Mains voltage?
"I hate to be the party pooper but learning on the primary voltage is not a wise idea.
Before anyone plays with mains voltage they should have a TOROUGH understanding of electricity and electronics.
I fully encourage the learning and experimenting but not at the risk of personal harm."
rabstg
Sorry I don't understand your concern at this point. The mains connections have already been done and the discussion has all been about the secondary side of the transformers. I know we probably should have asked what protection he had implemented but this would have been off topic to his immediate problem.
No one advocates direct off line voltage usage that I have seen. What I have seen is the continued stressing of good safety practices in all ways.
ssanmor
Thanks for your response but I did solve my drawing problem. I do a free hand, scan it and then turn it over to my grandson to do his photoshop magic on. This is the really simple solution for me.
It would be real nice if there were a simple CAD type drawing program that had a good library of symbols to use. Of course this program would have to be able to output in the various formats and with selectable resolution. I don’t know of anything like this, do you?
Roger
"I hate to be the party pooper but learning on the primary voltage is not a wise idea.
Before anyone plays with mains voltage they should have a TOROUGH understanding of electricity and electronics.
I fully encourage the learning and experimenting but not at the risk of personal harm."
rabstg
Sorry I don't understand your concern at this point. The mains connections have already been done and the discussion has all been about the secondary side of the transformers. I know we probably should have asked what protection he had implemented but this would have been off topic to his immediate problem.
No one advocates direct off line voltage usage that I have seen. What I have seen is the continued stressing of good safety practices in all ways.
ssanmor
Thanks for your response but I did solve my drawing problem. I do a free hand, scan it and then turn it over to my grandson to do his photoshop magic on. This is the really simple solution for me.
It would be real nice if there were a simple CAD type drawing program that had a good library of symbols to use. Of course this program would have to be able to output in the various formats and with selectable resolution. I don’t know of anything like this, do you?
Roger
We now also offer the Hypex modules. These are delivered as is (the modules) and as a complete kit including the power supply and the cabinet. Have a look at this picture http://www.hawkaudio.nl/amppic/kast-D-exploded-v.jpg for a two channel amp.
Also look at http://www.hawkaudio.nl
Also look at http://www.hawkaudio.nl
Hello everybody!
I've just finished building my first two UCD 400 monoblocks, and I have a few questions on my mind:
Why does one of the UCD Monoblocks get consistently hotter than the other? The hotter Monoblock seems to be always warm to the toutch,a nd I can feel this on both the module alum T as well as on the aluminium chassis it is attached. The other module, mounted exactly the same way, some times even feel cold, and I am sure both modules are working...
What should be the best sounding capacitor bank I could use? Right now I am using a couple of United Chemicon and Samwa 6800uF capacitors(4x6800 per UCD400), as well as one 100uF eletrolytic, a 470nF polypropilene and a snubber circuit(1ohm + 220nF) per rail.
I am wondering what would be, on your experience, the best main capacitors(Fische Audio, BC 154, BHC, Sikorel, etc...) and what should be the best topology for the other filtering components. I've remember reading somewhere that the extra small capacitors may not work very well with the UCD module, but that is in disagreement with all I've read about PSUs for audio...
Thanks,
Allan
I've just finished building my first two UCD 400 monoblocks, and I have a few questions on my mind:
Why does one of the UCD Monoblocks get consistently hotter than the other? The hotter Monoblock seems to be always warm to the toutch,a nd I can feel this on both the module alum T as well as on the aluminium chassis it is attached. The other module, mounted exactly the same way, some times even feel cold, and I am sure both modules are working...
What should be the best sounding capacitor bank I could use? Right now I am using a couple of United Chemicon and Samwa 6800uF capacitors(4x6800 per UCD400), as well as one 100uF eletrolytic, a 470nF polypropilene and a snubber circuit(1ohm + 220nF) per rail.
I am wondering what would be, on your experience, the best main capacitors(Fische Audio, BC 154, BHC, Sikorel, etc...) and what should be the best topology for the other filtering components. I've remember reading somewhere that the extra small capacitors may not work very well with the UCD module, but that is in disagreement with all I've read about PSUs for audio...
Thanks,
Allan
Any chance you could stick an ammeter in the positive rail (=between the supply and the UcD) and report the idle currents (no loudspeaker attached).ninjanki said:
The UcD's have local decoupling (the 470uF/100V caps). Adding extra small caps is only done in amplifiers that have no local decoupling e.g. class AB amps.ninjanki said:
I prefer to use as few as possible different capacitor types in parallel, because usually the sound is not a mix of the best sonic characteristics of each, but a mix of the worst ones. This is why, if it's not necessary, it's best not to.
Bruno,
About the Amperimeter, I have one, but I am not used to it(use mostly for voltage and resistance measurements...), so I am not sure about how to read given the scale(12A - digital display).
Anyway, it reads 0.05 on the monoblock which seems to remain cold, while it reads 0.07 on the one that is always warm. Is that enough info?
Allan
About the Amperimeter, I have one, but I am not used to it(use mostly for voltage and resistance measurements...), so I am not sure about how to read given the scale(12A - digital display).
