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baardbaard
2010-02-09, 15:02
The SB3 is packaged with a very wimpy and noisy switching power supply that inhibits its true potential.

- I have an aftermarket PS for my SB3 - can I use it on Touch?
- What is the DC requirement for the Touch?


Baard

JJZolx
2010-02-09, 15:12
The SB3 is packaged with a very wimpy and noisy switching power supply that inhibits its true potential.

- I have an aftermarket PS for my SB3 - can I use it on Touch?
- What is the DC requirement for the Touch?

The only difference is that the power supply that comes with the Touch is rated 3 Amp. It needs the extra to power the USB port. Same voltage and connector.

baardbaard
2010-02-09, 15:16
Nice, I can re-use this PS from:
http://www.welbornelabs.com/squeeze.htm

ratet 5V and 4A

Baard

Phil Leigh
2010-02-09, 15:32
The SB3 is packaged with a very wimpy and noisy switching power supply that inhibits its true potential.

- I have an aftermarket PS for my SB3 - can I use it on Touch?
- What is the DC requirement for the Touch?


Baard
In your opinion. This is not backed up by fact.
It is absolutely not "wimpy" - it delivers the current required. As for "noisy"... well, most of the "noise" comes from the internal DC switcher and the VFD.

baardbaard
2010-02-10, 00:50
Wimpey, flimsy, under powered etc…..are you sure you want a debate on this topic meaning there is no point in upgrading the SB3 power supply from an audiophile point of view?

Or was it just my way of describing the standard PS unit that was difficult for you to overcome?

Phil Leigh
2010-02-10, 01:13
Wimpey, flimsy, under powered etc…..are you sure you want a debate on this topic meaning there is no point in upgrading the SB3 power supply from an audiophile point of view?

Or was it just my way of describing the standard PS unit that was difficult for you to overcome?

It is not underpowered/wimpy as it delivers 5V @ 2.5 amps which is exactly what is required. Replacing with a "bigger" (higher current capability) power supply won't make any difference on its own. Also there are different versions of the stock PSU and later ones are far less noisy in terms of radiated RFI. Ultimately the performance is limited by the internal voltage switching of the SB itself and that VFD which is a noisy component.

By the way, I'm happy to debate this point. I've measured the audio performance of the SB3 with different supplies. Have you?

This discussion is best conducted in the Audiophile Forum, where you will find lots of discussion on the pros and cons of expensive power supplies and other mods.

baardbaard
2010-02-10, 13:22
For heavens sake – can’t you read between the lines? There is more to powers supply design then current capability. That’s why some off us have abandon el-cheapo SMPS



By the way, I'm happy to debate this point. I've measured the audio performance of the SB3 with different supplies. Have you?


You really put a smile on my face with that on – I don’t have too. I have golden ears.

I started this thread with a simple question – could you please stay on topic?

DaveWr
2010-02-10, 13:35
I have golden ears.

I started this thread with a simple question – could you please stay on topic?

No you didn't, you started with a highly opinionated statement expressed as a fact, then you asked a question which has had an answer.

Phil has at least shown his results of comparison.

Dave

Phil Leigh
2010-02-10, 13:38
For heavens sake – can’t you read between the lines? There is more to powers supply design then current capability. That’s why some off us have abandon el-cheapo SMPS



You really put a smile on my face with that on – I don’t have too. I have golden ears.

I started this thread with a simple question – could you please stay on topic?

Golden something...

baardbaard
2010-02-10, 13:43
Oh boy - here we go again.

Phil Leigh
2010-02-10, 13:59
Oh boy - here we go again.

Post #5 - what do you mean "again"?

If you've come here for validation then you are in for a bunch of disappointment.

