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That is a good point..
I bought the topping p50 which was made specifically for my Dac and it was about $100 less than the Dac. If I hear no improvement I will send it back and get something else...
Toppings website shows the Dac sitting right on top of the lps. And does say something about interference and the chassis being designed to accommodate that
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No, this issue is not about whether that piece of chunky metallic object broadcasting EMI or not.
 
The issue is about what it does to surrounding audio components just by sitting there nearby in close proximity and not even plugged in and powered up.
 
Every damn piece of hi-fi components  we have in our system has to process complex audio signals, which are made up of fast-moving mixtures of level, frequency and dynamic range. These signals when passing along a wire, a circuit layout or through a component will have certain electrical properties, thus creating magnetic fields in their wake. 

These magnetic fields generate new fields by interacting with nearby and unnecessary metallic objects, (a phenomenon known as eddy current) resulting in interference. Sonically this translates into dynamic compression, shrunkened soundstaging, and bloated lower mid-bass "thump", mid and high timbre hardness.
 
Magnetic field interference does diminish with distances, however.
 
Power amps by themselves generate the strongest magnetic fields. So a piece of metallic object sitting next to it will cause a even more adversary interference than being placed next to a pre-amp, a cd player, or a dac. Still, it is advisable not to place any extraneous and unnecessary metallic objects next to the lower current hungry equipments.
 
And we had not even began to touch upon the instances when these LPS are powered up yet!
 
Anyway, to avoid this issue with LPS, try custom making a longer umbilical cord so that it can be placed further distances away from the audio components that it is required to feed. 
From drop (mass drop) about the p50 lps

This power supply is made from a solid aluminum brick that provides better mechanical strength and facilitates anti-interference performance. It’s also equipped with a toroidal transformer that has little magnetic leakage and excellent noise suppression. Three TPS7A4700 low-noise linear regulators further reduce noise. Set the power to either 110V or 230V and power your Topping DAC the right way with the P50
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2 hours ago, anewmission said:


I bought the topping p50 which was made specifically for my Dac and it was about $100 less than the Dac. If I hear no improvement I will send it back and get something else...

 

 

Excellent!  :thumb:  That's the logical thing to buy for your DAC.  :)

 

2 hours ago, anewmission said:


Topping's website shows the Dac sitting right on top of the lps. And does say something about interference and the chassis being designed to accommodate that

 

 

1 hour ago, anewmission said:


This power supply is made from a solid aluminum brick that provides better mechanical strength and facilitates anti-interference performance. It’s also equipped with a toroidal transformer that has little magnetic leakage and excellent noise suppression. Three TPS7A4700 low-noise linear regulators further reduce noise. Set the power to either 110V or 230V and power your Topping DAC the right way with the P50

 

 

Jerome may have something (I've never experimented - so I can't comment).

 

So try it as per the Topping website (DAC sitting right on top of the LPS) ... and then try it Jerome's way - with the LPS as far away as you can get it from the DAC.

 

Listen, in each case, to "dynamic compression, shrunkened sound staging, bloated lower mid-bass "thump", and mid and high timbre hardness ".

 

Andy

 

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Jerome may have something (I've never experimented - so I can't comment).
 
So try it as per the Topping website (DAC sitting right on top of the LPS) ... and then try it Jerome's way - with the LPS as far away as you can get it from the DAC.
 
Listen, in each case, to "dynamic compression, shrunkened sound staging, bloated lower mid-bass "thump", and mid and high timbre hardness ".
 
Andy
 
I will plug the Dac directly into the power amp and I'll try it with two different sets of speakers. That way I can be more certain.
Still trying to work out whether to use the volume control on the Dac or set it to full or whether to use the stepped attenuators on the power amp or set them to full. People have different opinions on this.
Not sure how the Dac is controlling volume but the power amp uses alps black beauties. So probably set the Dac to full and control via the black beauties?
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1 minute ago, anewmission said:

I will plug the Dac directly into the power amp and I'll try it with two different sets of speakers. That way I can be more certain.
Still trying to work out whether to use the volume control on the Dac or set it to full or whether to use the stepped attenuators on the power amp or set them to full. People have different opinions on this.
Not sure how the Dac is controlling volume but the power amp uses alps black beauties. So probably set the Dac to full and control via the black beauties?

