Not yet, but I do have the modules! I'm waiting on RS for a case that's currently on back-order.
I'm also procrastinating over the PSU, whether one big transformer and reservoir (shared between two modules), one transformer + 2 rec's / reservoirs, or just to go the whole hog (given custom transformers with twin secondaries aren't off the shelf items) and fit two independant PSU's, like two monoblocks in a single case.
Decisions, decisions...
Andy.
ALW said:
I've given mine dual transformers etc, I'm still faffing about with the PSU's and input op-amp stage
Anyway don't forget to let us know how you get on😉
Leo
Pasi P said:
Pasi, did you try it like this before?
http://www.diyaudio.com/forums/showthread.php?s=&threadid=65223&highlight=
I added 2 100nf caps. on the input cinch parts for cap.coupling of chassis to the ground of the input wires.
BTW I never had humm anymore with the mod. and crosstalk is superb.
Hi,
Andy, I agree about the double insulation.
They never gave much of a reason for not using star grounding, as it's all arguable, best reason given was whoever invented it is some sort of an idiot.
That's Ok to say too, I think, if backed up thoroughly with an alternative. The alternative provided by way of that schematic is however far from thorough, in fact it hardly scratches the surface.
The problem lies in that most will count on it as a step by step how-to guide. Then comes the hum, then people resort to bandaides like modifying their cables, or far worse, settle for the first less than optimal method they find which produces no hiss or hum, of which there are many, and are then left with a very muddied sound, which they aren't even likely to realize, because they'll never know how good it can really be.
Maybe that's just excellent information for a monoblock. Throw two amps in there and what happens? How about four? How about bi-phase?
Our"manual" isn't answering so much now is it?
Pasi, connect your inputs the way you had them before, I would assume all commons tied to a single point on the chassis, with all signal grounds of the modules connected to the same point. Oh look, a star. I did the same with my shields in balanced mode. Works great. I think Bill did too.
Float your supply ground from the chassis so you don't form a loop through the module (the real reason to not ground the PSU to chassis), and also pollute the signal ground.
If you want to wire any amps in reverse phase to the others, You're just going to have to isolate them from each other, or disgusting hum will result. Most easily done by floating the signal ground.
You've got it easy since you have no earth grounds to deal with and that immediatly eliminates a few possible loops.
Normally the chassis gets connected to earth.
Regards,
Chris
Andy, I agree about the double insulation.
They never gave much of a reason for not using star grounding, as it's all arguable, best reason given was whoever invented it is some sort of an idiot.
That's Ok to say too, I think, if backed up thoroughly with an alternative. The alternative provided by way of that schematic is however far from thorough, in fact it hardly scratches the surface.
The problem lies in that most will count on it as a step by step how-to guide. Then comes the hum, then people resort to bandaides like modifying their cables, or far worse, settle for the first less than optimal method they find which produces no hiss or hum, of which there are many, and are then left with a very muddied sound, which they aren't even likely to realize, because they'll never know how good it can really be.
Maybe that's just excellent information for a monoblock. Throw two amps in there and what happens? How about four? How about bi-phase?
Our"manual" isn't answering so much now is it?
Pasi, connect your inputs the way you had them before, I would assume all commons tied to a single point on the chassis, with all signal grounds of the modules connected to the same point. Oh look, a star. I did the same with my shields in balanced mode. Works great. I think Bill did too.
Float your supply ground from the chassis so you don't form a loop through the module (the real reason to not ground the PSU to chassis), and also pollute the signal ground.
If you want to wire any amps in reverse phase to the others, You're just going to have to isolate them from each other, or disgusting hum will result. Most easily done by floating the signal ground.
You've got it easy since you have no earth grounds to deal with and that immediatly eliminates a few possible loops.
Normally the chassis gets connected to earth.
Regards,
Chris
As with all 'systems' it has to be considered thoroughly as just that, as a system.
To that end you can't build a power amp, DAC, preamp or anything without considering it's impact on the rest of the system and how it connects, the potential earthing problems, current flows, EMI / EMC effects etc.
If I built from scratch a new system, it would be fully balanced and properly done, i.e. the sheilds and cases would be just that, and not carry any audio signals or be connected to the signal path. Unfortunately that's not where I am at present 😉
My system is single ended, all cases are earthed, but there's only a single connection between mains earth and the signal path (in a source component, as it happens).
The whole system follows a star-earth principle and the Hypex modules will have to be integrated into that, without degrading other items, which will be interesting to achieve, but to anyone experiencing hum, draw out the interconnections between your system components and the signal earth to mains earth connections and look for loops, these need to be eliminated to stand a chance of operating optimally in a primarily single ended environment.
Fundamentally though it must be safe, I couldn't possibly condone following the Hypex recommendation for single ended wiring though, unless you really know how to make a double insulated item that's safe.
If you have to question what it involves, don't do it, or research it thoroughly!
Dead customers aren't good for repeat orders 😉
Andy.
To that end you can't build a power amp, DAC, preamp or anything without considering it's impact on the rest of the system and how it connects, the potential earthing problems, current flows, EMI / EMC effects etc.
