Hi Denis,
Many thanks
The Schottky's are doing their job "a very little bit" softer, but using the snubber this doesn't matter - the artifacts are gone. That's why - at least I - would recommend the LSIB-HPULN, as long as your device needs >9V and you have an application-matching transformer.
I will post some pictures comparing both power supplies (FFT) next week at my webshop.
Best regards
Stammheim
Many thanks
The Schottky's are doing their job "a very little bit" softer, but using the snubber this doesn't matter - the artifacts are gone. That's why - at least I - would recommend the LSIB-HPULN, as long as your device needs >9V and you have an application-matching transformer.
I will post some pictures comparing both power supplies (FFT) next week at my webshop.
Best regards
Stammheim
Hi Vitalica,
Many thanks for your feedback. I am happy you reached the improvement you wished!
sq225917, many thanks for your info, I've already seen the reg, but there are some reasons why I see a benefit going on with the positive reg LT3045:
- IMHO in most cases a negative voltage is needed, where a positive voltage is also present (corresponding) and which are both worth to upgrade. As an example I have DAC chips in my mind.
- Where a balanced power supply is needed, I'd always prefer a +- voltage with exactly the same characteristics, that's why I'd always try to use the same reg for that application (like one does with SD- or MD-HPULN for example).
And because I see that from my own experience only:
Where do you guys see a use for the negative reg only?
Best regards
Stammheim
Many thanks for your feedback. I am happy you reached the improvement you wished!
sq225917, many thanks for your info, I've already seen the reg, but there are some reasons why I see a benefit going on with the positive reg LT3045:
- IMHO in most cases a negative voltage is needed, where a positive voltage is also present (corresponding) and which are both worth to upgrade. As an example I have DAC chips in my mind.
- Where a balanced power supply is needed, I'd always prefer a +- voltage with exactly the same characteristics, that's why I'd always try to use the same reg for that application (like one does with SD- or MD-HPULN for example).
And because I see that from my own experience only:
Where do you guys see a use for the negative reg only?
Best regards
Stammheim
Hi everybody,
some might already have seen the Quasimodo-PCB at MPAudio...
Because avoiding transformer ringing is something underestimated IMHO, I'd like to tell you to get some info around Mark's Quasimodo-PCB (here at diyaudio for example) and it's great and easy way to get an anti-transformer-ringing solution for your HPULN-power supplies as well as for all your other applications, whereever a transformer is needed.
Best regards
Stammheim
some might already have seen the Quasimodo-PCB at MPAudio...
Because avoiding transformer ringing is something underestimated IMHO, I'd like to tell you to get some info around Mark's Quasimodo-PCB (here at diyaudio for example) and it's great and easy way to get an anti-transformer-ringing solution for your HPULN-power supplies as well as for all your other applications, whereever a transformer is needed.
Best regards
Stammheim
I bought two HPULN PSUs , which I use in my new DSD DAC. Sources have brought great improvement and I'm very pleased with the result. I plan to buy another source for the router
Hi Vitalica,
Those inter connects between boards which look like they have snap ins look interesting, could you post source of supply?
Nice build by the way!
PLEASE can you offer 12VAC for your 150VA transformer as well ?
AFAIK, the LSIB accepts max. 12VAC.
Would be very nice.
Thanks
Matt
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Hi Matt,
Generally answer: There's any voltage with any power rate available.
The transformers offered at the webshop are transformers, that are in stock, as these specs are used in common applications and are often ordered with the HPULN power supplies.
So unusual orders with power rates or output voltages like 4,2VAC or 7,8VAC are more often, then one assumes, to match the exact customer's desired voltage output.
So feel free to contact me with your wishes or questions. The chat-option is a quick and easy way, as well as contacting me via contact@mpaudio.net.
Matt, there's also a measurement shown at our FAQ showing the (voltage) performance using the LSIB-HPULN with a 14VAC transformer, further measurements with other voltages will follow. What I notice is that people are often unsure in choosing the right transformer voltage, having the heat and voltage headroom in mind, so it might be helpful to talk about the application's specs to find the right transformer.
Please keep in mind, that such orders are completely custom made transformers with an additional delivery time of 2-4 weeks for manufacturing.
Best regards
Stammheim
Generally answer: There's any voltage with any power rate available.
The transformers offered at the webshop are transformers, that are in stock, as these specs are used in common applications and are often ordered with the HPULN power supplies.
So unusual orders with power rates or output voltages like 4,2VAC or 7,8VAC are more often, then one assumes, to match the exact customer's desired voltage output.
So feel free to contact me with your wishes or questions. The chat-option is a quick and easy way, as well as contacting me via contact@mpaudio.net.
Matt, there's also a measurement shown at our FAQ showing the (voltage) performance using the LSIB-HPULN with a 14VAC transformer, further measurements with other voltages will follow. What I notice is that people are often unsure in choosing the right transformer voltage, having the heat and voltage headroom in mind, so it might be helpful to talk about the application's specs to find the right transformer.
