Question Amplifier review terminology help

[Ren]

I'm brand new to this forum, so I fear I may be treading on well trod ground. However, I read a lot of the terrific reviews for amplifiers, and I read the wonderful terms for how the amplifier sounds, which I love, but I can't truthfully understand (hand on heart). For example: "Unfussy musical character" and "Struggles with timing" or "Sound lacks scale".

So, with a "fussy musical character" that's detectably "fussy", what is the specification of that amp, that makes it "fussy"? If this was known, or could be known, then it would be really, really useful.

I'm trying to get to a point where I can see if (for example) a 0.005% THD+N @ 1 kHz, 50 W, 500 Damping factor, 120 dB SNR-W. 10 Hz to 30 kHz Amplifier is going to sound "fussy" and/or would struggle with "timing".

Thanks ~Ren.

 

[12th Monkey]

Fussy isn't a very helpful term. The user may mean it doesn't work well with other kit with certain characteristics, in which case saying so would seem more useful.

Scale could refer to a large soundstage, or that it lacks the lower-level oomph to sound convincing.

Timing is a harder one, though to me it means it means the tautness with bass and percussion that makes the foot tap and the head nod.

 

[Adam W.]

I think technical specifications are largely irrelevant as far as sound goes. They don't really give an idea of how the amp will actually sound or perform. The only thing that will do that is your ears.

If you compare two amps side by side you might prefer the sound of the amp with lower specifications.

Some people will tell you that all amps sound the same and only loudspeakers make a difference. I don't think thst is true.

I own a Cambridge CXA81 but have recently been demoing an Arcam SA20 with a friend using the same speakers (Wharfedale 11.4s).

The Arcam certainly does sound different. It is noticably smoother and has a fuller, warmer character that is much less fatiguing. It also sounds better with a wider variety of music.

I'm actually going to send my CXA81 back and get myself an SA20!

 

[Deleted member 188516]

I think technical specifications are largely irrelevant as far as sound goes. They don't really give an idea of how the amp will actually sound or perform. The only thing that will do that is your ears.

If you compare two amps side by side you might prefer the sound of the amp with lower specifications.

Some people will tell you that all amps sound the same and only loudspeakers make a difference. I don't think thst is true.

I own a Cambridge CXA81 but have recently been demoing an Arcam SA20 with a friend using the same speakers (Wharfedale 11.4s).

The Arcam certainly does sound different. It is noticably smoother and has a fuller, warmer character that is much less fatiguing. It also sounds better with a wider variety of music.

I'm actually going to send my CXA81 back and get myself an SA20!

exactly !

at some point you have to just ignore specs / measurements and just trust your ears and listen.

 

[matthewpiano]

If it all came down to specs this whole hi-fi malarky would be much easier, but it doesn't.

As @Adam W. says, it's how you hear the music of your choice through a system that is the final judgement. Hi-fi is about having a system that brings you maximum enjoyment from your music, whatever that means the equipment has to bring to the party. Science is a huge help to manufacturers in achieving good engineering practise, but it isn't the last word.

The general subjectivity of hi-fi makes reviews difficult, and some of the more elaborate descriptions of sound can confuse things further. This is why auditioning is the only safe way of choosing hi-fi, and why auditioning in your own home beyond the standard 30-60 minute blast at the dealer's is the only way to be completely sure.

 

[Ren]

I agree with you Adam W, that it's down to preference - I'll always use a little tone control if one is fitted - especially the +bass.

The SA20 is class A (in part) with 0.003% THD at 1 kHz (which means not any noticeable, nice 2nd order harmonics). I can't find the THD for the CXA81 - but it's class AB - so, it could have bad THD at say 20 Hz or 10 kHz, which may be the reason. I don't know. ~Ren.

 

[12th Monkey]

What gear are you looking at/for?

 

[Ren]

What gear are you looking at/for?

Hi 12th Monkey - I'm designing and making an amplifier (for my own use), after 10 years of tolerating two-way active speakers, which are annoying. I want to avoid it being 'fussy' or to have 'timing' issues - if I knew what they were (in technical terms).

~Ren.

 

[Greenwich_Man]

Hi Ren

I love my Arcam SA20. Just go and have a listen and trust you ears.

 

[12th Monkey]

Hi 12th Monkey - I'm designing and making an amplifier (for my own use), after 10 years of tolerating two-way active speakers, which are annoying. I want to avoid it being 'fussy' or to have 'timing' issues - if I knew what they were (in technical terms).

~Ren.

Sounds like a more drastic solution than I'd entertain, but the very best of luck! (I doubt you can distil those descriptions into a spec sheet, though.)

 

[nopiano]

I want to avoid it being 'fussy' or to have 'timing' issues - if I knew what they were (in technical terms).

Welcome, Ren! I don’t think you’ll find any technical terms that correspond to these subjective interpretations, and if there were any then all WHF - and other mags - would need to do is reprint the manufacturers spec, or even test the kit themselves.

You might find obvious extremes, like excessive THD in an amp would probably sound harsh or gritty, for example. Even if you listened to dozens of amps I doubt you’d find any consistency. These descriptors are as informative as it gets, unless you prefer both measurements and listening, in which case Hi-Fi News and Stereophile and likely to appeal. They do to me.