A DAC drops bits to reduce volume.  Whether people can hear the difference is debatable, depends on source, DAC chip & implementation and people's ability to discern differences.  Ideally, set DAC to full.  

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6 minutes ago, anewmission said:

till trying to work out whether to use the volume control on the Dac or set it to full or whether to use the stepped attenuators on the power amp or set them to full. People have different opinions on this.
Not sure how the Dac is controlling volume but the power amp uses alps black beauties. So probably set the Dac to full and control via the black beauties?

I just got my hands on the D50, the Volume control toggle is crap, I think using the power amp with the black beauty is the way to go. D50 volume control is just too small! I like digital volume control people might think it looses resolution but it's just so much more accurate.
 

Do you find the D50 bass hasn't got enough oomph ? Might be because my current DAC (gustard x-20) has more gain but the bass seems fuller.

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2 minutes ago, Snoopy8 said:

A DAC drops bits to reduce volume.  Whether people can hear the difference is debatable, depends on source, DAC chip & implementation and people's ability to discern differences.  Ideally, set DAC to full.  

Nothing is ever that simple, and the bit stripping is misunderstood by most people. DACs usually operate in 32 bit space even if only working with 16 bit sources. Dropping bits from 192dB provided by 32bits in software is not a problem when it comes out the other side. Some DACs work best at a volume lower than maximum as well, depending on implementation, and often have lower noise around the -12 to -15dB mark. Potentiometers add noise the lower you go in volume, but stepped attenuators have equal noise at all levels. I use digital volume control in my system and bypass my preamp's potentiometer volume control because it sounds cleaner. As always, it's implementation dependent and auditioning the alternatives is the best course of action for him.

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11 hours ago, anewmission said:

I will plug the Dac directly into the power amp and I'll try it with two different sets of speakers. That way I can be more certain.

 

When one pair of speakers is playing, the other pair should be moved out of the room. If not, you will need to short the positive and negative input terminals of that unused speakers to minimize the adversary effects.

 

Again, it is magnetic field interference, ... (from that pair of unused speakers)

Edited by jeromelang
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10 hours ago, Ittaku said:

Nothing is ever that simple, and the bit stripping is misunderstood by most people. DACs usually operate in 32 bit space even if only working with 16 bit sources. Dropping bits from 192dB provided by 32bits in software is not a problem when it comes out the other side. Some DACs work best at a volume lower than maximum as well, depending on implementation, and often have lower noise around the -12 to -15dB mark. Potentiometers add noise the lower you go in volume, but stepped attenuators have equal noise at all levels. I use digital volume control in my system and bypass my preamp's potentiometer volume control because it sounds cleaner. As always, it's implementation dependent and auditioning the alternatives is the best course of action for him.

Not at all surprised that the digital volume control on your system is excellent and you prefer it. But not everyone has the calibre of your DAC. I preferred the Primaluna preamp over digital volume on the DAC.

 

Not so sure that DACs usually operate in 32 bit space. I thought there are still many on 24 bits?

 

Agree it comes down to the implementation in the components in one's setup and an audition is the only way to find out what is better.

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8 minutes ago, Snoopy8 said:

Not at all surprised that the digital volume control on your system is excellent and you prefer it. But not everyone has the calibre of your DAC. I preferred the Primaluna preamp over digital volume on the DAC.

 

Not so sure that DACs usually operate in 32 bit space. I thought there are still many on 24 bits?

 

Agree it comes down to the implementation in the components in one's setup and an audition is the only way to find out what is better.

