Digital vs Analog Volume Control

[andyjm]

Thank you. This is all new to me, I'm still understanding everything. I really appreciate your help and info

If you have time and want to experiment, there are software packages (Foobar I believe is one) that will allow you to take a 24/96 file and reduce it to 16/44.1 - you can then compare the 'normal res' file with a 'hi res' file being sure that they both came from the same source. Much (if not all) of the differences that have been described with hires when compared to normal CD quality can be traced back to different masters and different levels of eq/compression used when producing the discs / files - and not due to the format difference. There are good maths and physiology reasons why 16/44.1 is good enough.

Foobar will also allow you to randomly A/B compare, so that you can test yourself blind.

 

[MajorFubar]

Just to further underline what Andy and Dave have said (because sometimes common sense needs all the publicity it can get), in a final master, there's nothing about a 24 bit / 96kHz (etc) master which will intrinsically make it sound better than 16/44.1. If you take a hi-res master and resample it to 16/44 you will not hear any difference. Any audible differences between SD and HD releases of the 'same' album are always because they're really not the same master at all.

 

[unsleepable]

High bit depth is used in DSP processing to avoid truncation and lack of precision due to integer maths. Taking a 16 bit sample, doing calcs at 32 or 64 bits and then reducing the result back to 16 bits for output to a DAC does not involve 'chopping off bits' in the sense that any of the precision in the original 16 bits is lost.

That is true when altering the signal. The same way 24-bit is used in studios for mixing to keep noise level out of the audible range.

But digital volume attenuation is simply making the floating point numbers smaller. Then you can't just chop the bits where you have moved the signal to.

 

[unsleepable]

I think I'm just going to bite the bullet and buy the power amp, using SM6 as a pre.

And there are also the upsides. You are removing an analogue stage from the signal path—and since you will use the streamer as a source anyways, no preamp will be better than the best of preamps. Noise will be lower, same as crossover. Digital volume controls don't deteriorate with time, and don't have balance issues…

 

[davedotco]

I think I'm just going to bite the bullet and buy the power amp, using SM6 as a pre.

And there are also the upsides. You are removing an analogue stage from the signal path—and since you will use the streamer as a source anyways, no preamp will be better than the best of preamps. Noise will be lower, same as crossover. Digital volume controls don't deteriorate with time, and don't have balance issues…

Ok.

Try and get an agreement with Richers to swap it for the integrated if it doesn't work out. The sensitivity match looks good so you should be fine, but just in case.......*unknw*

 

[matt49]

Just to further underline what Andy and Dave have said (because sometimes common sense needs all the publicity it can get), in a final master, there's nothing about a 24 bit / 96kHz (etc) master which will intrinsically make it sound better than 16/44.1. If you take a hi-res master and resample it to 16/44 you will not hear any difference. Any audible differences between SD and HD releases of the 'same' album are always because they're really not the same master at all.

There is even a view in some quarters that hi-res files can sound worse (more distorted) than 16/44 files.

This requires a bit of explanation, and I’m afraid I’m a little fuzzy on the science, but thankfully you’ll have an actual physicist to help you later on.

First, we’ll assume that in some circumstances people can hear differences between hi-res and 16/44 files in DB ABX tests. This will be a deal-breaker for some people, but I’m pretty confident it’s the case. Back in July, Scott Wilkinson launched a trial of hi-res vs 16/44 over on the AVS forum. I’ve done the test using the foobar 2000 ABX plug-in, and I was able to discriminate with ease. Others have also done it.

The question is: why? I’m not inclined to believe any of the explanations offered by advocates of hi-res audio, viz. that frequencies above 20kHz cause intermodulation harmonics in the audible range, or that binaural hearing (localization) depends upon hairs in the ear canal picking up frequencies above 20kHz.

The most plausible explanation, it seems to me, is that the extra HF energy in hi-res files is overtaxing the replay equipment, especially amplification, and that this causes intermodulation distortion below 20kHz. This explanation has been proposed by physicist David Griesinger: http://www.davidgriesinger.com/intermod.ppt.

One reason I'm inclined to follow Griesinger's hypothesis is that when I successfully distinguished between the hi-res and 16/44 files, I actually preferred the latter. It seemed to me that the hi-res versions had some audible HF distortion.

Matt

 

[Obagleyfreer]

I think I'm just going to bite the bullet and buy the power amp, using SM6 as a pre.?

And there are also the upsides. You are removing an analogue stage from the signal path—and since you will use the streamer as a source anyways, no preamp will be better than the best of preamps. Noise will be lower, same as crossover. Digital volume controls don't deteriorate with time, and don't have balance issues…

Ok.