Look let's put the cards on the table. You bought the over-priced Welborne supply. Good for you. It will provide an improvement to the stock supply in terms of RFI/EMI picked up by nearby equipment. You could have achieved the same "improvement" with a mass-market PSU for about $20 - or a used medical grade PSU for about $40-$45 - which would be WAY better in every parameter you care to throw at it than the Welborne. If your nearby equipment is of good quality (which I assume it is) then it should be immune to RFI/EMI anyway.

Yes you can use it on the Touch. It will work fine. As does the stock supply.


... or are you one of those folks who believes that there is no such thing in audio terms as an SMPS that works fine?

I have a Touch. I've measured its audio performance against an SB3 with all manner of supplies (as have others on here).

I have learnt not to trust my "golden ears", especially when I have an investment to protect/justify.

ModelCitizen
2010-02-10, 14:12
The SB3 is packaged with a very wimpy and noisy switching power supply that inhibits its true potential.


Oh boy - here we go again.

Again? Not terribly surprising if you always start your threads with unqualified and opinionated statements like this one.

MC

baardbaard
2010-02-10, 14:56
If you've come here for validation then you are in for a bunch of disappointment.

Almost as nice as mine opening…



Look let's put the cards on the table. You bought the over-priced Welborne supply. Good for you. It will provide an improvement to the stock supply in terms of RFI/EMI picked up by nearby equipment. You could have achieved the same "improvement" with a mass-market PSU for about $20 - or a used medical grade PSU for about $40-$45 - which would be WAY better in every parameter you care to throw at it than the Welborne. If your nearby equipment is of good quality (which I assume it is) then it should be immune to RFI/EMI anyway.

Of course – almost any linear PS is adequate, and is an upgrade over El-cheapo SMPS. But I’m familiar with Ron W. works as I have owned some his previous tube designs. So what the heck – I pay the price.



Yes you can use it on the Touch. It will work fine. As does the stock supply.
Good




... or are you one of those folks who believes that there is no such thing in audio terms as an SMPS that works fine?
No – my home theater setup contains off Meridian and ICE-power from B&O – it works.



I have a Touch. I've measured its audio performance against an SB3 with all manner of supplies (as have others on here).

I have learnt not to trust my "golden ears", especially when I have an investment to protect/justify.

I ‘am engineer with an eye on the meter but I have learned to trust my ears.

RadioClash
2010-02-10, 20:07
Most of us are with you Baard. We know what we hear. We've just learned over the years on this forum that there is no sense in arguing with a brick wall.

Mnyb
2010-02-10, 21:57
Is this not 100% troll posts ? the OP's manner is very troll like.

Anyway, this is little off topic.

Don't do business with wellbourne he is con artist and have ripped off many people, including me.
When business is bad hes just taking your money and do not deliver products, after a while when you emailed he lies and says it's on it's way but don't produce any tracking number for the parcel. Later hes just stops answering your emails and keeps your money. This is from personal experience.
Google on wellbourne and you see.

A linear ps can also be had from Channel Island Audio CIA .

http://www.ciaudio.com/

Anyway what phill is telling anyone who want's listen is that there is a bunch of other switching power supplies DC/DC converters inside the SB3 practically rendering the quality from the outside ps and non issue.
Unless like the old 230V EU ps, you get secondary problems from it that leaks in to your other audio equipment, that is way this can influence thing (but not so much the SB3 itself).

If one cares to look at the diy forum, there is a people who actually understand the consequence and have taken out the soldering iron and extensively modified both the SB3 and SBR and replaced the internal supplies with linear supplies, thats more like a hobby but properly done it would yield some results then a more silent external 5V supply is a necessity.

baardbaard
2010-02-11, 04:54
Most of us are with you Baard. We know what we hear. We've just learned over the years on this forum that there is no sense in arguing with a brick wall.

Thanks – so there are some fellow music lovers here. We have to do something about the brick wall :-)

baardbaard
2010-02-11, 05:58
Anyway, this is little off topic.

