Audible benefit from higher 'headroom.'

[GeneZ]

I being a novice, have a question in regards to the benefits to adding higher headroom and lower noise into a circuit.

Hypothetically..

Preamp A. It was considered a very good unit on the day it was released. Audiophiles heaped praises on it.

Then a few years passed... Now the same manufacturer produces Preamp A.2. The literature states that the new rendition has better components that produces higher headroom and lower noise.

If all other aspects remain equal? What differences might one hear with the lower noise and higher headroom?

Gene

[nigelwright7557]

You will get a better transient response (high peaks in the sound)

I made the mistake with my first amp design of having low power supply rails.
Before the amp could give out full power the transients were well and truly clipped.

[AndrewT]

I generally aim for >=+20dB of headroom in my system.
Many Members rubbished this idea saying it is a complete waste of resources.

If I want to listen at 1W into 88dB/W @ 1m speakers then I use a 100W amplifier. For half a watt of average listening power, 50W amp power is generally adequate.
If that 1watt is a signal voltage of 150mVpk, I would aim for a signal handling capability before the power amp of >+30dB, i.e. >4.5Vpeak and preferably ~15Vpk.

I do believe I can hear the improvement in sound quality when adequate overhead is built into the system. One example is that I am listening to a nice sound system playing clean and energetically and someone knocks at the door. I have to turn down the stereo to hear what they have to say. The system does not sound loud, it just sounds nice because the peaks are not being clipped nor limited.
A 68W 3886 chipamp cannot play as clean as a well designed 50W discrete amp when the level exceeds little more than background level.
I am listening as I type to a 3886 chipamp on +-30Vdc supplies and the average level is 400mVac to 600mVac at the speaker terminals. The voltage overhead in the chipamp is ~+34db. I know if I turn the volume up it will not sound as nice. The output gets clipped. It cannot play energetically.

[DF96]

It depends on how near the limits you were. If your signal level was a bit high so you were getting occasional clipping then you will get less. If, on the other hand, your signal level was a bit low so you had some noise you will now get less noise. You are unlikely to get both benefits, unless the old preamp wasn't very good. More headroom and less noise makes a preamp more versatile, but if the old preamp was being used right in the middle of its range (so no noise, no clipping) then the new one will not give any improvement.

[Nico Ras]

I concur with AndrewT, the higher the power available the better it sounds at normal volume levels.

[sreten]

Hi,

A preamp either has enough headroom or it doesn't. If it does have enough
than adding more will do very little. Same with noise, if its very good in
the first place making it lower will do very little.

rgds, sreten.

[EWorkshop1708]

Headroom is good.

I remember when I did audio for a church when I was 16, how I'd notice when the mixer board was being used, and it was being clipped on a channel, you did not hear the distortion until you made the level significantly higher. Of course I turned it down to the proper level and got the clipping light to turn off, but it explains how much extra headroom is good.

I just wish some opamps really took more than the recommended +/- 15V. I know some do +/-22V but that's not much higher, because for SOA purposes, you will still keep the voltage lower some.

[sakis]

isnt this what always the Japanese comercial designers did ? 56 +56 volts of rails ,just a pair of outputs , good quality of front end , and then a VI limiter to avoid cost of overdesign ( IE more outputs ,more supply etc. ) Just in case the machine is used for a party ...

in "normal " listening levels will play perfectly

[stratus46]

Headroom is far more important when recording 'live' with microphones where anything an happen. When coming off a CD you know absolutely what the maximum level can be. That's why it's perfectly fine to connect a CD line out to a PC input. Most PC inputs can handle 5 Volt p-p or less which is more than the CD puts out so there's no problem.

If you're not noticing any noise issues you're not likely to notice anything significant. BUT there are some who just have to have the newest and that's fine. It usually puts some nice used gear on eBay.

G²

[a.wayne]

Originally Posted by AndrewT

I generally aim for >=+20dB of headroom in my system.
Many Members rubbished this idea saying it is a complete waste of resources.

If I want to listen at 1W into 88dB/W @ 1m speakers then I use a 100W amplifier. For half a watt of average listening power, 50W amp power is generally adequate.
If that 1watt is a signal voltage of 150mVpk, I would aim for a signal handling capability before the power amp of >+30dB, i.e. >4.5Vpeak and preferably ~15Vpk.

I do believe I can hear the improvement in sound quality when adequate overhead is built into the system. One example is that I am listening to a nice sound system playing clean and energetically and someone knocks at the door. I have to turn down the stereo to hear what they have to say. The system does not sound loud, it just sounds nice because the peaks are not being clipped nor limited.
A 68W 3886 chipamp cannot play as clean as a well designed 50W discrete amp when the level exceeds little more than background level.
I am listening as I type to a 3886 chipamp on +-30Vdc supplies and the average level is 400mVac to 600mVac at the speaker terminals. The voltage overhead in the chipamp is ~+34db. I know if I turn the volume up it will not sound as nice. The output gets clipped. It cannot play energetically.

+10 ..................