Try and get an agreement with Richers to swap it for the integrated if it doesn't work out. The sensitivity match looks good so you should be fine, but just in case.......*unknw*

Only one problem with that, I'm living in New Zealand. I do have a good HiFi store near me but they have very limited stock, hence me not being able to demo the power amp.
I'm sure if it was really terrible then they would let me change it. From what you're all saying though it sounds like it will all be fine and I'm worrying about nothing. This is my first step into the HiFi world and while these are cheap units in HiFi terms, for me it is a fair amount of money.

 

[Obagleyfreer]

I think I'm just going to bite the bullet and buy the power amp, using SM6 as a pre.?

And there are also the upsides. You are removing an analogue stage from the signal path—and since you will use the streamer as a source anyways, no preamp will be better than the best of preamps. Noise will be lower, same as crossover. Digital volume controls don't deteriorate with time, and don't have balance issues…

Ok.

Try and get an agreement with Richers to swap it for the integrated if it doesn't work out. The sensitivity match looks good so you should be fine, but just in case.......*unknw*

Only one problem with that, I'm living in New Zealand. I do have a good HiFi store near me but they have very limited stock, hence me not being able to demo the power amp.
I'm sure if it was really terrible then they would let me change it. From what you're all saying though it sounds like it will all be fine and I'm worrying about nothing. This is my first step into the HiFi world and while these are cheap units in HiFi terms, for me it is a fair amount of money.

 

[Obagleyfreer]

Just to further underline what Andy and Dave have said (because sometimes common sense needs all the publicity it can get), in a final master, there's nothing about a 24 bit / 96kHz (etc) master which will intrinsically make it sound better than 16/44.1. If you take a hi-res master and resample it to 16/44 you will not hear any difference. Any audible differences between SD and HD releases of the 'same' album are always because they're really not the same master at all.

There is even a view in some quarters that hi-res files can sound worse (more distorted) than 16/44 files.

This requires a bit of explanation, and I’m afraid I’m a little fuzzy on the science, but thankfully you’ll have an actual physicist to help you later on.?

First, we’ll assume that in some circumstances people can hear differences between hi-res and 16/44 files in DB ABX tests. This will be a deal-breaker for some people, but I’m pretty confident it’s the case. Back in July, Scott Wilkinson launched a trial of hi-res vs 16/44 over on the AVS forum. I’ve done the test using the foobar 2000 ABX plug-in, and I was able to discriminate with ease. Others have also done it.

The question is: why? I’m not inclined to believe any of the explanations offered by advocates of hi-res audio, viz. that frequencies above 20kHz cause intermodulation harmonics in the audible range, or that binaural hearing (localization) depends upon hairs in the ear canal picking up frequencies above 20kHz.

The most plausible explanation, it seems to me, is that the extra HF energy in hi-res files is overtaxing the replay equipment, especially amplification, and that this causes intermodulation distortion below 20kHz. This explanation has been proposed by physicist David Griesinger: http://www.davidgriesinger.com/intermod.ppt.

One reason I'm inclined to follow Griesinger's hypothesis is that when I successfully distinguished between the hi-res and 16/44 files, I actually preferred the latter. It seemed to me that the hi-res versions had some audible HF distortion.

Matt

Thanks Matt.
I'll have a play with Foobar2000, sounds really interesting.
I'm in the Graphics/imaging industry and this all sounds similar to 8bit vs 16bit image files. Between the 2 there is very little difference to the eye. The human eye can't actually see much past an 8bit file anyway, and certainly can't take in 16bits of info. Maybe it's the same with our ears, there's only so much information the ear and brain can take in and process.
I feel silly worrying about such a small thing as digital volume control on what is really a very entry level set up!
Thanks for your input.

 

[Overdose]

I feel silly worrying about such a small thing as digital volume control on what is really a very entry level set up! Thanks for your input.

It's your money and not an insubstantial sum, so you have every right to find out your answers by asking as many questions makes you feel comfortable.

If you seek out the facts and learn about the way things actually work, as opposed to how some imagine things to, you will see for yourself just how much or little you need to spend to get the best results.

 

[Obagleyfreer]

Yes this is true. I always seem to thoroughly research products before buying and sometimes it's a curse. It might be better to be ignorant and just enjoy what end up with. There's always better.
Anyway, I had a chat with my local hi fi store and they are happy to use the 651W that I ordered as a demo so I can listen to both with my stream magic. It won't be with my speakers, in my home but at least I'll get an idea of the sonic differences between the 2, hopefully.