Don't do business with wellbourne he is con artist and have ripped off many people, including me.
When business is bad hes just taking your money and do not deliver products, after a while when you emailed he lies and says it's on it's way but don't produce any tracking number for the parcel. Later hes just stops answering your emails and keeps your money. This is from personal experience.
Google on wellbourne and you see.

Agree this way OT.

I’ am aware off Ron W’s dubious reputation – but dont want to comment this any further other then he had some amazing SE amplifiers.



A linear ps can also be had from Channel Island Audio CIA .
http://www.ciaudio.com/


Nope - from previous info in this thread this PS is not a adequate to Touch. Lack of current drive.



Anyway what phill is telling anyone who want's listen is that there is a bunch of other switching power supplies DC/DC converters inside the SB3 practically rendering the quality from the outside ps and non issue.
Unless like the old 230V EU ps, you get secondary problems from it that leaks in to your other audio equipment, that is way this can influence thing (but not so much the SB3 itself).

Would like to comment that with an analogy:
Audiophiles love wires. Most off us have el-cheapo internal wire in our speakers, but we still have quit expensive speaker cables because it makes a difference.

In the physics and engineering department it's easy to develop a certain intellectual arrogance when it comes to understanding hi-fi. I doubt many physics professors would accept the fact that interconnect and loudspeaker cabels have any impact on sound quality.

The same picture regarding external PS and internal DC/DC converters

Mnyb
2010-02-11, 06:58
The CIA PSU would probably work under certain circumstances.

Touch can also feed 5V trough it's USB port, and then it can power a 2,5" hardisc that don't have any external PSU .

So if one don't ever connect any thing that needs a lot of power on the USB
I don't think all that 3 amps is needed, so a 2,5 psu might do it.
I can not guarantee, I will try when(If) i get my Touch.If the blue smoke gets out I will of course make a fool of myself on this forum asap .
I have a cia psu already, feeding my SB3.

Also I will provide my own server and will not be using the one that can be used on-board the Touch.

Anyone knowing the typical power drain sans externel drive and not running with the internal server.

Ianmac
2010-02-11, 13:50
Thanks – so there are some fellow music lovers here. We have to do something about the brick wall :-)

I am an irregular poster on this forum for exactly this reason - a brick wall attitude.
I have built a number of Linear power supplies for squeezebox and to my and at least another dozen peoples ears they make a difference.

Very few of us have access to the equipment to measure the output of squeezebox particularly the jitter on the SPdif.
We can only rely on our ears and the resolution of our hi fi systems to reproduce the benefits of any change.

Ianmac

baardbaard
2010-02-13, 02:55
If you've come here for validation then you are in for a bunch of disappointment.

You bought the over-priced Welborne supply. Good for you....

So who are you guys to criticize me and other for hearning that PS make a difference? I think you guys have to work with your attitude. I can’t se why my opening statement possible couldn’t have offended you when you read what other well regarded web sites write about this issue.


"We replace the noisy, switching power supply with a large, linear power supply.”
http://www.computeraudiophile.com/bolder-cable-company-squeezebox-duet-review.htm

”First, the stock switching power supply is woefully inadequate for the critical listening that we audiophiles do.”
http://www.enjoythemusic.com/magazine/equipment/1205/slimdevices_squeezebox.htm

When I moved from the standard SMPS (that is supplied with the SB3) to my DIY linear PSU, I could clearly hear a difference in the sound, despite only using the SB3 as a digital transport.
http://www.tnt-audio.com/accessories/phsb3_psu_e.html

mlsstl
2010-02-13, 08:53
So who are you guys to criticize me and other for hearning that PS make a difference? I think you guys have to work with your attitude.

I see precious little difference between your opening snipe and the "attitude" problem you accuse others of having.

And, since you started the thread, I think it is fair to say you set the tone of the discussion.

Basically your position seems to be that it is OK for you to be catty and snide about the issue but it isn't right that others use a similar tone if they happen to disagree with you. Just another variant of the "free speech for me but not for thee" theme that is ever popular.