All you can do - and hats off for your building skills - is be thorough and careful in construction and hope you like the outcome.

 

[Gray]

Some people will tell you that all amps sound the same and only loudspeakers make a difference. I don't think thst is true.

When challenged, I've seen such people subsequently qualify the statement by stating that 'all well-designed amps sound similar'
But I don't agree with that either. Some might, but many sound significantly different (with identical source and speakers).

 

[abacus]

All amps sound the same if they are well designed and not overdriven into a resistive speaker load, however there is no such thing as a resistive speaker load as all speakers contain capacitance and inductance as well, (Which also varies with volume and frequency) how the amp reacts to this is what makes 2 well designed amps sound different. (If you swapped your speakers you could quite easily find that the Cambridge was smother than the Arcam due to how they react with the change in speakers)

Technical results are vitally important when testing and reviewing as they can indicate if the manufacture has tried to pull a fast one so that its characteristics match certain speakers (Which they probably have some connection with) rather than being neutral. (Most engineers would just call it a poor design)

It all comes down to the synergy of the complete system and your personal preferences; hence you must always try the combination before you buy.

Bill

 

[Ren]

All amps sound the same if they are well designed and not overdriven into a resistive speaker load, however there is no such thing as a resistive speaker load as all speakers contain capacitance and inductance as well, (Which also varies with volume and frequency) how the amp reacts to this is what makes 2 well designed amps sound different.
Bill

That is an encouraging statement Bill.

 

[Adam W.]

The Arcam immediately sounded different to my ears. To be honest, I was expecting it to sound pretty much the same but it doesn't.

The biggest differences appear to be that it sounds smoother, fuller and warmer with less forward highs. The highs sound much more pleasant and natural to my ears. It almost sounds like it's going to reproduce less detail but the opposite is true. It sounds clearer and less distorted.

Don't get me wrong, I do miss the more instantly gratifying sound of the Cambridge and what it has to offer, but the Arcam is just more pleasing in the long run and easier to listen to.

I can listen to poorly recorded/mastered music with the Arcam as it seems to be more forgiving of it. The Cambridge made a lot of such music unlistenable for me and I found myself avoiding music I actually like.

As was pointed out, the SA20 operates in pure class A to a point.

Could that explain much if the difference?

 

[Al ears]

The Arcam immediately sounded different to my ears. To be honest, I was expecting it to sound pretty much the same but it doesn't.

The biggest differences appear to be that it sounds smoother, fuller and warmer with less forward highs. The highs sound much more pleasant and natural to my ears. It almost sounds like it's going to reproduce less detail but the opposite is true. It sounds clearer and less distorted.

Don't get me wrong, I do miss the more instantly gratifying sound of the Cambridge and what it has to offer, but the Arcam is just more pleasing in the long run and easier to listen to.

I can listen to poorly recorded/mastered music with the Arcam as it seems to be more forgiving of it. The Cambridge made a lot of such music unlistenable for me and I found myself avoiding music I actually like.

As was pointed out, the SA20 operates in pure class A to a point.

Could that explain much if the difference?

Surely all Class A/B amps operate as as Class A up to a point.....

 

[Adam W.]

Surely all Class A/B amps operate as as Class A up to a point.....

I looked into it and it's confusing.

 

[Ren]

Surely all Class A/B amps operate as as Class A up to a point.....

Yes Al ears, that is correct - it's the reason that some class AB amplifiers run 'warm' with nothing going through - the warmer they are (i.e. the greater the bias), the more they operate in class A - well, class AA in that sense. ~Ren.

PS - my headphone amplifier runs as a class AA at all levels, and I'm really pleased with that part so far - but I did kill my Audio Technica headphones when testing.

 

[Al ears]

Yes Al ears, that is correct - it's the reason that some class AB amplifiers run 'warm' with nothing going through - the warmer they are (i.e. the greater the bias), the more they operate in class A - well, class AA in that sense. ~Ren.

PS - my headphone amplifier runs as a class AA at all levels, and I'm really pleased with that part so far - but I did kill my Audio Technica headphones when testing.

Oops, sorry for your loss.....

 

[Adam W.]

So what exactly is the difference between class AB and Arcam's class G? Arcam appears to use the operating in pure class A as a selling point.

 

[Ren]

Oops, sorry for your loss.....

It's okay Al ears - a quick look through WHAT HI*FI and I've ordered some AKGs.

 

[Ren]

So what exactly is the difference between class AB and Arcam's class G? Arcam appears to use the operating in pure class A as a selling point.

Hi Adam W - I have this strange feeling that because the Class G is more efficient (over Class AB), for the same heatsink size, you could run a Class G in a Class A mode if you wanted to. I could be wrong. This is suggesting that Acram could be relying on a little Class A distortion, which can sound nice, or achieving very low distortion levels from 20 Hz to 20 kHz at say 0.1 Watt to 50 Watts - which also sounds nice. ~Ren.

 

[Greenwich_Man]

The Arcam SA20 sounds more in the room, than other amps. The SA20 puts the sound there. Just have a listen to it. And compare.