The problem with volume controls

I just had a thought.

I have an annoying problem with my volume control. When I push the volume above 9'oclock the sound is SO loud it becomes unlistenable.

Then I had a thought; ok mine might be the worst; but I have never found a single hifi where the right hand side of the control is useable. I used the right hand side of my dads hifi a few years back at a party, I melted the voice coils on a pair of Willison Benesch ACTIIs.

So my query is this, does anyone actually use most of there volume control?

if not where does the fault lie?

 

On my passive pre I can use the full range of the volume control. Full volume is unity gain which is VERY loud but I do use it for some classical recordings.

IMO the fault lies with pre-amp design. Actual gain in the pre-amp is rarely a requirement these days.

Michael.

 

In my experience it tends to be less of a problem for amps with digital volume controls - they seem to stay linear over a much greater range.

Given that CD has been around over 20 years, you'd think amp designers would have designed their amps to cope with the generally high output from players by now!

 

On my old preamp 80% is 'unity' from the line inputs. So there's margin for low output sources or insensitive power amps. FWIW I think some gain and a buffer in the output is good practice.

Paul

 

I voted for CDP outputs being too high.

In theory the line level between components should be 775mV (0dBu) RMS.

However, the "standard" in CD players is for 2V RMS. Obviously this is quite a lot louder (about +8 dBu).

The problem comes in that people sometimes buy CD players on the basis of A/B dems, leaving the amplifier volume level set the same for all players. What tends to happen is that the loudest one wins because of the dynamic range advantage of a louder sound. So although this nominal 2V standard exists, most manufacturers push it higher, even as high as 3V rms (nearly +12dBu).

So it comes to the point that for most listening the system amplifier needs to have a voltage gain not much in excess of unity (as 2.83Vrms is 1W into 8 ohms). That includes the power amp with a typical gain of +20 to +30 dB, so the pre-amp needs to provide between 10 to 20dB of attenuation for a typical listening level.

Since the pre must also be able to provide gain for "quieter" components, the pre-amp must range from mute (minus infinity dB) to around +20 dB gain or more.

This is then compounded by a standard pot being linear in terms of voltage gain with position. Which means it is non-linear with regard to dB gain, so seems to get louder very quickly at the bottom end of its range, and doesn't add much at the top end of its range.

 

Hi,

The answer is of course:

"NOBODY expects the Spanish Inquisition! Our chief weapon is surprise...surprise and fear...fear and surprise.... Our two weapons are fear and surprise...and ruthless efficiency.... Our *three* weapons are fear, surprise, and ruthless efficiency...and an almost fanatical devotion to the Pope.... Our *four*...no... *Amongst* our weapons.... Amongst our weaponry...are such elements as fear, surprise.... I'll come in again."

I use very much the whole range, I use a passive preamp which in turn uses an attenuator transformer.

The fault if you cannot use the entire volume control range is poor gainmatching structure in the system. This usually results in excessive noise and distortion, on top of the "9 O'Clock is TOO BLOODY LOUD syndrom. Adding in-line attenuators does not really address this all that well, but may be a last resort.

Ciao T

 

I was hoping for a Monty Python reference.
I do happen to notice that the only people who use their entire range use passive preamps.

My hopeful solution is getting my CD player modified to have a lower output lvl.

 

I've gone for the pre-amp design.

A while ago I bought some of attenuaters to try them out. This knocked 10db off the cd input.

It did allow me to use more of the volume pot but robbed the music of all vitality in my system. I sold them and haven't worried about it since.

However, Peter, it may be worth you getting a pair to try out if you have trouble going any further than 9 'o' clock. I had the Rothwells and I think they cost me £40 (ish), and ithey sold very quickly so you could get most of your money back if you don't like them.

 

exactly my experience too.... total music killers.

 

I guess it is not to great a problem, it is just fustrating that all my HTPC requires a volume of about 12'oclock when my cd goes around 9'oclock when i listen (I do listen loud).

I just occasionally forget to check the volume when i switch from HTPC to CD.

Last time it happened it was nicely timed with my wife walking back from work. She said she could hear what song I was playing from the bridge. For anyone who lives in York I live next to the Sorting office and it was Lendal bridge. for anyone who doesnt know there is a park inbetween; LOUD!

If attenuators kill the music I don't think I will be heading that route. I can only assume that my CD can be modded.

 

I'd like to know what you have against the Vikings, who operated true socialist wealth-redistribution policies, gave your northern territories many wonderful place-names and, contrary to popular opinion, preferred Isobaldriks to horns