Hey Boleary - I find exactly the same. I was listening to a very high quality simple female voice recording last night and ended up on SFS=2 because anything higher seemed to smear the voice.
Paul

I couldn't help myself Amazon stock reduced further.
P

So before with the optical drive connected I was 

Now with the optical drive disconnected I am    

Surprising improvement.

what is surprising is how much difference a change of just 1 in SFS makes at the lower values.

I agree SFS 5 to 10 is about right in my system now. Listening to a number of different albums this afternoon (even some difficult & poor recordings) and no problem it sounds fine. I have not heard this level of detail before that is so easy to listen to.

So disconnecting the CD drive makes this difference? wow.

I have USB 2 and 3 on the motherboard disabled in BIOS with just USB 3 (for NOS1) on a PCi extender card enabled (thanks for that one Nick!) and that made a big difference.

P

Hey Boleary - thanks very useful I had forgotten to unplug my CD drive which I have now just done. So now I can run at lower SFS settings generally SFS=10 is now best but lower for good recordings. So thanks that is another step forward.

Paul

Mani - I do not agree that it is specific to Gainclones - but I do think it may be specific to grounding arrangements. After all I had noise problems with my Gainclones before I changed the grounding arrangements.

If I bring my amp to yours and connect it to your NOS which in turn is connected to your PC we know that the grounding arrangements will be OK (after all it will be identical to mine). If we then connect the "Swings" and there is a noise problem we know where the problem is coming from. If instead we connect my bookshelf speakers (which I can bring) I am pretty sure there will be no noise. But of course who knows weird things happen. Just check out what happened to Nick that has to be the weirdest thing I have come across.

Anyway whatever any excuse for a "boys and their toys" day.

P

I would be interested in the experience of others. I am currently running with SFS=20. However, until recently I was running with SFS=430 and the reason was that the sound was edgy and I used SFS=430 to "smooth" the sound.

Now that the sound quality is sorted out (see http://www.phasure.com/index.php?topic=2299.0) I find that SFS=20 sounds better but probably not by that much.

So the question - do others find that when everything is working correctly smaller SFS (and related Q1 settings) are better. So a smaller buffer is better provided that everything is working correctly?

Paul

Mani - If I have nothing connected to the input of my amps I get noise and a fair amount of it. That is because the ground in my amp is not connected to anything so I have to connect it to NOS1 via i/c's. Oh and NOS1 ground is not connected to anything either so it has to be connected to the PC via the USB cable (which allegedly is connected to earth). So to get very low noise in my system the amp  NOS and PC all have to be connected together. By the way the fact the USB is connected to earth does not affect noise in my system. I know that because I used Nick's fibre USB link (thereby galvanically isolating NOS1 from the PC) and it made no difference to noise at all (that I could hear). So earth or no earth the noise levels in my system are very very low (if I remember rightly you stuck your "shell like" into my bass cone to 'av a listen).

Not sure if that helps but that is what happened for me.

By the way my i/c's to NOS are home made thin gauge silver wire basically simple twist with no shielding. And as I think you know my speaker cables are twisted lacquer coated copper wire. But with all the experiments with those I have not had a noise problem. But that is here in my system and we are all different.

Paul

Mani - when I had noise problems they were just audible from the listening position which is why I had not put any serious effort into resolving them (just too busy listening to music!!). Peter convinced me that noise is very bad thing so started my search to reduce it. When I did reduce it to very low levels I was shocked at the improvement in SQ. That was a big lesson for me - noise is indeed very very bad (from my experience anyway). And to think that every system I have previously had over the years has had discernible noise despite my best efforts to reduce it. Anyway best of luck.

By the way I guess that you are now officially a "swinger" ha ha.

Paul

Mani - if it is any help I could bring my amp along - I know that the grounding arrangement with my amp together with NOS1 and a PC provides a dead quiet background in my system and also Nicks. We would try it at yours together with the Swings and perhaps another pair of speakers. It might help identify where the problem is. I know you have other amps etc around that you have probably already used but it might help provide some pointers.
P

Hi Mani,

Nice buy and welcome .

I would say I am certainly in that club!!!!. My problems were down to grounding arrangements in my amp. which are discussed in "Gainclone Heaven" thread. Not sure I can add anything and I would not have thought your amps would have grounding issues. Anyway best of luck and I would love to have a listen to your swinging new speakers sometime when sorted or even before sorted to see if we can collectively come up with something.

All the best

Paul

Nick - this is a quote from Peter Daniel on the Audiosector forum about gain maybe As discussed above R1 will affect SQ but its easy enough to try it. Also I suppose that R1 at 22k may affect the L/C equation for the input caps but again easy enough to work out.

Quote
It's best to change the gain with R3, but I wouldn't go over 1k6 or so. If you need additional gain trimming, increase R1 (22k will give you -6dB gain reduction)
Unquote

Maybe 22k input R will not be ideal given the low output impedance of NOS1 - any comments Peter?

Am looking forward to hearing your system. After all the mods I have made to my system recently I have some spare amp boards (populated and burned in) I measured the quiescent offset voltages so if you measure the offset voltages on your amps we may (but we will need some luck) be able to find a combination where the Left Right offsets are reasonably well matched (at least for your bass units) which I assume (?) do not have capacitors in series with them in the crossover. I have matched my amps to within 5 mv offset for the bass units and it was worth doing (previously I had about 60mv offset difference) removing "confusion" in the stereo image and just sounded more coherent overall.

Paul

Isn't downsampling more of a problem than upsampling?. Upsampling moves aliasing images outside the audio band the more upsampling the further outside the audio band (a key reason to upsample). Whereas downsampling moves the aliasing images inside the audio band (yuk) so downsampling has to involve a brick wall filter which is the only way the effect of those aliasing images can be mitigated.

So why not take an analogue recording and create one digital master at say 24/192 and another at 16/44 and then compare them? Peter - can you do that with the PMII? I guess maybe it does not which would be a great shame.

P

Hey Nick - you can set your gain to whatever you need without affecting quality. The circuit diagram of your amps is below (I think!) and the gain you currently have will be:

Gain is  =1+Rf/R3, so 1+(22.1K/680)=33.5dB

You can change Rf and R3 to give a lower gain without affecting quality.

I would have thought best to change Rf and leave R3 at 680ohm. If Rf is the same spec i.e. Caddock as in the original kit then quality should not be affected.

Cheers

Paul