Please keep in mind, that such orders are completely custom made transformers with an additional delivery time of 2-4 weeks for manufacturing.
Best regards
Stammheim
Hi Matt,
all transformers custom made transformers need to be cleared directly regarding VA and voltage output, that's why it's best to contact me directly. In this case I'd also tell you more about pricing and actual waitint time, as well I'd ask you if you have any questions regarding your application for example.
It's no mistery by the way... depending on your wishes there are additional costs of 4-10€ only per transformer in the category you see at the webshop. We also deliver transformers with >600VA for amplifiers, or 30VA for opamps for example. That's why I say let's talk directly to find a transformer that fits your needs...
Hi Gregje,
as support took to much time, the HPULN's are only for sell in complete, tested and preadjusted condition for a bunch of months now, sorry.
Best regards
Stammheim
all transformers custom made transformers need to be cleared directly regarding VA and voltage output, that's why it's best to contact me directly. In this case I'd also tell you more about pricing and actual waitint time, as well I'd ask you if you have any questions regarding your application for example.
It's no mistery by the way... depending on your wishes there are additional costs of 4-10€ only per transformer in the category you see at the webshop. We also deliver transformers with >600VA for amplifiers, or 30VA for opamps for example. That's why I say let's talk directly to find a transformer that fits your needs...
Hi Gregje,
as support took to much time, the HPULN's are only for sell in complete, tested and preadjusted condition for a bunch of months now, sorry.
Best regards
Stammheim
Any comments regarding this particular claim from someone's personal experience?
A novel way to massively improve the SQ of computer audio streaming - Page 442 - Music Servers - Computer Audiophile
A novel way to massively improve the SQ of computer audio streaming - Page 442 - Music Servers - Computer Audiophile
galvanic isolation of high impedance leakage current
I would assume it depends more on the user's implementation than on the HPULN regulator boards.
If the power transformer used is isolating - meaning the secondaries are isolated from the primary AC mains,
and the so called GND pin of the HPLUN is isolated from the AC mains ground, which the boards allow you to do,
then you have isolation, except for the very tiny transformer interwinding capacitance, which can be dealt with using shunt filter caps on the primary or secondary side, or preferably both sides.
Even for a sophisticated isolating PSU like the Ultracap LPS-1.2, there is a tiny amount of leakage due to the parasitic junction capacitance of the switching transistors used to connect/disconnect the 2 banks of ultracaps from the charging circuit. But this tiny leakage is effectively rendered insignificant by employing the JSGG ground shunt approach to stop 90% of the high impedance leakage noise from entering the DC side of the PSU.
If an R-Core transformer is used, the leakage is even tinier.
However, I stand ready to accept any better explanation.
I would assume it depends more on the user's implementation than on the HPULN regulator boards.
If the power transformer used is isolating - meaning the secondaries are isolated from the primary AC mains,
and the so called GND pin of the HPLUN is isolated from the AC mains ground, which the boards allow you to do,
then you have isolation, except for the very tiny transformer interwinding capacitance, which can be dealt with using shunt filter caps on the primary or secondary side, or preferably both sides.
Even for a sophisticated isolating PSU like the Ultracap LPS-1.2, there is a tiny amount of leakage due to the parasitic junction capacitance of the switching transistors used to connect/disconnect the 2 banks of ultracaps from the charging circuit. But this tiny leakage is effectively rendered insignificant by employing the JSGG ground shunt approach to stop 90% of the high impedance leakage noise from entering the DC side of the PSU.
If an R-Core transformer is used, the leakage is even tinier.
However, I stand ready to accept any better explanation.
Hi Michael,
there is another comment on the same page of the above mentioned CA forum:
Suspect output caps on big MPAudio regulator modules not good for best SQ, but not yet tested without. Hope someone test MPA module with output caps removed (maybe just 10mfd like app sheet?) to confirm/reject theory, before recommend for experiments for this thread.
Would you like to comment here or directly on CA forum?
Thanks
Matt
there is another comment on the same page of the above mentioned CA forum:
Suspect output caps on big MPAudio regulator modules not good for best SQ, but not yet tested without. Hope someone test MPA module with output caps removed (maybe just 10mfd like app sheet?) to confirm/reject theory, before recommend for experiments for this thread.
Would you like to comment here or directly on CA forum?
Thanks
Matt
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Hi Matt,
I already tried to go into conversation regarding HPULN's features at CA, but as a seller it's not desireable to discuss about own products at CA - this could be understood as advertisment, MPAudio must have a paid account in this case. My posts were deleted after seconds.
The HPULN's were made to match several needs / applications - they can supply a small chip, a circuit or a whole device with a high current need with audio application in focus.
There were plenty of capacitors tested to find the "right" output capacitor. In short, the polymer's were chosen because of following reasons:
- Tested with several devices and loads, the polymers had a great behaviour regarding transient response, what also was the reason to choose their capacity (depending on HPULN-format and number of reg's). Two in parallel also improved results, even if absolutely marginal.
