My Audio PC build

[southpaw]

Well I'm not quite building just yet, still specing the parts...

A couple of bits that would help me pick the components are:

Should I buy a case that has room for a soundcard or just go for usb output?

Is there any negative SQ effect from having dc input on the m'board versus a separate psu board?

Is an external DVD/Blueray a definate no no or is it a perfectly sensible alertnative?

I'm sure there was another but its gone for now...

edit - just remembered it

[Deleted]

southpaw
I would try to make room for an internal soundcard.
A decent soundcard also has additional PSU filtering.
Many people go for USB audio , but USB implementation in the mother board can often be poor. Presently, I have a project in RG that attempts to correct some of the USB failings re PSU noise and the resultant degradation of audio.
Properly implemented SPDIF (coax) is far better than most people give it credit for, and can shit all over USB DACs such as the Benchmark.Some people with laptops even need to resort to battery power for playing audio via USB.

Is an external DVD/Blueray a definate no no or is it a perfectly sensible alertnative?

Some people get great results using external BR writers,
especially if anti vibration measures are taken.
Alex

[XTRProf]

Heh, heh, this I think will be good enough for an "audio pc". Of course, you must have a good dac (2 channnel or surround) for it to sound any good.









I would have bought one if it has 3D support. Almost perfect as it's standalone and independent of the PC. I'm not sure whether it can play hirez flac or other music files although it says HD audio. Also how good the media player sound as compared to those paid media players which are definitely a step up in the sound quality according to reviews?


Specs: www.acryan.com/product/playonhd2/specifications/

[southpaw]

Had a look at a Sonos system yesterday and it ticks most of the boxes for me at present. Wife is completely sold on it which helps.

Still not sure I've even got the slightest handle on this computer audio stuff so will let me listen whilst I read up

[southpaw]

Decided with a baby due this week that a simple Sonos system was the way forward.

[southpaw]

Sonos unboxed this evening and listening to music in under 30 mins

Good but not earth shattering music at the end of my fingertips via android phone = bliss Can't wait to plug the dac in and start playing with psus

[mrarroyo]

I almost bought a Sonos but found a cheap used Squeezebox V3 and a Duet. Both for $200 USD.

[XTRProf]

Aug 12, 2011 2:02:27 GMT mrarroyo said:

I almost bought a Sonos but found a cheap used Squeezebox V3 and a Duet. Both for $200 USD.

Hi Miguel,

Have you compared a Pure Music or it's competitors on a Mac Mini versus the Squeezebox Duet in terms of sound quality? Really, I'm interested in how the Mac Mini sound with a Leopard or Lion.

Thanks.

[mrarroyo]

Chong, I do not own a Mac Mini my comparison was done using an iMac 21.5 using Leopard. Sorry.

[XTRProf]

Aug 12, 2011 10:15:24 GMT mrarroyo said:

Chong, I do not own a Mac Mini my comparison was done using an iMac 21.5 using Leopard. Sorry.

Then an iMac with Leopard will also do. Just to have a rough idea which will be better. Thanks.

[mrarroyo]

I will look for my notes. From a convenience point of view iMac, the Pure Music was ok but not a major improvement. I had to listen hard and could hardly hear a difference, at least it is not too expensive.

[Garage1217]

For me and my audio PC build, the following related to audio were important to me...
- Very good power supply. Seasonic, Enermax and some corsair units are my top choices.
- External USB sound card "mobo should support at least USB 2.0" I like the E-MU USB based devices such as the 0204 and 0404
- Very quiet fans with stellar thermal performance via the case airflow

[Deleted]

Aug 14, 2011 6:17:14 GMT Garage1217 said:

For me and my audio PC build, the following related to audio were important to me...
- Very good power supply. Seasonic, Enermax and some corsair units are my top choices.
- External USB sound card "mobo should support at least USB 2.0" I like the E-MU USB based devices such as the 0204 and 0404
- Very quiet fans with stellar thermal performance via the case airflow

garage1217
It is best to choose a PSU with a reputation for a low PSU ripple content.I think Seasonic may have a couple of those in it's product range ?
If you must use fans, it is best to have them rubber mounted, and NOT PWM speed controlled from the motherboard.Direct DC control via a thermistor or rheostat would be better.
PWM control of fans will make a quiet aftermarket fan noisier, with more vibration.
If you are going to use an external USB soundcard, try to choose one that can also have power supplied from an external Linear PSU.
Alex

[XTRProf]

Talking of fans, which brand computer fan is the queitest that you guys had experienced? So far, I saw one 18dba or 20dba locally. Sorry, around those figures as I can't remember correctly.

