Paul,

Thanks for mentioning this, I was puzzled about how to tie the signal grounds using two transformers to power the modules for one channel (eg say left side speaker). Using PE it is possibly easy to establish a "good" sinal ground but poor for sound quality. In our setups with signal ground established by the PE back in the pc it could be more difficult to iron out any differences that two transformers in the same channel try to exert on the singnal ground.

I may just go for 2 x 500 va transformers to cater for the additional modules.

Cheers,

Nick.

Hey Paul,

Thanks for posting the internal shots, we have ended up with very similar layout of the modules but in the next version I build am going to put the transformers in a separate case like yours. Good point about hard wiring the psu connections I think I will do that too.

Now i have to work out how to get a good layout with 8 modules and 4 transformers 

Cheers,

Nick.

Jud hi,

Is that a linn lp12 record deck peaking out from behind the tv ?

Nick.

Mani Peter hi,

I think you have picked up what I was suggesting correctly but just to confirm.

For a long time my "standard" PC set up disabled unused devices in BIOS. These include mobo sound card, USB, serial port, additional SATA controller types and LAN cards.

I was messing about with device settings in Device Manager and noticed a very slight I improvement in sound turning some disabled devices back on. This got me thinking if this happens at the OS level what about at the hardware level ?

So what I am suggesting in the update to the tweaks is:

A) In BIOS turn ON mobo sound card, USB, serial port, additional SATA controller types and LAN cards.

B) When these devices are turned on in BIOS  go into Device Manager and disable each of them.

Take a listen. In my case with the asus x79 mobo a whole layer of hardness and sibilance just went away  You may find that LAN card back on in BIOS is a bit "accurate" sounding but after trying listening to LAN  off / on a few times, for now I am sticking with LAN on.

Cheers Nick.

Update I meant to say I was sticking with LAN ON in bios in the last line (now edited to say "on").

Stanley hi,

First back up your music drive (you proberbly don't want to re-rip 100s of CDs).

Then from there I would try to add a second partition to the music drive. I would make it at least 20gb so windows does not run out of space. Often you can add a partition and not lose the data on the drive but it's not guaranteed which is why you must back up your music.

Install windows on to the new partition and then install XX on the music drive either in the new windows partition or the partition where the music lives.

This should give you all of your OS music and XX on the same single physical HDD.

Hope this helps,

Nick.

Hi,

I wanted to offer some updates to this list of tweeks. The reason for this it that the noise problem I had is my system when the list was drawn up is now fixed. This means that I can hear much much being resolved now making some updated to the tweaks nessasary.

I have added additional comments below to items where observations have changed, one of which is very important to sound quality at least on my Asus X79WS MoBo.

Hope this is helpful, I would particularly recommend that Mani and Brian give 11c a go as we all have the same model of Mobo.

Regards,

Nick.

ps the comments are based on the High Res timer being disabled at a BIOS level as per another recent post.


Summary of tweeks.

1)   Eliminate ALL fans (CPU fan case fans etc)
2)   Take power off ALL drives but one (OS XX and Music on the single HDD)
3)   Power the one HDD from a linear power supply
4)   Remove power connections from DVD and Floppy Drives etc
5)   Turn off hyper threading

I plan to check this comment again and will post back.

6)   Over Clock the CPU
7)   Disable CPU “Clock Spreading” 
8 )   Turn off Intel Virtualisation
9)   Use PCIe USB 3 (NEC chipset)
10)   XX processor scheme 3, SFS around 350mb,

This was based on earlier versions of XX, on v09-z75 I am using SFS of 2mb (as is the case with many).
 
11)   Hygiene factor tweaks (Old hat stuff but for good measure)
a.   Disable Data Execution support (in Bios)
b.   Disable all Devices not needed for music (extra SATA controllers, USB ports etc etc in Device Manager)
c.   Disable all devices not used for Music in  Bios (Mobo
USB, Sound card, COM ports etc)

This was the big surprise for me, with my system now much more able to resolve than before I find that disabling devices in Bios is very bad for sound quality. With unused devices disabled I get a very unplesant hardness in the upper mid range, life leaves the music and it just sounds more digital. Its worth trying turning these devices on if you currently have them turned off in Bios, I was really surprised when tried this.

I have not gone as far as turning the LAN cards back on in Bios but that is the next test, will update again if this is posertive.

Note that whilst devices are back on in Bios I still have all of these devices disabled in Device Manager as per 11b)

I was just cruising google for information on master clocks and came across a billing on 6Moons saying that their test of the NOS1 and XXHE is coming soon.

I'm very interested to see what they find, I'm sure it will be good :-)

Nick.

http://www.6moons.com/audioreviews/audioreviews.html

Tore hi,

Sounds like it could be the USB 3 driver version that you have for the card. When I first tried the 2 port card the driver that came with the card would not drive the NOS1. For the two port Renesas chipset this driver version works and sounds good.

Renesas USB 3.0 Driver 2.0.34.0

Might be worth finding a copy and trying this assuming it will drive the 4 port card as well. If it won't drive the 4 port card try alternate version for the four port chipset. With luck this will get you going .

Cheers,

Nick.

Mani hi,

Congratulations what a great speaker, I would never have thought to look on eBay for such a rare and hi-end design.

Is the noise always there (eg with system just turned on without music playing) or is the noise something you get in the background while music is being played ?