- Listening and comparing "music reproduction", which is an objective thing measuring supplied device's output, and a subjective perception while listening music. From the experience made, devices like DAC's benefit from the output capacity >10uF per LT (Please also keep in mind, that "a minimum of 10uF" is written in the datasheet).
By the way... the HPULN's were also tested with several (also "fancy" - don't get me wrong, I really like some of them) film capacitors - with a partially similar result, but with a huge difference in necesary additional pcb- area and costs.
Nevertheless... music is subjective - there always are different favours. That's why I'm looking forward to learn more about people's experience with capacitors.
Best regards
Stammheim
I already tried to go into conversation regarding HPULN's features at CA, but as a seller it's not desireable to discuss about own products at CA - this could be understood as advertisment, MPAudio must have a paid account in this case. My posts were deleted after seconds.
The HPULN's were made to match several needs / applications - they can supply a small chip, a circuit or a whole device with a high current need with audio application in focus.
There were plenty of capacitors tested to find the "right" output capacitor. In short, the polymer's were chosen because of following reasons:
- Tested with several devices and loads, the polymers had a great behaviour regarding transient response, what also was the reason to choose their capacity (depending on HPULN-format and number of reg's). Two in parallel also improved results, even if absolutely marginal.
- Listening and comparing "music reproduction", which is an objective thing measuring supplied device's output, and a subjective perception while listening music. From the experience made, devices like DAC's benefit from the output capacity >10uF per LT (Please also keep in mind, that "a minimum of 10uF" is written in the datasheet).
By the way... the HPULN's were also tested with several (also "fancy" - don't get me wrong, I really like some of them) film capacitors - with a partially similar result, but with a huge difference in necesary additional pcb- area and costs.
Nevertheless... music is subjective - there always are different favours. That's why I'm looking forward to learn more about people's experience with capacitors.
Best regards
Stammheim
Followed by:
" Nonetheless, larger values of output capacitance do decrease peak output deviations during a load transient."
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Hi Michael,
can you try to describe how your 5A LS-HPULN sounds powering a DAC?
Further, when I increase the VA rating of the transformer it sounds better to my ears. I use 250VA transformers for my preamps. What is your experience?
Thanks
Matt
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Hi Matt,
to be honest I'm not sure what to answer regarding your first question, beside the feedback from users and customers in this thread. There are so many devices / DAC's in different setups, that I can't give a generally valid answer, what exactly a HPULN is able to "change".
Watch out: Following is my personal experience, if you'd force me to give an answer on your risk. One else can have an own opinion
If the reader doesn't accept other opinions, please stop reading here (and work on your "bias").
As I personally use the HPULN's in several own applications to power DAC's, preamps or even amps, I can tell that my first impression always is: silence.
Well, no, of course there is music
But in a silent-cleaner way. As loud, as it was before of course. Just more focussed on the track that I wanna listen to.
I never gave a personal explenation here. Music is subjective and I don't want people to get briefed, as from my experience there always were test-auditors that heared something else improved / changed, then the others did.
Regarding your second question:
My first thought was: Wow, 250VA for a circuit that needs few hundreds mA only.
My second was: Were that exactly the same transformers with different power rate only or were there other aspects, that could give you an improved perception using that oversized transformer?
What I also thought about is, that most of commercial AVR's have a power rate twice of your preamp. But for supplying up to 11 amplifiers. That's also not a cut in your direction.
But hey, honestly:
We hear differences between several capacitors (that is NOT a cut on the previous topic!!!), no matter if they are in a signal path or in a power supply. Or differences between power or speaker cables. So why not using the 250VA transformer for a preamp for an improved perception.
Best regards
Stammheim
to be honest I'm not sure what to answer regarding your first question, beside the feedback from users and customers in this thread. There are so many devices / DAC's in different setups, that I can't give a generally valid answer, what exactly a HPULN is able to "change".
Watch out: Following is my personal experience, if you'd force me to give an answer on your risk. One else can have an own opinion
If the reader doesn't accept other opinions, please stop reading here (and work on your "bias").
As I personally use the HPULN's in several own applications to power DAC's, preamps or even amps, I can tell that my first impression always is: silence.
Well, no, of course there is music
But in a silent-cleaner way. As loud, as it was before of course. Just more focussed on the track that I wanna listen to.
I never gave a personal explenation here. Music is subjective and I don't want people to get briefed, as from my experience there always were test-auditors that heared something else improved / changed, then the others did.
Regarding your second question:
My first thought was: Wow, 250VA for a circuit that needs few hundreds mA only.
My second was: Were that exactly the same transformers with different power rate only or were there other aspects, that could give you an improved perception using that oversized transformer?
What I also thought about is, that most of commercial AVR's have a power rate twice of your preamp. But for supplying up to 11 amplifiers. That's also not a cut in your direction.
But hey, honestly:
We hear differences between several capacitors (that is NOT a cut on the previous topic!!!), no matter if they are in a signal path or in a power supply. Or differences between power or speaker cables. So why not using the 250VA transformer for a preamp for an improved perception.
Best regards
Stammheim
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