[xerxes]

Talking of fans, which brand computer fan is the queitest that you guys had experienced? So far, I saw one 18dba or 20dba locally. Sorry, around those figures as I can't remember correctly.

This might give you a few ideas:
www.bit-tech.net/hardware/cooling/2009/09/28/what-s-the-best-case-fan/1

I have a couple of these in my PC: www.akasa.com.tw/update.php?tpl=product/product.detail.tpl&no=181&type=Fans&type_sub=Ultra%20Quiet%20Fan&model=AK-183-L2B they are pretty much inaudible.

[XTRProf]

Aug 15, 2011 3:01:14 GMT xerxes said:

This might give you a few ideas:
www.bit-tech.net/hardware/cooling/2009/09/28/what-s-the-best-case-fan/1

I have a couple of these in my PC: www.akasa.com.tw/update.php?tpl=product/product.detail.tpl&no=181&type=Fans&type_sub=Ultra%20Quiet%20Fan&model=AK-183-L2B they are pretty much inaudible.

Real interesting. Thanks very much.


Some IMPORTANT highlights from the 120mm computer fan test link:


1) Level meter positioned 50cm away from the intake side of the fan being tested. We chose a distance of 50cm, as this is the typical distance that most people will sit from their PCs at home. Also, if we took the measurement from any closer than 50cm, the results would be distorted. This is incredibly important, as the further away the sound level meter is from the sound source then the lower the reading will be. The fans were powered by a passively cooled PSU, so as not to increase the sound level in the room, and held in place by two metal clamps with a reflecting surface behind.


MY POINT: With a typical forced draft computer PSU, the overall noise will be higher than what the low noise fans can gave. So it will very very wise to have a passive cooling linear PSU and the least fans (yup, even low noise ones as the noise adds up), as practically possible, for your HIREZ hifi computer audio.

2) The sound pressure level of each fan was recorded between 80Hz and 20KHz.


MY POINT: Yup, that's important for a hifi computer audio.

3) The background noise level of the room averaged 19.3dBA during the test period, although it dropped below this level several times. For this reason, any fan that measured less than 19.3dBA has been graphed with a sound level of 19.3dBA.


MY POINT: This is the lowest noise threshold of the test room carried out in Intertek’s home-cinema listening room, which is designed to meet the IEC 286-13 standard. So any fan at 19.3dBA is already the limit than we can face. Our home will be much higher noise level unless you also have an IEC 286-13 HT room. Really, I can't think of many except for Ian in his studio. So any fan spec at 19.3dbA and below is already OVERQUALIFY to do a very good job in a HIREZ hifi computer audio.

4) After testing all the fans, it can be said that any fan producing 25dBA or less was barely audible, while fans emitting between 26dBA and 30dBA were audible but not annoying. Fans measured above 31dBA were perceived to be too loud for comfort.


MY POINT: Yup, reflecting what I had just written.

5) Not shown on the graphs, but also important, were the subjective observations we made about any particularly unpleasant noises produced by the fans. This is crucial, since the motors of some fans can produce sound at irritating frequencies, which can be very distracting, even if they’re not particularly loud.


MY POINT: Precisely what the hifi subjective brigade is all along talking about. So one point down for the hifi objective brigade.

[Deleted]

Perhaps one of the 2 at the bottom of this Jaycar page would be suitable types ?
www.jaycar.com.au/productResults.asp?keywords=120mm+fan&keyform=KEYWORD&SUBMIT.x=13&SUBMIT.y=18

[XTRProf]

Aug 15, 2011 5:18:56 GMT @sandyk said:

Perhaps one of the 2 at the bottom of this Jaycar page would be suitable types ?
www.jaycar.com.au/productResults.asp?keywords=120mm+fan&keyform=KEYWORD&SUBMIT.x=13&SUBMIT.y=18

Yup, the 2nd last one at Noise (dBA) 20.2. The last one is at 25 dBA.

The akasa shown in the a/m link is even better at 18dBA.

[xerxes]

Yup, the 2nd last one at Noise (dBA) 20.2. The last one is at 25 dBA.

The akasa shown in the a/m link is even better at 18dBA.

Unfortunately, there isn't a standard method of measuring fan noise, so some manufacturers noise specifications might have to be taken with a fair pinch of salt.