 

[davedotco]

Yes this is true. I always seem to thoroughly research products before buying and sometimes it's a curse. It might be better to be ignorant and just enjoy what end up with. There's always better. Anyway, I had a chat with my local hi fi store and they are happy to use the 651W that I ordered as a demo so I can listen to both with my stream magic. It won't be with my speakers, in my home but at least I'll get an idea of the sonic differences between the 2, hopefully.

I doubt there will be any sound quality issues, it is primarily about the functionality, just make sure the volume control works nicely and that it sounds good at the lowest volume settings, it is at these levels that any issue will show up.

 

[Obagleyfreer]

Yes this is true. I always seem to thoroughly research products before buying and sometimes it's a curse. It might be better to be ignorant and just enjoy what end up with. There's always better. Anyway, I had a chat with my local hi fi store and they are happy to use the 651W that I ordered as a demo so I can listen to both with my stream magic. It won't be with my speakers, in my home but at least I'll get an idea of the sonic differences between the 2, hopefully.

I doubt there will be any sound quality issues, it is primarily about the functionality, just make sure the volume control works nicely and that it sounds good at the lowest volume settings, it is at these levels that any issue will show up.

I went for the shoot out today between the 2 amps. The integrated amp using SM6 as source sounded warmer, and, to me more pleasing.
The Power amp, using SM6 as digital preamp, sounded less warm but had much more detail and was more dynamic, also better timing.
Personally I preferred the warmer sound of the integrated, but the salesman said the power amp will warm up as its run in and only sounded that way because it was fresh out of the box, unlike the integrated that was their demo and has had hours and hours of play time.

 

[davedotco]

Yes this is true. I always seem to thoroughly research products before buying and sometimes it's a curse. It might be better to be ignorant and just enjoy what end up with. There's always better. Anyway, I had a chat with my local hi fi store and they are happy to use the 651W that I ordered as a demo so I can listen to both with my stream magic. It won't be with my speakers, in my home but at least I'll get an idea of the sonic differences between the 2, hopefully.

I doubt there will be any sound quality issues, it is primarily about the functionality, just make sure the volume control works nicely and that it sounds good at the lowest volume settings, it is at these levels that any issue will show up.

I went for the shoot out today between the 2 amps. The integrated amp using SM6 as source sounded warmer, and, to me more pleasing. The Power amp, using SM6 as digital preamp, sounded less warm but had much more detail and was more dynamic, also better timing. Personally I preferred the warmer sound of the integrated, but the salesman said the power amp will warm up as its run in and only sounded that way because it was fresh out of the box, unlike the integrated that was their demo and has had hours and hours of play time.

Amplifiers need to be at optimum temperature, from new this may take a day or two. After that most of the changes will be you as you adapt to the sound.

The pre-amp (section in the integrated) will be causing the extra warmth, my personal experience is that 'warmer' is not so good long term, but that is hugely personal, i think almost all amplifier/systems are too warm, but thats me.

Try and give it another go after a day or two, then decide.

 

[Obagleyfreer]

Yes this is true. I always seem to thoroughly research products before buying and sometimes it's a curse. It might be better to be ignorant and just enjoy what end up with. There's always better. Anyway, I had a chat with my local hi fi store and they are happy to use the 651W that I ordered as a demo so I can listen to both with my stream magic. It won't be with my speakers, in my home but at least I'll get an idea of the sonic differences between the 2, hopefully.

I doubt there will be any sound quality issues, it is primarily about the functionality, just make sure the volume control works nicely and that it sounds good at the lowest volume settings, it is at these levels that any issue will show up.

I went for the shoot out today between the 2 amps. The integrated amp using SM6 as source sounded warmer, and, to me more pleasing. The Power amp, using SM6 as digital preamp, sounded less warm but had much more detail and was more dynamic, also better timing. Personally I preferred the warmer sound of the integrated, but the salesman said the power amp will warm up as its run in and only sounded that way because it was fresh out of the box, unlike the integrated that was their demo and has had hours and hours of play time.

Amplifiers need to be at optimum temperature, from new this may take a day or two. After that most of the changes will be you as you adapt to the sound.

The pre-amp (section in the integrated) will be causing the extra warmth, my personal experience is that 'warmer' is not so good long term, but that is hugely personal, i think almost all amplifier/systems are too warm, but thats me.

Try and give it another go after a day or two, then decide.

