That means around 10W, right?
I suppose that UcD400 is not safe without a heatsink even with no signal, it must get quite hot. Can you, users, confirm this?
I suppose that UcD400 is not safe without a heatsink even with no signal, it must get quite hot. Can you, users, confirm this?
True,
Without signal and turned on (led on) it gets quite hot when not attached to a heatsink.
It converts quite a bit of energy when off also. My 22.000uF caps on each rail are exhausted in about a minute to 90 secs time, even when the "on" switch is in position off. (blue led off)
Without signal and turned on (led on) it gets quite hot when not attached to a heatsink.
It converts quite a bit of energy when off also. My 22.000uF caps on each rail are exhausted in about a minute to 90 secs time, even when the "on" switch is in position off. (blue led off)
Pierre said:
No, you really need a heatsink or mount it on an aluminum plate like the bottom or sides of an enclosure. In fact, I think the more heatsinking the better (although overdoing it makes no sense) as the lower temperature of the switching mosfets keeps the on resistance of the fets lower and thus the efficiency higher and likely sound quality higher (even less distortion).
Best regards
Gertjan
A stereo amp uses 22VA at idle and at maximum outpup, well in my case 150W per channel, looses 33W in total. That's also including toroid losses. But in a small case you need a cooling bloc for the UCD400. The UCD180 needs very little.
OK, another question more. This relates to both ZAP Pulse and Ucd modules:
When you have problems like "whistles" due to close proximity of two or more modules, how is that solved?
I have experienced some similar problem with two of my "clocked" modules: when they are near, there can be a very slight and high-pitched tone on the speaker. As soon as you turn one of then off, it disappears in the other.
I recall having read something about putting a cap between both outputs, but don't know if that advice was from ZAP pulse or Hypex. Anyway, I would like to know if that "synchronises" the modules at the same freq or what.
When you have problems like "whistles" due to close proximity of two or more modules, how is that solved?
I have experienced some similar problem with two of my "clocked" modules: when they are near, there can be a very slight and high-pitched tone on the speaker. As soon as you turn one of then off, it disappears in the other.
I recall having read something about putting a cap between both outputs, but don't know if that advice was from ZAP pulse or Hypex. Anyway, I would like to know if that "synchronises" the modules at the same freq or what.
I had that with a couple of Zap 2.2SE modules. I solved it by dismantling the amp and leaving the bits on the workbench...
However, my other Zap amp is OK and in that one I put the modules seperate from each other on opposite sides of the case. It also sounds a lot better than the previous Zap (better powersupply)
I am not sure the UCD has the problem at all (unless you are telling me that it does for you?)
If it's a Zap issue better take it straight to LCAudio...
However, my other Zap amp is OK and in that one I put the modules seperate from each other on opposite sides of the case. It also sounds a lot better than the previous Zap (better powersupply)
I am not sure the UCD has the problem at all (unless you are telling me that it does for you?)
If it's a Zap issue better take it straight to LCAudio...
ucd 180 ucd 400
Hello!
I want to build an amplifier with ucd 180 and ucd 400 modules and I need to solve some doubts:
That design of power supply must follow?
Supports < 4 ohm?
what toroidal I must buy?
Thank´s
Hello!
I want to build an amplifier with ucd 180 and ucd 400 modules and I need to solve some doubts:
That design of power supply must follow?
Supports < 4 ohm?
what toroidal I must buy?
Thank´s
Pierre said:
I assume you had the whistles with the ZAP? I have tried ZAPs and I had whistles. Although it seems to be possible to make the ZAPs whistle free. With UcD I have no whistles, it seems that UcD has better RFI/EMI characteristics making them less critical to handle, so I would be really surprised if you would get this with UcD.
Heatsink: The 400's need a heatsink, even in idle. Simply fastening them to the cabinet is usually sufficient. To industrial customers I generally suggest around 4.5K/W worth of heatsinking, that's enough for even the most stringent official tests.
Whistles: The EMI filtering on all ends of the modules is such that it's actually quite hard to get whistling on UcD modules. You'd have to do something seriously wrong (like flying bare input signal leads across the bottom of the adjoining module) before you got any whistles. So far no comments from users who pulled that off 😉
PS: I'm off for a short holiday in Slovakia for a week and a half to laze at a holiday camp dating from the communist era. There's no internet access there, which probably subconsciously contributed to my choice of stay.
Whistles: The EMI filtering on all ends of the modules is such that it's actually quite hard to get whistling on UcD modules. You'd have to do something seriously wrong (like flying bare input signal leads across the bottom of the adjoining module) before you got any whistles. So far no comments from users who pulled that off 😉
PS: I'm off for a short holiday in Slovakia for a week and a half to laze at a holiday camp dating from the communist era. There's no internet access there, which probably subconsciously contributed to my choice of stay.
Bruno Putzeys said:
Have a good holiday. I'll be going to Holland for a bit more than 2 weeks from this Thursday.
Best regards
Gertjan
Darn, my new stereo UCD 400 *nearly* works. Can anyone help figure out what I have done wrong...
Basically the right channel amp plays something for a second or two when you turn it on and then presumably goes into protection. Curiously when I turn off the power, after a couple of seconds (as the caps drain) the amp suddenly comes out of protection and you can hear stuff again (presumably at risk to the speakers...)
The left channel plays fine. It's a dual mono supply and everything is duplicated after the softstart.
How do I debug this and figure out what is causing it to go into protection?
Debugging notes:
- I shorted out the input capacitors... But the left channel works ok, and swapping around the source inputs to the amp doesn't make a different. Also the UCD400 mk1 modules play fine with this source component (no DC measured on the source)
- I wired some 10nF MKT caps from the speaker outputs on the board to ground. Possibly something is shorted here, but a quick test with a meter shows something like 10K (and rising) resistance from hot speaker output to ground, and zero resistance from speaker ground to chassis ground.