Also I wouldn't worry about a passively cooled PSU, I have one of these: www.ocztechnology.com/ocz-powerstream-power-supply-eol.html. It has two 80mm fans in it and I can't hear it from where I sit 6 or 7 feet away, they spin very slowly unless near full load and wouldn't get anywhere near that in a "Media" PC. In fact the noisiest thing in the PC at the moment is the hard drive and I will change that soon for something quieter.

[Will]

Is there any negative SQ effect from having dc input on the m'board versus a separate psu board?

Hi Southpaw,

If anything, this can actually be a better thing, if you can get a linear supply to feed into the dc input. The on-motherboard switching/dc-dc converters will produce noise, but there is less noise being fed in, with the typical noise from a smps no longer being a factor.

Of course, if you are using a really good quality smps, then that'll be fine.

[Will]

On the fan side of things, what Alex mentions regarding avoiding PWM controllers is spot on. The output of these can cause the windings in the fan to 'whine' or 'sing' in relation to the frequency of the output. Much better to use a simple voltage based controller.

I've a lot of experience with quiet computer fans, back from when I used to build quiet gaming pc's for pocket money, and the typical pc had many fans and sounded like a turbine!

When it comes to fans the amount of air measured in CFM is as important as the noise it makes. You can have a very quiet fan, but it will not shift enough air to keep things cool, so take this into consideration when assessing fans. SilenX make pretty good fans www.silenx.com/ixtremaprofans.asp?sku=ixp-74-09 but their measurements are a but suspect, and are a bit pricey

Nexus make very good fans, and are very quiet www.nexustek.nl/NXS-nexus120mmrealsilentcasefan.htm and if you can cope without the pretty colours, are much cheaper if you buy the OEM version Yate Loon D12 SL12

Silentpcreview win the Ubergeek award for fan noise testing procedure www.silentpcreview.com/article1040-page1.html and their forums have loads of good info on quieting your pc.

Other points on the fan front, don't screw the fan to the case, use silicone fan mounts, as they decouple the fan vibrations from the pc case. www.quietpc.com/gb-en-gbp/products/casefanaccessories/afm02b-group

Also, check the fans for knackered bearings, even on new ones. I've had new ones sound quite agricultural, and found notchy bearings to be the cause.

[XTRProf]

Aug 15, 2011 12:03:49 GMT xerxes said:

Also I wouldn't worry about a passively cooled PSU, I have one of these: www.ocztechnology.com/ocz-powerstream-power-supply-eol.html. It has two 80mm fans in it and I can't hear it from where I sit 6 or 7 feet away, they spin very slowly unless near full load and wouldn't get anywhere near that in a "Media" PC. In fact the noisiest thing in the PC at the moment is the hard drive and I will change that soon for something quieter.

Actually, the passive cooled linear PS also has another advantage. It's not in switch mode.

Also, forget about HD, use SSD. Completely no noise. Of course, we have to accept the $$$ factor.

[xerxes]

Also, forget about HD, use SSD. Completely no noise. Of course, we have to accept the $$$ factor.

I'm not convinced by the need for SSD, it just happens that the old 80Gb drive I'm using as the boot/OS drive is exceptionally noisey. The 2TB drive on which I have the actual music stored is virtually silent. When I upgrade my main PC soon, I'll rebuild my Media PC with a different HD for the OS and in a different case I have with rubber hard drive mounts.

[XTRProf]

Aug 16, 2011 15:23:20 GMT xerxes said:

I'm not convinced by the need for SSD, it just happens that the old 80Gb drive I'm using as the boot/OS drive is exceptionally noisey.

Yeah, don't forget the supposedly lower jitter with SSD as well as no moving parts. Actually, I still don't understand why the technical people is still talking of jitter affecting sound when it is already into ns and ps for jitter. 10^-9 or -12 seconds we are talking about.
Much faster than any highend camera shutter speed.

[Deleted]

Aug 17, 2011 4:50:04 GMT XTRProf said:

Aug 16, 2011 15:23:20 GMT xerxes said:

I'm not convinced by the need for SSD, it just happens that the old 80Gb drive I'm using as the boot/OS drive is exceptionally noisey.

Yeah, don't forget the supposedly lower jitter with SSD as well as no moving parts. Actually, I still don't understand why the technical people is still talking of jitter affecting sound when it is already into ns and ps for jitter. 10^-9 or -12 seconds we are talking about.
Much faster than any highend camera shutter speed.

I have seen a report where it was claimed that random Jitter can
cause low level wideband noise.