz): Hafler 9500, Aragon 4004 Mk.II, Melos 400 (4 ohm tap), and Sonic Frontiers SFS-80 amplifiers (1dB/vertical div.).

http://www.stereophile.com/reference/810

 

Moderator Message:

Advertise in the Trade forum please Nando.

 

Yes, and that has always been the overwhelming view of those on the so called objectivist wing. I honestly don't know anybody ever claiming that all amps sound the same.

As for the £500 figure, that is simply a budget indicator at which point there is simply no excuse for getting things wrong.
For an example of what is possible today for £500 (new) go look at the Cambridge 740A.

 

IMO CA 740 is not transparent amp it's very muddy.

 

It is transparent, you just don't like that sound.

 

I'm curious from a "minimum requirements" perspective.
If we work on the logic that amps do the sound the same, assuming that they meet minimum standards, then what amp would you suggest would be the the starting point for that minimum?
Are you talking about say a CA640? If so, maybe I'll try demo'ing one at home.

 

All amps sound the same so why bother, they are all perfect, anything you hear is all in your mind, etc etc, ad infinitum.

 

hehe
It is not that I don't like it. It is not good enough for me. It might be transparent enough for you...

 

What is your criteria for it not being 'good enough'? I have to assume you didn't like the sound in some way. Do you have evidence to show that the output doesn't follow the input signal as closely as another amp? It is easy enough to find evidence to show that it does.

 

Another one who can't or won't read

No they don't.

No they aren't.

Yes it often is, if you insist on basing decisions on sloppy uncontrolled dems.

Absolutely - seems to be working judging by the threads I'm seeing on forums recently.

 

640 would do it - and certainly enough power for your speakers

740 looks nicer and better outer build.

 

There are many criterias. Some amps are muddy and changing them is like opening a curtain, removing noise... The "picture" gets clearer, musicians more palpable, there is air around musicians instead of noisy 2D soundstage. I heard CA on KEF Reference speakers (dont remember the model) and it was not very good. I don't have any evidence, I just listen. I don't hear differences worth mentioning between cables but I do between amps. And once I hear something good something else is not good enough any more.

 

Far enough. I only take exception with the term transparent as to my mind it can be accurately defined. Good is a personal preference though.

 

IIRC the Cambridge 640 is based on an IC chip amp; the 740 / 840 are not.

NB chip amps can have their own particular issues beyond the control of implementation - usu. related to excess noise, internal crosstalk (both thermal and electrical) and (sadly, for many) really, really invasive current-limiting.

IME - I could find ways around the noise /poor gain structure issues (e.g. operate in inverting mode, at desired low forward gain then apply separate noise gain compensation) but the onboard protective measures when I last bothered were always a horrible, hard, early limit on performance. No doubt there are more modern and better IC amps available now