My long term noise problem turned out to be my speaker cables acting as aerials and upsetting my NOS/gainclones. I would not rule out cables on the output side of your system, perhaps try moving them around to see if the noise level varies.

Out of interest what level of attenuation do you need to play at on the XXHE volume control to play loud ?

Cheers,

Nick.

Coen,

Thanks again, I'll start with the feedback loop. I’ve been messing about with zero feedback valve amps for a few years before the gainlones came along so the idea of adding more feedback didn’t sit too well. It’s good to know that more feedback in a gainclone could be good for sound quality  .

Also its interesting what you are saying about putting the passive potential divider before the caps.

Time to get some parts to give it a go.

Regards,

Nick.

Leo, Paul, Coen, Peter,

Thanks all for your help with my gain question.

It's interesting that pointers are towards increasing feedback to reduce active gain and using passive attenuation, looking at it I think I may need to use both to drop 15db.

The gain factor of my gainclones 33.3 or 30.4db (thanks Paul). As Coen pointed out the LM3775 according the data sheet should not really go below 26db, so changing the feedback resistors could yield a 4db reduction. I'm worried that I may end up listening to a lot of negative feedback, but its easy to try so this could be option 1.

Option 2 is to apply passive attenuation on the inputs. The choice here would be to apply the attenuation before the input caps or after the caps and before the Gainclone modules. I guess after the caps would be best so the signal level is higher as it traverses the caps. The problem here is that I have just bought these rather nice (and expensive) mundorf silver gold oil caps which are the correct size for the standard gain clone module 22k input load. I like Coens suggestion about keeping the "input load" of a resistor potential divider as low as the NOS output can handle to keep series resistance of the input as low as possible. To lose 9 db on the input I could go with a potential divider of 820 and 270 ohms. The problem is at these values I would need input caps of 100uf a bit bigger than the new 5.6uf  mundorfs. Hummmm a bit to think about here.

Thanks guys for the help so far.

Nick.

Hi,

My system has too much gain and I wanted to ask for comments and advice about losing gain with the least impact on sound quality.

To connect my NOS to my gainclone amps, as I am using phase alignment, I have 5.6 uf capacitors on the inputs to my gainclone modules. The input capacitors work with the 22k ohm input load resistor of the gainclones to give a high pass filter with a -3db power point of 1.3 hz (optimal point for response down to 13hz). All good so far.

The problem I have it that in my system as a whole the 2v output level of the NOS combined with the 28db gain of the gainclones and 105db/m/w response of my speaker means that I have about 15db too much gain in the replay chain.

This means to set a reasonable playback level using only the XXHE software  volume control to generate a "loud" listening level I have to play at a -30db volume setting in XXHE. I think that the 32 bit based volume calculations and 24 bid DAC have the headroom to play at this level but the issue is that -30 db turns the 2 volt full scale NOS output into only 6mv full scale output from the NOS ! I can hear that at this signal amplitude by the time the signal has traversed interconnects and gainclone input caps, sound quality is being impacted. I have been using transformer volume controls (TVC's) to "soak up" some surplus gain but I am very keen to take these out of the system.

My question is dose anyone have any ideas about how I can lose about 15 db of signal level. Ideally I would do this after the signal has been passed through the 5.6uf input caps if the gainclones. The obvious way is to pass the signal through a potential divider with resisters chosen to lose the gain. I have been trying this but so far have not had great results as far as sound quality is concerned (this might just be the resistor values I have tried so far). Does anyone have any ideas on a good way to lose 15 db of gain whilst maintaining sound quality ?

Thanks for any suggestions.

Nick.

Juan hi,

Those Soundlabs are LARGE 

Quote from the Soundlab link you posted

" A-1's are notoriously-difficult to drive, requiring massive voltage-swing and rock-solid stability into nearly a dead short above 20kHz; few amplifiers at any price are up to the task."

Now that is what I call a load for any amp 

My Duos are quite an easy load particularly for a solid state amp like gain clones to drive. The subs are active as well which helps even more. I guess the matching transformers might help with lower power valve amps particularly if there are not suitable output transformer tap impedances on the amp for the speaker load the valve amp is driving.

Best regards,

Nick.

Juan hi,

I had looked at them on the webs site before and wondered if they may sound good. Was there any particular reason that you took them out of your system ?

Best,

Nick.

My 10 cents....

First anti cables.

I followed the same cable construction as Paul for bi wiring my speakers with enamelled copper wires.

The results are remarkable, the sound is very smooth but with all available detail passing through. Without a doubt the best speaker cable I have ever had in my system by a considerable distance. The cables took a day to build ( I used an electric drill to twist them  ) and cost about £25 for 4 runs of 6 m length lol !

Second comment is about the effect of REMOVING my old cables.

Oh boy, I have been trying to track down the weirdest noise problem in my system for 18 months (it was so bad that playing XXHE at -144db volume I could hear distorted music playing even with my DAC section not powered up).  In the name of diagnostics much of my system has been swooped for upgraded components but still no fix that was UNTIL I removed the old speaker cables and put anti cables into the system. Now the system has no noise problem what so ever . In then end it seems that the cause was my old hybrid copper / carbon construction speaker cables that were in some way interacting with my system / general environment and the result was the noise problem.

For both of the above reasons, I and a BIG fan of anti cables.

Nick.