This is what I was talking about:
This is a LCAudio XO2 with a seperate PSU.
An externally hosted image should be here but it was not working when we last tested it.
This is a LCAudio XO2 with a seperate PSU.
-------------------------------------------------Tazzy said:
I have one. The raw ps gives some 29V on a 240V supply. I had to change the transformer!
Tazzy said:
Hi
In short: Yes, there is a supply now. Choke input, so true sine wave load for transformer. 5 years warrantee, 99 euro
Soundwise my first impression is that realism gains, and low level resolution as well. Sold many already.
To be honest, price wise my clock is the best investment, but as usual, small steps for the last bit cost some extra too.
all the best
Attachments
In short: Yes, there is a supply now. Choke input, so true sine wave load for transformer. 5 years warrantee, 99 euro
Soundwise my first impression is that realism gains, and low level resolution as well. Sold many already.
------------------------------------------------------
For European and North American vendors using small pcb transformers - warning for the UK.
The supply voltage here can be 257V whatever they say. Supply companies like this as consumption is proportional to V squared.
I have had many pcb transformers give ridiculous voltages; notably 29V dc from a LC Clock ps. The caps are only 25V.
Soundwise my first impression is that realism gains, and low level resolution as well. Sold many already.
------------------------------------------------------
For European and North American vendors using small pcb transformers - warning for the UK.
The supply voltage here can be 257V whatever they say. Supply companies like this as consumption is proportional to V squared.
I have had many pcb transformers give ridiculous voltages; notably 29V dc from a LC Clock ps. The caps are only 25V.
Originally, the UK mains voltage supply was specified at 240V RMS +/-6%. Some while ago, the specifications were changed (230V +10%, -6%) to allow hamonisation across Europe.
This implies a peak voltage of 253V, rather than the 257V quoted above.
In many cases though the electricity suppliers own standards are considerably tighter than this, for variation over a 24hr period.
But as usual, worst case design applies. It's rarely the transformer that's a problem though, the dissipation in reg's and safety margins on capacitor working voltages are far more critical.
Andy.
This implies a peak voltage of 253V, rather than the 257V quoted above.
In many cases though the electricity suppliers own standards are considerably tighter than this, for variation over a 24hr period.
But as usual, worst case design applies. It's rarely the transformer that's a problem though, the dissipation in reg's and safety margins on capacitor working voltages are far more critical.
Andy.
Fmak,
That's simply not true. Seeboard, for example, recently monitored a colleagues supply after he complained - it exceeded their allowable variations in a given time period, which were more stringent than the legal limits. This is in SE UK (Tunbridge Wells).
In my colleagues case, they've just dug up his drive and installed a new supply cable. You are likely to find them more helpful than you think. That 257V reading, if true, is wrong and they are legally bound to do something about it.
I believe also, like Gas, it's people like Seeboard responsible for the infrastructure, irrespective of what company you actually buy your electric from.
They do take this stuff seriously, but first, make sure your meter is calibrated, the first thing they will do is perform a simple comparative measurement to check the validity of your claim.
Andy.
That's simply not true. Seeboard, for example, recently monitored a colleagues supply after he complained - it exceeded their allowable variations in a given time period, which were more stringent than the legal limits. This is in SE UK (Tunbridge Wells).
In my colleagues case, they've just dug up his drive and installed a new supply cable. You are likely to find them more helpful than you think. That 257V reading, if true, is wrong and they are legally bound to do something about it.
I believe also, like Gas, it's people like Seeboard responsible for the infrastructure, irrespective of what company you actually buy your electric from.
They do take this stuff seriously, but first, make sure your meter is calibrated, the first thing they will do is perform a simple comparative measurement to check the validity of your claim.
Andy.
I believe also, like Gas, it's people like Seeboard responsible for the infrastructure, irrespective of what company you actually buy your electric from.
They do take this stuff seriously, but first, make sure your meter is calibrated, the first thing they will do is perform a simple comparative measurement to check the validity of your claim.
---------------------------------------------
My meters are correct; are you offering to get thru' to my Folkestone supplier for me? I don't have the time to spend an hour being pinged from one phone to another. and then tols it's out of hours.
They do take this stuff seriously, but first, make sure your meter is calibrated, the first thing they will do is perform a simple comparative measurement to check the validity of your claim.
---------------------------------------------
My meters are correct; are you offering to get thru' to my Folkestone supplier for me? I don't have the time to spend an hour being pinged from one phone to another. and then tols it's out of hours.
The noise level can be a red-herring too - the error amp I use in my clock supply has a high noise corner, relative to the audio band, but sounds better than a much quieter audio type amp in this application. The noise spectra is very important and may not be universally applicable between applications.
------------------------------------------------------------------
I have been reducing the noise level in my 5V clock supply over a bandwidth iof 1 MHz and conducting listening tests thru' a 24/96 ADC, fed back into a dac, using analogue signals.
At 60 nV/sqrtHz, the sound was somewhat digital compared to my analogue source thru a passive preamp. At 10 nV/sqrtHz, the sound was much improved as I described elsewhere; much more relaxed without loosing detail but still different from my source. At 5 nV/sqrtHz, I am rather close to the sound of the source. The noise spectra are very clean, with a crest factor of about 1.6 .
So noise injection thru' the clock seems quite important. I am now talking about -110 dB or more of isolation.
A battery ps didn't cahnge anything
------------------------------------------------------------------
I have been reducing the noise level in my 5V clock supply over a bandwidth iof 1 MHz and conducting listening tests thru' a 24/96 ADC, fed back into a dac, using analogue signals.