If I built from scratch a new system, it would be fully balanced and properly done, i.e. the sheilds and cases would be just that, and not carry any audio signals or be connected to the signal path. Unfortunately that's not where I am at present 😉
My system is single ended, all cases are earthed, but there's only a single connection between mains earth and the signal path (in a source component, as it happens).
The whole system follows a star-earth principle and the Hypex modules will have to be integrated into that, without degrading other items, which will be interesting to achieve, but to anyone experiencing hum, draw out the interconnections between your system components and the signal earth to mains earth connections and look for loops, these need to be eliminated to stand a chance of operating optimally in a primarily single ended environment.
Fundamentally though it must be safe, I couldn't possibly condone following the Hypex recommendation for single ended wiring though, unless you really know how to make a double insulated item that's safe.
If you have to question what it involves, don't do it, or research it thoroughly!
Dead customers aren't good for repeat orders 😉
Andy.
Thank you all for good tips and information!
Unfortunately it seems that i have very busy at work some weeks but i will tell results / ask more when i have time to open UCD:s bonnet again..
Unfortunately it seems that i have very busy at work some weeks but i will tell results / ask more when i have time to open UCD:s bonnet again..
Hi Andy 😀
We hope you like them, but also we expect that maybe you will be the first to try super-regulated independent opamp supplies 😉
For now, I am ordering some small R-core Tx's for the future...
BTW, diyclub.biz has 400VA, R-core Tx's.
I suppose I'm lucky 😎 I run balanced signals from M-audio superDAC to Stevens&Billington's TVC to UCD's, floating signal grounds at TVC, system dead quiet at idle
Best of lucks
Mauricio.
We hope you like them, but also we expect that maybe you will be the first to try super-regulated independent opamp supplies 😉
For now, I am ordering some small R-core Tx's for the future...
BTW, diyclub.biz has 400VA, R-core Tx's.
I suppose I'm lucky 😎 I run balanced signals from M-audio superDAC to Stevens&Billington's TVC to UCD's, floating signal grounds at TVC, system dead quiet at idle
Best of lucks
Mauricio.
I am sorry, i have given wrong information 
When inputs are shorted, UCD:s are dead quiet (when i first quickly test it, i suppose one mains cable was very near RCA inputs and it causes hum). So it seems that this new grounding of UCD, recommended by Hypex is OK. Also sound is good 🙂
But when amp is connected to preamp (DIY dact stepped attenuator+Orion filter), there is bit more hum than before. So i think i have to investigate grounding for my preamp, not UCD.
When inputs are shorted, UCD:s are dead quiet (when i first quickly test it, i suppose one mains cable was very near RCA inputs and it causes hum). So it seems that this new grounding of UCD, recommended by Hypex is OK. Also sound is good 🙂
But when amp is connected to preamp (DIY dact stepped attenuator+Orion filter), there is bit more hum than before. So i think i have to investigate grounding for my preamp, not UCD.
Hi Pasi,
You also said you had no grounds in that room at all? If that's the case I can't see your preamp being an issue?
What of this filter of yours?
Regards,
Chris
You also said you had no grounds in that room at all? If that's the case I can't see your preamp being an issue?
What of this filter of yours?
Regards,
Chris
Chris,
I have Orion ASP filter and it causes clearly hf noise. But in old UCD grounding, hum is clearly smaller than now. OK, hum is not loud, in silent room i can hear it about 30cm (1ft) from speaker.
(I have 6-ch Dact stepped attenuator after Orion filter to decrease noise and it works very well in that aspect. )
Yes, i do not have mains safety earthing.
I have Orion ASP filter and it causes clearly hf noise. But in old UCD grounding, hum is clearly smaller than now. OK, hum is not loud, in silent room i can hear it about 30cm (1ft) from speaker.
(I have 6-ch Dact stepped attenuator after Orion filter to decrease noise and it works very well in that aspect. )
Yes, i do not have mains safety earthing.
Hi Pasi,
What is the main difference in your wiring from before? Did you just seperate the inputs in the chassis + float the supply from it?
You'll reduce the hum by connecting the inputs in a star fashion on the chassis I think, probably like you had before.
Alternatively, wait a few weeks for the new wiring paper out by Hypex, I'm sure we'll all learn something from it.
Regards,
Chris
What is the main difference in your wiring from before? Did you just seperate the inputs in the chassis + float the supply from it?
You'll reduce the hum by connecting the inputs in a star fashion on the chassis I think, probably like you had before.
Alternatively, wait a few weeks for the new wiring paper out by Hypex, I'm sure we'll all learn something from it.
Regards,
Chris
Pasi,
You can use a 10 ohm resistor between signal ground (at the RCA in) and the chassis.
That should eliminate any ground loop problem you might have.
With all this ground discussion, I moved my ground connection to chassis from the power supply to the line input. In both cases I use a 10 ohm resistor. I have/had no problem with noise. But I have a slight impression that the ground connected to chassis at the input sounds better, it's hard to tell though. It's a minor sonic difference, if any. My chassis is earth grounded.