- There doesn't appear to be any DC on the speaker output when I turn on the amp with a speaker as a load.
- Powersupply voltage is measured at 60v on both rails. Haven't checked that this is reaching the modules, but the only thing in the way could be a dead fuse (can't get to it to test). I don't think a missing power rail would cause the above symptoms though?
Can anyone suggest some tests to narrow this down?
Thanks
Basically the right channel amp plays something for a second or two when you turn it on and then presumably goes into protection. Curiously when I turn off the power, after a couple of seconds (as the caps drain) the amp suddenly comes out of protection and you can hear stuff again (presumably at risk to the speakers...)
The left channel plays fine. It's a dual mono supply and everything is duplicated after the softstart.
How do I debug this and figure out what is causing it to go into protection?
Debugging notes:
- I shorted out the input capacitors... But the left channel works ok, and swapping around the source inputs to the amp doesn't make a different. Also the UCD400 mk1 modules play fine with this source component (no DC measured on the source)
- I wired some 10nF MKT caps from the speaker outputs on the board to ground. Possibly something is shorted here, but a quick test with a meter shows something like 10K (and rising) resistance from hot speaker output to ground, and zero resistance from speaker ground to chassis ground.
- There doesn't appear to be any DC on the speaker output when I turn on the amp with a speaker as a load.
- Powersupply voltage is measured at 60v on both rails. Haven't checked that this is reaching the modules, but the only thing in the way could be a dead fuse (can't get to it to test). I don't think a missing power rail would cause the above symptoms though?
Can anyone suggest some tests to narrow this down?
Thanks
ewildgoose said:
Have you checked the voltage on the shut down input pin? Have you physically swapped the modules? Did you do any further mods to them?
Roger
ewildgoose said:
Check if the + cable is not grounded by error (bad cable with contact to chassis).
Stef...
I'm not sure what you mean by "voltage on the shut down input pin"?
I have done some further testing since Jan-Peter suggested it might be pumping:
Voltage on powerup to the module seems to rise smoothly and slowly up to 60v, but in the case of this test there was no momentary sound from the modules. Voltage on the other rail was then tested and looked good at -60v.
I then removed the power from the amp and as the voltage dropped to around 40v the module started playing...
I can't see any evidence with a meter that there is any accidental grounding of the speaker +ve output. Using a meter shows at least 10K of resistance. (There is a path through the capacitor of course)
I have put up two photos here:
http://www.wildgooses.com/temp/IMG_6753.JPG
http://www.wildgooses.com/temp/IMG_6754.JPG
The non-working module is the right hand one, ie the one without the input shorting plug.
I have tested the input source and it works fine on the left hand module, but the right hand module just shuts down as described with either left of right channel input.
I haven't tested that the "on" wire is properly grounded, but if not then it shouldn't play on shutdown should it?
It's hard to figure out what the fault condition should be. I guess the first step is going to have to be to remove the shorts on the input caps C23/24 and see if that helps. It's a slightly complicated process that I don't have time to do until at least tomorrow though.
Does anyone have any suggestions before I power it down and dismantle?
Thanks
Ed W
I have done some further testing since Jan-Peter suggested it might be pumping:
Voltage on powerup to the module seems to rise smoothly and slowly up to 60v, but in the case of this test there was no momentary sound from the modules. Voltage on the other rail was then tested and looked good at -60v.
I then removed the power from the amp and as the voltage dropped to around 40v the module started playing...
I can't see any evidence with a meter that there is any accidental grounding of the speaker +ve output. Using a meter shows at least 10K of resistance. (There is a path through the capacitor of course)
I have put up two photos here:
http://www.wildgooses.com/temp/IMG_6753.JPG
http://www.wildgooses.com/temp/IMG_6754.JPG
The non-working module is the right hand one, ie the one without the input shorting plug.
I have tested the input source and it works fine on the left hand module, but the right hand module just shuts down as described with either left of right channel input.
I haven't tested that the "on" wire is properly grounded, but if not then it shouldn't play on shutdown should it?
It's hard to figure out what the fault condition should be. I guess the first step is going to have to be to remove the shorts on the input caps C23/24 and see if that helps. It's a slightly complicated process that I don't have time to do until at least tomorrow though.
Does anyone have any suggestions before I power it down and dismantle?
Thanks
Ed W
right channel problem
Ed,
Sounds like the “on” pin is open. Capacitive effects associated with this pin could explain what you are experiencing.
Roger
Ed,
Sounds like the “on” pin is open. Capacitive effects associated with this pin could explain what you are experiencing.
Roger
Maybe check out the overvoltage protection circuit bias etc..
Does it act like over voltage protection has kicked in? It doesn't seem like it's pumping but if it's tripping early I could see it causing your symptoms.
Does it act like over voltage protection has kicked in? It doesn't seem like it's pumping but if it's tripping early I could see it causing your symptoms.
I checked the grounding of the "on" pin and it looks good. I will retest tomorrow though
I wonder if the overvoltage protection could be tripping early though...
Jan-Peter has sent me some debug steps offlist and I will work through these first and see if I can figure out what I have done wrong.
Thanks all
Ed
I wonder if the overvoltage protection could be tripping early though...
Jan-Peter has sent me some debug steps offlist and I will work through these first and see if I can figure out what I have done wrong.
Thanks all
Ed
Ewildgoose, I hope your making progress with your Amp, I am about to start putting mine together. Do you have any pictures of yours?
What softstart are you using? I was hoping to get away without one for mine but with a 500VA transformer I think I may have to put one in.
Regards
What softstart are you using? I was hoping to get away without one for mine but with a 500VA transformer I think I may have to put one in.
Regards