At 60 nV/sqrtHz, the sound was somewhat digital compared to my analogue source thru a passive preamp. At 10 nV/sqrtHz, the sound was much improved as I described elsewhere; much more relaxed without loosing detail but still different from my source. At 5 nV/sqrtHz, I am rather close to the sound of the source. The noise spectra are very clean, with a crest factor of about 1.6 .
So noise injection thru' the clock seems quite important. I am now talking about -110 dB or more of isolation.
A battery ps didn't cahnge anything
Tazzy said:
Hi
I did not do a 1:1 comparison, but the main issue is mains separation, so I suspect it will sound in the same range
I considered batteries but found this a more robust alternative for the average customer (i.e. not you out here on the forum)
regards
fmak said:
Ooops, but that still means about 27V at 230V+6%
1 - UK mains is too hight at your place
2 - Was the LC circuit loaded ?
all the best
fmax ps
I make a board to test Fmak's ps within Guido's XO clock.
First I had to solved some hum issues. Hum' source cames from the dedicated trafo I installed into the cd player.
I wanted to place the trafo very close to the XO's ps but, due to the player's circuitry, it had to be too close to the player output' stage.
As soon as I placed the trafo away from the output stage, hum dissapeared.
Before Fmak's ps I used the one by Cuno Snoeren (http://home.tiscali.nl/~t708955/schem/xoschema.jpg).
-Fmax measures on his ps has been comented already.
-To me, the main difference is: more resolution.
Now bad recordings are even worse, but good cd's show some details more explicitly.
Yesterday, I tested the results playing with two recordings.
With one of the best performances on Bach's BWV82 (Frans Brüggen/Max van Egmond) but really bad recorded by Sony: the original sybillances are even more prone, making it awfull.
Testing the cd edited by Clarity Records on Stravinsky's The rite of Spring, vocals and heavy bass are nearly perfect, I mean quite close to the sound of the concert hall.
I make a board to test Fmak's ps within Guido's XO clock.
First I had to solved some hum issues. Hum' source cames from the dedicated trafo I installed into the cd player.
I wanted to place the trafo very close to the XO's ps but, due to the player's circuitry, it had to be too close to the player output' stage.
As soon as I placed the trafo away from the output stage, hum dissapeared.
Before Fmak's ps I used the one by Cuno Snoeren (http://home.tiscali.nl/~t708955/schem/xoschema.jpg).
-Fmax measures on his ps has been comented already.
-To me, the main difference is: more resolution.
Now bad recordings are even worse, but good cd's show some details more explicitly.
Yesterday, I tested the results playing with two recordings.
With one of the best performances on Bach's BWV82 (Frans Brüggen/Max van Egmond) but really bad recorded by Sony: the original sybillances are even more prone, making it awfull.
Testing the cd edited by Clarity Records on Stravinsky's The rite of Spring, vocals and heavy bass are nearly perfect, I mean quite close to the sound of the concert hall.
230v... ha!
Here in Portugal the mains voltage was 220v.
Some years ago they "standardized" to 230v.
When I measure a mains plug at home I get from 236 to 239v.
You can imagine that PSU transformers and regulators on old gear (like my Philips CD650) get extremely
.
😱
Here in Portugal the mains voltage was 220v.
Some years ago they "standardized" to 230v.
When I measure a mains plug at home I get from 236 to 239v.
You can imagine that PSU transformers and regulators on old gear (like my Philips CD650) get extremely
.😱
I think it is more than some years ago that 220V became 230V as a standard in Europe. It is only a rise of 4.5 %. This didn't hurt transformers but it did hurt old bulbs ( lamps ). This was around 1989 or earlier in the Netherlands.
You're right about 220V gear that has to take 239V, that is a tad too much in some cases.
I always switch to 240V when the transformer has 240V primaries ( nearly all Philips cdplayers have a 240V tap ). I always check that with my measurement gear too as I once saw an Iwatsu 220V oscilloscope that died because of it. Pioneer PDS901 suffers from failure too when it has 230V on it for a longer time.
It is good practice to check the resulting voltages before the regulators after changing primaries to 240V !
You're right about 220V gear that has to take 239V, that is a tad too much in some cases.
I always switch to 240V when the transformer has 240V primaries ( nearly all Philips cdplayers have a 240V tap ). I always check that with my measurement gear too as I once saw an Iwatsu 220V oscilloscope that died because of it. Pioneer PDS901 suffers from failure too when it has 230V on it for a longer time.
It is good practice to check the resulting voltages before the regulators after changing primaries to 240V !
You're right about 220V gear that has to take 239V, that is a tad too much in some cases.
It is good practice to check the resulting voltages before the regulators after changing primaries to 240V ! [/B][/QUOTE]
-------------------------------------------------------
Power comapnies love higher voltages as comsuption is proportional to voltage squared.
I have found up to 257V in UK in three places in the SE of England. Everthing used to buzz here in London except for Japnese transformers until they carried out cable replacement and it is now 240V.
I had an LC Audio clock PS that gave 29V dv loadedto 50mA!
It is good practice to check the resulting voltages before the regulators after changing primaries to 240V ! [/B][/QUOTE]
-------------------------------------------------------
Power comapnies love higher voltages as comsuption is proportional to voltage squared.
I have found up to 257V in UK in three places in the SE of England. Everthing used to buzz here in London except for Japnese transformers until they carried out cable replacement and it is now 240V.
I had an LC Audio clock PS that gave 29V dv loadedto 50mA!
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