It just gets back to the never-ending dispute between certain camps in the audiophile world.

I've tried different power supplies with my SB3 and found no difference I could detect. Guess that means my system or my ears "aren't resolving enough."

;-)

baardbaard
2010-02-13, 14:32
I give up - you win.

Now to something else - I contacted Paul Hynes this morning and ordered his SR3-05.
http://www.paulhynesdesign.com/index.html

"The SR3-05 can supply 5 volts at 3 amps. It is also my best power supply for the SB3/Touch for musical enjoyment"

For the rest off you - I will get back for a short review/comments.
It will take some time, the build schedule is currently 24 working days.

h.rav
2010-02-13, 14:57
^ do you have or can you find any measurements done that show a 'superior' power supply improves the Squeezebox' SQ?

baardbaard
2010-02-13, 15:05
^ do you have or can you find any measurements done that show a 'superior' power supply improves the Squeezebox' SQ?

paul@paulhynesdesign.com will be glad to tell you...

h.rav
2010-02-13, 15:08
^ I want to see an independent test, not from a manufacturer.

baardbaard
2010-02-13, 15:33
Contact Ben Duncan, at Ben Duncan Research
http://www.benduncanresearch.com/

BD-UK@dial.pipex.com

He wil be glad to help you out.

iwannatouch
2010-02-14, 10:20
I'm sure I'd hear a difference if I spent $300 for a power supply.

Phil Leigh
2010-02-14, 10:47
So who are you guys to criticize me and other for hearning that PS make a difference? I think you guys have to work with your attitude. I can’t se why my opening statement possible couldn’t have offended you when you read what other well regarded web sites write about this issue.


"We replace the noisy, switching power supply with a large, linear power supply.”
http://www.computeraudiophile.com/bolder-cable-company-squeezebox-duet-review.htm

”First, the stock switching power supply is woefully inadequate for the critical listening that we audiophiles do.”
http://www.enjoythemusic.com/magazine/equipment/1205/slimdevices_squeezebox.htm

When I moved from the standard SMPS (that is supplied with the SB3) to my DIY linear PSU, I could clearly hear a difference in the sound, despite only using the SB3 as a digital transport.
http://www.tnt-audio.com/accessories/phsb3_psu_e.html

The mere fact that you just had to come back one more time on this tells its own story.

You said you were an engineer? - try some engineering then, instead of putting faith in dubious magazine articles and even more dubious internet links.

Prove your replacement supply improves the audio replay quality... or even that it changes it in a truly noticeable way.

Does Paul Hynes actually have a Touch and has he actually tested his regs with it? - I hope so because anyone claiming a blanket improvement over "SB3/Touch" as if they were similar had better have actually tested that. The two devices are very different - especially in terms of the areas that might be improved by the PSU!

As for Ben Duncan - someone whose work I have studied over the last 30 years - I doubt he would make such claims unless he actually had a Touch and had tested it.

Stop trolling and provide some FACTS.

baardbaard
2010-02-15, 00:53
Let’s look into some measurements with audible effect – from John Atkinson:

The Squeezebox's frequency response (fig.1) showed a slight shelving-down at low frequencies that might just be audible given the wide range covered. (this has nothing to do with SMPS).

Now to something that may be effected by the minuscule wall-wart.:

Fig.2 shows the spectrum of the Squeezebox's analog output analyzed with a swept 1/3-octave bandpass filter while it decoded dithered data representing a 1kHz tone at –90dBFS. The traces are free from both power-supply and harmonic-distortion spuriae and peak at –90dBFS, suggesting good DAC linearity. The right-channel trace has some energy peaks centered on 9kHz and 18kHz, but these are low in level. Both channels also have a small energy peak evident at 30Hz, and the overall noise floor is 10–20dB higher in the midrange and bass than with the best 16-bit playback devices.

Summarize:
…the Squeezebox measures very well. Its noise floor is higher than that of good CD players.