It's actually the volume control in my DSP device feeding into the DAC, not the DAC itself. My DAC fortunately has a recommended volume setting for when it's used with a preamp which interestingly is 8dB down from its maximum volume so I leave that there. I wish more DACs with volume control were as explicit with such information. DSP is all done in 32 bit space on most DACs out there. The 24 bits is the resolution they can cope with, but the calculations for oversampling, filtering, and volume control are virtually always 32 bits (some even more.) Pretty much any device that can do 24 bits will be operating internally in 32 bits. Devices that can only cope with 16 bits are the exception, and they're very uncommon these days. Stripping bits when you only start with 16 will for sure come at a quality cost.

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21 minutes ago, Ittaku said:

It's actually the volume control in my DSP device feeding into the DAC, not the DAC itself. 

Wow, didn't know the X4 was that good.

 

I did investigate it, ironically for its digital volume control. Wanted it to control digital volume on optical out and simultaneously on XLR out to subs. Too late now but maybe it could have worked?

Edited by Snoopy8
Typo
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3 minutes ago, Snoopy8 said:

Wow, didn't know the X4 was that good.

 

I did investigate it, ironically for its digital volume control. Wanted it to control digital volume on optical out and simultaneously on XLR out to subs. Too late now but maybe it could have worked?

That's almost exactly how I use it. The X4 is exceptional, and only the firmware quirks have annoyed me since I bought one when they were still very new, but most seem under control now. The combination of crossover, preamp, dsp room control ( at native sample rate - a one of a kind in the hardware dsp room control space), and a very good ADC/DAC, makes it easily worth its 5k and more.

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Nothing is ever that simple, and the bit stripping is misunderstood by most people. DACs usually operate in 32 bit space even if only working with 16 bit sources. Dropping bits from 192dB provided by 32bits in software is not a problem when it comes out the other side. Some DACs work best at a volume lower than maximum as well, depending on implementation, and often have lower noise around the -12 to -15dB mark. Potentiometers add noise the lower you go in volume, but stepped attenuators have equal noise at all levels. I use digital volume control in my system and bypass my preamp's potentiometer volume control because it sounds cleaner. As always, it's implementation dependent and auditioning the alternatives is the best course of action for him.
Probably the wrong place to ask this, but if that is the case of pots vs stepped, could I potentially replace the pots in my guitar to stepped attenuators?
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1 minute ago, anewmission said:

Probably the wrong place to ask this, but if that is the case of pots vs stepped, could I potentially replace the pots in my guitar to stepped attenuators?

Yes? But most stepped attenuators are much bigger and bulkier than regular pots. I believe you can get some preformed ones that are relatively small though.

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Yes? But most stepped attenuators are much bigger and bulkier than regular pots. I believe you can get some preformed ones that are relatively small though.
These are about the same size as guitar pots,


https://www.ebay.com.au/i/201654895419?chn=ps&norover=1&mkevt=1&mkrid=705-139619-5960-0&mkcid=2&itemid=201654895419&targetid=538829682402&device=m&mktype=pla&googleloc=9071850&poi=&campaignid=6762456169&mkgroupid=79795395576&rlsatarget=pla-538829682402&abcId=578876&merchantid=119094115&gclid=EAIaIQobChMIz_j1v5-i5QIVlIqPCh1QaQwKEAkYASABEgIzn_D_BwE


Whether they are any good I don't know
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  • 8 months later...

I recently bought an MCRU linear power supply for my Clearaudio Concept turntable.  The unit was marketed as being suitable for Clearaudio turntables (although this may be just simply a voltage match for the turntable).

 

The unit is well made - and is obviously a good bit of kit.

 

Now, it may be that replacing a power supply for a turntable will not give you any noticeable sonic improvement when compared to, say, a preamp.

 

All I can say, after lots of A/B testing, is that there is no improvement whatsoever to the sound.  I consider myself to have a good ear, and I am using good mid-range equipment.

 

The only thing the MCRU brings to the table is a confidence that you’re using a good bit of kit.  That is all.  
 