Thanks for the advice
On the box of the power amp
it says to run the amp for a constant 36 hours before use. Does this mean just have it on? Or do I need to be playing music for 36 hours?
Sorry if that's a silly question! Obviously I don't want to be playing music for 36 hours straight, so could I just not plug the speakers in and have it playing music? Or will the fact there's an open circuit do damage? I know this was a no no for tube amps.

 

[davedotco]

Yes this is true. I always seem to thoroughly research products before buying and sometimes it's a curse. It might be better to be ignorant and just enjoy what end up with. There's always better. Anyway, I had a chat with my local hi fi store and they are happy to use the 651W that I ordered as a demo so I can listen to both with my stream magic. It won't be with my speakers, in my home but at least I'll get an idea of the sonic differences between the 2, hopefully.

I doubt there will be any sound quality issues, it is primarily about the functionality, just make sure the volume control works nicely and that it sounds good at the lowest volume settings, it is at these levels that any issue will show up.

I went for the shoot out today between the 2 amps. The integrated amp using SM6 as source sounded warmer, and, to me more pleasing. The Power amp, using SM6 as digital preamp, sounded less warm but had much more detail and was more dynamic, also better timing. Personally I preferred the warmer sound of the integrated, but the salesman said the power amp will warm up as its run in and only sounded that way because it was fresh out of the box, unlike the integrated that was their demo and has had hours and hours of play time.

Amplifiers need to be at optimum temperature, from new this may take a day or two. After that most of the changes will be you as you adapt to the sound.

The pre-amp (section in the integrated) will be causing the extra warmth, my personal experience is that 'warmer' is not so good long term, but that is hugely personal, i think almost all amplifier/systems are too warm, but thats me.

Try and give it another go after a day or two, then decide.

Thanks for the advice On the box of the power amp it says to run the amp for a constant 36 hours before use. Does this mean just have it on? Or do I need to be playing music for 36 hours? Sorry if that's a silly question! Obviously I don't want to be playing music for 36 hours straight, so could I just not plug the speakers in and have it playing music? Or will the fact there's an open circuit do damage? I know this was a no no for tube amps.

When designing an amplifier the comonents are spec'd and chosen for their performance at normal operating temperature, which is probably slightly warm. There are also theories regarding running in of power capacitors but usually a 24-48 hours is enough.

Power transistors come up to temperature in a matter of minutes but lower level circuitry may take a day or two. You need the amp to be actually playing into a load, ie speakers, but modest levels are fine, it will settle down in a few days.

 

[Obagleyfreer]

Yes this is true. I always seem to thoroughly research products before buying and sometimes it's a curse. It might be better to be ignorant and just enjoy what end up with. There's always better. Anyway, I had a chat with my local hi fi store and they are happy to use the 651W that I ordered as a demo so I can listen to both with my stream magic. It won't be with my speakers, in my home but at least I'll get an idea of the sonic differences between the 2, hopefully.

I doubt there will be any sound quality issues, it is primarily about the functionality, just make sure the volume control works nicely and that it sounds good at the lowest volume settings, it is at these levels that any issue will show up.

I went for the shoot out today between the 2 amps. The integrated amp using SM6 as source sounded warmer, and, to me more pleasing. The Power amp, using SM6 as digital preamp, sounded less warm but had much more detail and was more dynamic, also better timing. Personally I preferred the warmer sound of the integrated, but the salesman said the power amp will warm up as its run in and only sounded that way because it was fresh out of the box, unlike the integrated that was their demo and has had hours and hours of play time.

Amplifiers need to be at optimum temperature, from new this may take a day or two. After that most of the changes will be you as you adapt to the sound.

The pre-amp (section in the integrated) will be causing the extra warmth, my personal experience is that 'warmer' is not so good long term, but that is hugely personal, i think almost all amplifier/systems are too warm, but thats me.

Try and give it another go after a day or two, then decide.

Thanks for the advice On the box of the power amp it says to run the amp for a constant 36 hours before use. Does this mean just have it on? Or do I need to be playing music for 36 hours? Sorry if that's a silly question! Obviously I don't want to be playing music for 36 hours straight, so could I just not plug the speakers in and have it playing music? Or will the fact there's an open circuit do damage? I know this was a no no for tube amps.

When designing an amplifier the comonents are spec'd and chosen for their performance at normal operating temperature, which is probably slightly warm. There are also theories regarding running in of power capacitors but usually a 24-48 hours is enough.

Power transistors come up to temperature in a matter of minutes but lower level circuitry may take a day or two. You need the amp to be actually playing into a load, ie speakers, but modest levels are fine, it will settle down in a few days.

 

Thank you!