Phil Leigh
2010-02-15, 01:45
Let’s look into some measurements with audible effect – from John Atkinson:

The Squeezebox's frequency response (fig.1) showed a slight shelving-down at low frequencies that might just be audible given the wide range covered. (this has nothing to do with SMPS).

Now to something that may be effected by the minuscule wall-wart.:

Fig.2 shows the spectrum of the Squeezebox's analog output analyzed with a swept 1/3-octave bandpass filter while it decoded dithered data representing a 1kHz tone at –90dBFS. The traces are free from both power-supply and harmonic-distortion spuriae and peak at –90dBFS, suggesting good DAC linearity. The right-channel trace has some energy peaks centered on 9kHz and 18kHz, but these are low in level. Both channels also have a small energy peak evident at 30Hz, and the overall noise floor is 10–20dB higher in the midrange and bass than with the best 16-bit playback devices.

Summarize:
…the Squeezebox measures very well. Its noise floor is higher than that of good CD players.
Great.
The noise on the right-channel is likely to be related to the VFD, which is known to affect one channel more than the other. Some people can actually hear the VFD noise breaking through (with their amps at full blast).

If I am interpreting JA's graphs correctly, the average noise floor seems to be sitting between -105 to -110dB.

I'm not sure how that equates to "10–20dB higher in the midrange and bass than with the best 16-bit playback devices".

However, -100dB is quiet. You would have to have lots of gain and very sensitive speakers or very powerful amplifiers to be able to hear anything at that level.


If JA was to repeat his tests with a different PSU...

My tests show that the noise floor of the Touch is substantially below that of the SB3. In part this is explained by the absence of the VFD, but also by other circuit changes.

Direct null testing of the stock PSU vs a quiet linear and even with batteries on the SB3 show no differences above -90dB.

So it seems that the noise floor performance is being set by the SB3 itself not its supply.

I have been unable to measure any performance improvement simply by changing the PSU. I can't hear one either. I should point out that I did swap my SMPS for a linear some years ago but have since swapped it back as the SMPS uses a lot less electricity and I can't hear or measure any benefit.


With the Touch we are talking about a much lower internal noise floor (-20dB from memory) to begin with - and I still can't hear or measure any change in audio quality with different PSU's.

h.rav
2010-02-15, 01:53
^ Wow Phil, thanks for sharing your findings and info :)

goopie
2010-03-24, 03:09
I am trialling a King Rex Power Supply for the Squeezebox. It's made in China specifically for the Squeezebox. It's being passed around the local audio community for evaluation, a Beta test if you like, prior to it being released in Australia. I've read the various threads here on power supplies for the Squeezebox, so I'm aware of the different opinions.

I found the difference in sound between the Wallwart and the King Rex was immediate and dramatic. Distortion (unwanted sound) was clearly and substantially reduced with the King Rex. It's that simple. Often in audio you look for black and white, only to find grey. In my case the difference is starkly black and white.

I would urge anyone with a Squeezebox to try a different power supply for themselves. Don't be influenced by the opinions of self proclaimed experts. Trust your own ears. Mine are, at last, enjoying a gorgeous sound from my Squeezebox.

Phil Leigh
2010-03-24, 06:45
I am trialling a King Rex Power Supply for the Squeezebox. It's made in China specifically for the Squeezebox. It's being passed around the local audio community for evaluation, a Beta test if you like, prior to it being released in Australia. I've read the various threads here on power supplies for the Squeezebox, so I'm aware of the different opinions.

I found the difference in sound between the Wallwart and the King Rex was immediate and dramatic. Distortion (unwanted sound) was clearly and substantially reduced with the King Rex. It's that simple. Often in audio you look for black and white, only to find grey. In my case the difference is starkly black and white.

I would urge anyone with a Squeezebox to try a different power supply for themselves. Don't be influenced by the opinions of self proclaimed experts. Trust your own ears. Mine are, at last, enjoying a gorgeous sound from my Squeezebox.