If people notice a difference using one of these units in their set up, great; this is not a sweeping criticism of upgraded linear power supplies.  This is simply my experience with one used with a decent turntable, with a decent amp and speakers.

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On 16/10/2019 at 11:31 PM, Ittaku said:

Nothing is ever that simple, and the bit stripping is misunderstood by most people. DACs usually operate in 32 bit space even if only working with 16 bit sources. Dropping bits from 192dB provided by 32bits in software is not a problem when it comes out the other side. Some DACs work best at a volume lower than maximum as well, depending on implementation, and often have lower noise around the -12 to -15dB mark. Potentiometers add noise the lower you go in volume, but stepped attenuators have equal noise at all levels. I use digital volume control in my system and bypass my preamp's potentiometer volume control because it sounds cleaner. As always, it's implementation dependent and auditioning the alternatives is the best course of action for him.

I thought and had this belief,  the figures saids it all, I even used a NAD M51 dac that has 35bit volume control according to the advertised features and its possible very true that this is the case, then I experimented with digital volume control that’s supported by the dac chip: ESS chips that are usually advertised to be 32Bit,  and every time I find that the PGA 2310 volume control which is a digitally controlled analog chip is far better at low volumes...every time,  it maintains the and preserves the details at  low levels, so go figure!  

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2 minutes ago, Addicted to music said:

I thought and had this belief,  the figures saids it all, I even used a NAD M51 dac that has 35bit volume control according to the advertised features and its possible very true that this is the case, then I experimented with digital volume control that’s supported by the dac chip: ESS chips that are usually advertised to be 32Bit,  and every time I find that the PGA 2310 volume control which is a digitally controlled analog chip is far better at low volumes...every time,  it maintains the and preserves the details at  low levels, so go figure!  

Like I said, it's implementation dependent and auditioning is the best option rather than coming to a conclusion based on the technology.

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On 10/07/2020 at 4:58 AM, Darkstarr666 said:

 

Now, it may be that replacing a power supply for a turntable will not give you any noticeable sonic improvement when compared to, say, a preamp.

 

All I can say, after lots of A/B testing, is that there is no improvement whatsoever to the sound.  I consider myself to have a good ear, and I am using good mid-range equipment.

 

 

Yes, it's hard to believe that merely changing the power supply to a TT motor speed controller can make a difference to the sound.  :o

 

But all I can do is recount the experience when I (and my trusted listening panel) listened to 5 different power supplies for my 'Number9' motor speed controller (for AC motors).

 

It comes as standard with a 48v Meanwell SMPS.  The SQ with the 5 alternatives, in our unanimous opinion - in 'better' order - was:

  1. 48v Meanwell
  2. 48v linear PS
  3. SLAs - 4x 12v SLAs stacked together to give 48v ... with a second quadruple stack in parallel, to lower ESR
  4. linear PS with an isolating transformer between it and the wall socket
  5. Meanwell with an isolating transformer between it and the wall.

 

Power always make a difference!  :)

 

Andy

 

Edited by andyr
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Cheap SMPS do not have very good noise filtering and shielding. The better SMPS's have filters on the output and are well shielded. Adding LC filters to output of cheap eBay SMPS does make a huge difference, especially in a amplifier that has poor PSSR. I ran my power amps with cheap eBay SMPS, output filtering was in the power supply case consisting of large inductors to filter the 48kHz. Then inside the power amp case LM317's were used to further filter the supply lines. After 2 LM317's total noise was attenuated by 18dB, and best of all NO mains noise, residual noise was way out of the audio band.

 

SMPS's are used extensively on fighter jets although milspec are much higher switching frequency. The higher the switching frequency the easier it is to filter the noise, ie smaller inductors and caps.

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17 minutes ago, Warren Jones said:

SMPS's are used extensively on fighter jets although milspec are much higher switching frequency. The higher the switching frequency the easier it is to filter the noise, ie smaller inductors and caps.

You would expect they would be like the holy grail to fighter jets. Less overall weight and better efficiency.

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