 

[steve_1979]

Yes this is true. I always seem to thoroughly research products before buying and sometimes it's a curse. It might be better to be ignorant and just enjoy what end up with. There's always better. Anyway, I had a chat with my local hi fi store and they are happy to use the 651W that I ordered as a demo so I can listen to both with my stream magic. It won't be with my speakers, in my home but at least I'll get an idea of the sonic differences between the 2, hopefully.

I doubt there will be any sound quality issues, it is primarily about the functionality, just make sure the volume control works nicely and that it sounds good at the lowest volume settings, it is at these levels that any issue will show up.

I went for the shoot out today between the 2 amps. The integrated amp using SM6 as source sounded warmer, and, to me more pleasing. The Power amp, using SM6 as digital preamp, sounded less warm but had much more detail and was more dynamic, also better timing. Personally I preferred the warmer sound of the integrated, but the salesman said the power amp will warm up as its run in and only sounded that way because it was fresh out of the box, unlike the integrated that was their demo and has had hours and hours of play time.

Amplifiers need to be at optimum temperature, from new this may take a day or two. After that most of the changes will be you as you adapt to the sound.

The pre-amp (section in the integrated) will be causing the extra warmth, my personal experience is that 'warmer' is not so good long term, but that is hugely personal, i think almost all amplifier/systems are too warm, but thats me.

Try and give it another go after a day or two, then decide.

Thanks for the advice On the box of the power amp it says to run the amp for a constant 36 hours before use. Does this mean just have it on? Or do I need to be playing music for 36 hours? Sorry if that's a silly question! Obviously I don't want to be playing music for 36 hours straight, so could I just not plug the speakers in and have it playing music? Or will the fact there's an open circuit do damage? I know this was a no no for tube amps.

When designing an amplifier the comonents are spec'd and chosen for their performance at normal operating temperature, which is probably slightly warm. There are also theories regarding running in of power capacitors but usually a 24-48 hours is enough.

Power transistors come up to temperature in a matter of minutes but lower level circuitry may take a day or two. You need the amp to be actually playing into a load, ie speakers, but modest levels are fine, it will settle down in a few days.

Two days before it sounds at it's best? Who could be bothered with all that faffing about.

If I can't just turn on a hifi and listen to some music straight away then turn it off again when I'm finnished then it's a flawed design IMO. A well designed piece of equipment will sound exactly the same after a two second warm up as it does after two days IME.

 

[Overdose]

Yes this is true. I always seem to thoroughly research products before buying and sometimes it's a curse. It might be better to be ignorant and just enjoy what end up with. There's always better. Anyway, I had a chat with my local hi fi store and they are happy to use the 651W that I ordered as a demo so I can listen to both with my stream magic. It won't be with my speakers, in my home but at least I'll get an idea of the sonic differences between the 2, hopefully.

I doubt there will be any sound quality issues, it is primarily about the functionality, just make sure the volume control works nicely and that it sounds good at the lowest volume settings, it is at these levels that any issue will show up.

I went for the shoot out today between the 2 amps. The integrated amp using SM6 as source sounded warmer, and, to me more pleasing. The Power amp, using SM6 as digital preamp, sounded less warm but had much more detail and was more dynamic, also better timing. Personally I preferred the warmer sound of the integrated, but the salesman said the power amp will warm up as its run in and only sounded that way because it was fresh out of the box, unlike the integrated that was their demo and has had hours and hours of play time.

Amplifiers need to be at optimum temperature, from new this may take a day or two. After that most of the changes will be you as you adapt to the sound.

The pre-amp (section in the integrated) will be causing the extra warmth, my personal experience is that 'warmer' is not so good long term, but that is hugely personal, i think almost all amplifier/systems are too warm, but thats me.

Try and give it another go after a day or two, then decide.

Any competently designed electronics will work 'out of the box'. The components used in hifi equipment have tolerances that far exceed the conditions found in a normal domestic environment. If the components varied in their ability to work under modest temperature ranges, they would not be fit for purpose.

As an example, a power capacitor.

 

[davedotco]

Steve and Overdose.

My experience tells me otherwise, not trying to be contradictory, just explaining my views.

I am not an electronics engineer and I am extremely wary of the long 'run in' times advocated in some quarters, nonsense in the main i think.

However I am a believer in temperature sensitivity. It was/is always my understanding that the measured characteristics of some active components will vary with temperature and the swing from 'stone cold' to operating temperature can be quite large. I have always believed this has an effect, though I accept that my judgement on this is entirely subjective.

I see no reasons why some equipment might not exhibit this effect wheras some might, I do not consider it poor design if the equipment works well and is 'to spec' at normal operating temperatures.