Given that you've posted this in the Touch forum, are you testing this PSU with a Touch? - if not, what are you using? Are you judging the analogue outputs of a SB?

How do you assess that "Distortion(unwanted sound) was clearly and substantially reduced"?

What ancilliary equipment are you using?

Can you quote some examples of the music you used to assess the PSU?

goopie
2010-03-24, 22:48
There is no longer a Squeezebox Classic forum. This thread is about power supplies.

Phil Leigh
2010-03-24, 23:29
There is no longer a Squeezebox Classic forum. This thread is about power supplies.

There never was a Classic (or Transporter) Forum.
So, you are using an SB3?

shevans
2010-03-25, 04:13
I am trialling a King Rex Power Supply for the Squeezebox. It's made in China specifically for the Squeezebox. It's being passed around the local audio community for evaluation, a Beta test if you like, prior to it being released in Australia. I've read the various threads here on power supplies for the Squeezebox, so I'm aware of the different opinions.

I found the difference in sound between the Wallwart and the King Rex was immediate and dramatic. Distortion (unwanted sound) was clearly and substantially reduced with the King Rex. It's that simple. Often in audio you look for black and white, only to find grey. In my case the difference is starkly black and white.

I would urge anyone with a Squeezebox to try a different power supply for themselves. Don't be influenced by the opinions of self proclaimed experts. Trust your own ears. Mine are, at last, enjoying a gorgeous sound from my Squeezebox.

Absolutely, its all about what you can hear, not what figure are given by a piece of test equipment. If it sounds better to you and you are happy then no one should spoil your enjoyment.

I bought a TeddySB3 PSU, slightly modified to provide a higher current output so it will work with both the SB3 & Touch. With analogue and digital outputs the difference was hugh! Figures and facts are meaningless over the use of ears...

Phil Leigh
2010-03-25, 05:06
Absolutely, its all about what you can hear, not what figure are given by a piece of test equipment. If it sounds better to you and you are happy then no one should spoil your enjoyment.

I bought a TeddySB3 PSU, slightly modified to provide a higher current output so it will work with both the SB3 & Touch. With analogue and digital outputs the difference was hugh! Figures and facts are meaningless over the use of ears...

Ears are indeed a very good test tool.

Unfortunately, one's ears are somewhat hampered in this respect by one's brain.

The entire high-end audio industry is based on the idea that we hear what we want to hear...

shevans
2010-03-25, 05:23
Ears are indeed a very good test tool.

Unfortunately, one's ears are somewhat hampered in this respect by one's brain.

The entire high-end audio industry is based on the idea that we hear what we want to hear...


Just as the majority of the industry is also hung up on specifications :)

Phil Leigh
2010-03-25, 09:48
Just as the majority of the industry is also hung up on specifications :)

Not so much these days... the golden era of specs was the 70's

firedog
2010-04-02, 01:08
Ultimately the performance is limited by the internal voltage switching of the SB itself and that VFD which is a noisy component.



Phil-

I understand from this that you would agree that some of the commercial mods that alter the internal electrical supply/switching of the SB or Duet can improve the sound? Would the same theoretically be true of the Touch?

To Everyone Else-

Phil is human, so he might be wrong about some things or have his opinions colored by personal biases (like all of us).

However, unlike almost everyone else who posts at the forum, he has both the technical knowledge and test measurements to back up his opinions. For that reason alone, I'd give his opinions serious consideration.

If you read his posts carefully, you'll see that he is careful about his claims - he knows the difference between opinion and fact - and is also willing to acknowledge other opinions when they are fact based and not just speculation.

Phil Leigh
2010-04-03, 00:26
Phil-

I understand from this that you would agree that some of the commercial mods that alter the internal electrical supply/switching of the SB or Duet can improve the sound? Would the same theoretically be true of the Touch?

To Everyone Else-

Phil is human, so he might be wrong about some things or have his opinions colored by personal biases (like all of us).