On a side note, I installed the BG's in my modules and, although they're far from full break-in they appear to have a seductive mid range. I imagine these are just pre break in colorations. The Panasonic FC sounded a bit like that too in the beginning...
You can use a 10 ohm resistor between signal ground (at the RCA in) and the chassis.
That should eliminate any ground loop problem you might have.
With all this ground discussion, I moved my ground connection to chassis from the power supply to the line input. In both cases I use a 10 ohm resistor. I have/had no problem with noise. But I have a slight impression that the ground connected to chassis at the input sounds better, it's hard to tell though. It's a minor sonic difference, if any. My chassis is earth grounded.
On a side note, I installed the BG's in my modules and, although they're far from full break-in they appear to have a seductive mid range. I imagine these are just pre break in colorations. The Panasonic FC sounded a bit like that too in the beginning...
Chris,
My first wiring was:
RCA inputs grounds isolated from enclosure, power supply 0V star grounded to chassis.
My current wiring is:
RCA inputs grounded from enclosure, power supply 0V floating.
No any other changes.
I am waiting for Hypex new papers.. Just playing music for a while 😎
My first wiring was:
RCA inputs grounds isolated from enclosure, power supply 0V star grounded to chassis.
My current wiring is:
RCA inputs grounded from enclosure, power supply 0V floating.
No any other changes.
I am waiting for Hypex new papers.. Just playing music for a while 😎
Julien_M
"On a side note, I installed the BG's in my modules and, although they're far from full break-in they appear to have a seductive mid range. I imagine these are just pre break in colorations. The Panasonic FC sounded a bit like that too in the beginning..."
Did you install BG's for the following:
1. Two main supply caps - 220uf 100V (std)
2. Boot Strap - 220uf 16V (std)
3. Two 22uf 50V (pk) filter caps
Would like to know if you had any problems fitting them on the board as far as overall diameter & lead thickness?
Thanks
"On a side note, I installed the BG's in my modules and, although they're far from full break-in they appear to have a seductive mid range. I imagine these are just pre break in colorations. The Panasonic FC sounded a bit like that too in the beginning..."
Did you install BG's for the following:
1. Two main supply caps - 220uf 100V (std)
2. Boot Strap - 220uf 16V (std)
3. Two 22uf 50V (pk) filter caps
Would like to know if you had any problems fitting them on the board as far as overall diameter & lead thickness?
Thanks
Stevenacnj said:
I installed all but the boot strap cap. I have a Panasonic FM in there. I find the FM's more neutral and transparent than the FC's. I don't plan in changing the bootstrap cap now.
All caps I installed fit perfectly on the PCB. They're all flush with the board.
The BlackGates are now starting to sound more neutral with more mid range definition. In my opinion, as they are now, they're a definite improvement over the Panasonics. The major improvement is in timbre. I find the midrange and highs to sound more natural. The sound stage presence had improve as well.
My next steps in the UcD amp is to change some bypass caps from Panasonic Polypropylene to Sonicap Gen II, and later change the output LC cap from a BC Component Polypropylene to a 0.47uF/200V Sonicap Gen II.
Finally, I intend to change the 4 bridges in my dual mono power supply with FRED bridges.
I definitely plan to try some things out along that line, an additional reason for the PSU procrastination, since the low-level stuff might favour a seperate transformer. Initially though I'm trying them as-is, just to get to know them a little first 😉
I'm strongly veering towards one big TX and a smaller one for the front end.
Andy.
Andy:
That's the way to go, IMHO
If someone wants to get R-core Tx for the front end, I found a place: diyclub.biz
US$15 for one 50VA Tx. From HongKong, I'm affraid.
Off topic:
Next week I will populate my M-audio superDAC with more ALWSR's 😎
("BTS" mod, He-he 😀 I won't tell my lady)
Good luck!
M
That's the way to go, IMHO
If someone wants to get R-core Tx for the front end, I found a place: diyclub.biz
US$15 for one 50VA Tx. From HongKong, I'm affraid.
Off topic:
Next week I will populate my M-audio superDAC with more ALWSR's 😎
("BTS" mod, He-he 😀 I won't tell my lady)
Good luck!
M
Julien_M
"change the output LC cap from a BC Component Polypropylene to a 0.47uF/200V Sonicap Gen II."
I have five UCD 400AD's that I am going to mod. Had them for a while now, just havent gotten to it.
But I purchased the .47uf 200v Sonicap GenII for the output cap. Smallest sized quality cap that can be found.
BTW, if you get them, according to Jeff G. @ Sonic Craft, the shorter lead goes to ground.
Thanks for BG update.
"change the output LC cap from a BC Component Polypropylene to a 0.47uF/200V Sonicap Gen II."
I have five UCD 400AD's that I am going to mod. Had them for a while now, just havent gotten to it.
But I purchased the .47uf 200v Sonicap GenII for the output cap. Smallest sized quality cap that can be found.
BTW, if you get them, according to Jeff G. @ Sonic Craft, the shorter lead goes to ground.
Thanks for BG update.
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