However, unlike almost everyone else who posts at the forum, he has both the technical knowledge and test measurements to back up his opinions. For that reason alone, I'd give his opinions serious consideration.

If you read his posts carefully, you'll see that he is careful about his claims - he knows the difference between opinion and fact - and is also willing to acknowledge other opinions when they are fact based and not just speculation.

Erm - thanks Firedog.
Yes I absolutely believe that it is possible to improve the SB3/SBR by doing some serious mods to the power supply arragements within both units. The use of super regs, better clocks etc would make a difference that should be audible although ultimately the performance will be limited by the nature of the circuit and the dac chips used, the layout of the circuit boards and so on. I'm not sure

As John Swenson pointed out, the biggest gain with an external PSU replacement (but no internal mods) relates to the older style switching supply which is very noisy and whilst that noise doesn't appear to affect the sb3/sbr itself (hence my test results) it CAN impact the rest of your system. For that reason alone I would advise against using those older PSU's.
Ironically, the reason I ditched that particular PSU years ago was that it interfered with an AM radio elsewhere in the house...


Back to the Touch - The Touch circuit seems less of an evolution of the SB3/SBR and more of a brand new design. Certainly, the LCD is less noisy than the VFD of the SB3. However, I would expect that whilst the upgrading of INTERNAL supplies, clocks etc might bring benefits, I would also expect - theoretically - there to be less to be gained here - simply because the Touch appears better all round to begin with.

Again as John mentioned there appears to be something unusual about the design or implementation of the headphone driver circuit of the Touch that could be looked into - I haven't had time to investigate this yet but will do so.

Ultimately I think the Touch is pretty darned good as it stands. To really improve on it there is only one "mod" I would be interested in and that is the provision of a (switchable) external clock input, so that the Touch as a pure transport (via spdif) can be locked to a DAC with suitable clock out capability. This will deliver the lowest possible jitter.


Finally, returning to the original theme, the old noisy PSU's are easily replaced with new ones. However, people should really take a look at ALL the similar ones they might have in their houses:

1) any computer PSU
2) Routers/switches/hubs/modems etc
3) external disks

Although airborne rfi/emi is not easily dealt with (Faraday cages have low WAF imo), it is worth using decent mains filtration on any such devices.
Screened mains cables to your audio gear can help somewhat too as they can resist some of the rfi creeping back in after the filters.

Yes I am human, I do make mistakes etc. I frequent this forum for two reasons; to learn and to help others where I can.

Happy Easter
Phil

Kevin Haskins
2010-04-03, 12:22
People are still going to buy tweaked power supplies. Why? Because they are available and audio is an addiction. It needs no logic. :-)

fgj
2010-04-03, 13:50
Finally, returning to the original theme, the old noisy PSU's are easily replaced with new ones. However, people should really take a look at ALL the similar ones they might have in their houses:

1) any computer PSU
2) Routers/switches/hubs/modems etc
3) external disks

How can I see the difference between an old noisy SB3 PSU and a newer less noisy (standard) one?

Phil Leigh
2010-04-03, 22:14
How can I see the difference between an old noisy SB3 PSU and a newer less noisy (standard) one?

That's a good question, with no simple answer.
The recognised methods are:

1) use an RF/EMI sniffer - I have one that was made by Russ Andrews years ago but I don't know if they still sell them. It works somewhat like those DIY tools for locating pipes and wires in walls... It is very sensitive.

2) use an old AM radio tuned between stations (not as good as option 1) - this method can detect supplies that are spewing out rf

3) Use a battery-powered oscilloscope to look directly at the mains - this option is for experts ONLY, is dangerous and requires specialised equipment: see here:
http://www.marcspages.co.uk/pq/4120.htm

4) Ears! - replace suspected device with a known clean supply (I have a Lab supply with adjustable voltage and current for this purpose) and see if the sound of your system changes.