Anyway, it reads 0.05 on the monoblock which seems to remain cold, while it reads 0.07 on the one that is always warm. Is that enough info?
Allan
Jan-peter,
I believe I have a Snubber circuit on my capacitor bank too. If there is one on the UCD module, my snubber is useless... I am not thinking, right now, about touching anything on the UCD module... If one day I decide to do so, it will be to replace some caps with Black gates, but not at this point...
Allan
I believe I have a Snubber circuit on my capacitor bank too. If there is one on the UCD module, my snubber is useless... I am not thinking, right now, about touching anything on the UCD module... If one day I decide to do so, it will be to replace some caps with Black gates, but not at this point...
Allan
Ninjanki,
This is normal, we adjust the idle current by hand of every UcD400 module for the best THD performance on the Audio Precision. Because of some component tolerance there is difference in the idle current. But the performance of both modules is the same. In a way we have now written a PC program were the AP measures automatically all importend specs.......
If you put the both modules on a small heatsink you will have a temperature difference of a few degrees C between each module. This is hardly avoidable......
We prefer to have the THD performance the same, not the temperature........
Jan-Peter
This is normal, we adjust the idle current by hand of every UcD400 module for the best THD performance on the Audio Precision. Because of some component tolerance there is difference in the idle current. But the performance of both modules is the same. In a way we have now written a PC program were the AP measures automatically all importend specs.......
If you put the both modules on a small heatsink you will have a temperature difference of a few degrees C between each module. This is hardly avoidable......
We prefer to have the THD performance the same, not the temperature........
Jan-Peter
UcD 400 AD input circuit
Jan-Peter
I have a pair of the 400AD's and am doing some tweaking. This includes some Auricap 2UF off board input caps. This should give close enough to DC performance with out the safety hit you get with DC coupling. My question is how to handle the -sig and ground. I am using single ended input with the -sig and ground directly connected to the input jack -. Would there be any advantage to also coupling the -sig input through a cap leaving the ground a direct connection?
Is there any chance of getting a drawing of the AD version input circuit along with the regulator? This would be a big help to us tweakers.
Thanks,
Roger
Jan-Peter
I have a pair of the 400AD's and am doing some tweaking. This includes some Auricap 2UF off board input caps. This should give close enough to DC performance with out the safety hit you get with DC coupling. My question is how to handle the -sig and ground. I am using single ended input with the -sig and ground directly connected to the input jack -. Would there be any advantage to also coupling the -sig input through a cap leaving the ground a direct connection?
Is there any chance of getting a drawing of the AD version input circuit along with the regulator? This would be a big help to us tweakers.
Thanks,
Roger
Re: UcD 400 AD input circuit
If you extend your connection scheme to the preamp jack (using shielded twisted pair cable and XLR connectors, so that GND and in- are joined at the preamp), it certainly makes sense to have a cap on both lines. If you prefer to stick to using an RCA chassis connector, I wouldn't bother using 2 caps.sx881663 said:
Hello,
Big thanks for all the informations,
I never made DIY amp but already made my speakers, and for the 1st try I want to make a stereo amp that will in the near futur be use for 1 or 2 Sub.
If i can,I'd like to use a "old" DIY amp made by a friend and just replace the power supply and the UCD.
I open it and i can see 2 Vellman amp, 2x 2 capacitor Philips 63V 15.000, 2 MB101 and a ILP 61012 (2X12V 9,38A 225W).
So it will be very easy for me if I juste have to change the part not valid for the UCD.
Is it possible to use UCD400 amp with 63V capacitor or I must use UCD180 ?
Thanks
Dimitri
Big thanks for all the informations,
I never made DIY amp but already made my speakers, and for the 1st try I want to make a stereo amp that will in the near futur be use for 1 or 2 Sub.
If i can,I'd like to use a "old" DIY amp made by a friend and just replace the power supply and the UCD.
I open it and i can see 2 Vellman amp, 2x 2 capacitor Philips 63V 15.000, 2 MB101 and a ILP 61012 (2X12V 9,38A 225W).
So it will be very easy for me if I juste have to change the part not valid for the UCD.
Is it possible to use UCD400 amp with 63V capacitor or I must use UCD180 ?
Thanks
Dimitri
Got a Q for the group here. I think I @*&%$'d one of my UcD400 modules. 
I was awaiting the arrival of a new preamp but wanted to test out my UcD400 based amp so I borrowed a friend's preamp (Blue Circle BC3 Galatea). Not being familiar enough with the preamp, I didn't wait long enough before turning on the UcD. I heard a little motor boating. One of the channels was then not making any music.
I had been running the UcD amp the day before and everything was golden but when I went to play it the second day I got nothing from the second module. I checked my voltages on the PSU rails and everything was good. Checked all the connections, good. When I flip the /on switch the LED comes on but no signal in that channel of the speaker.
Through a series of tests with other amps and speakers I determined it definitely is the amp and is the one channel. My question is how do I go about testing what went wrong? I am still fairly newb, so I am not quite sure how to test the switching transistors to make sure they are good. What else should and how should I test?
saddened,
Josh
I was awaiting the arrival of a new preamp but wanted to test out my UcD400 based amp so I borrowed a friend's preamp (Blue Circle BC3 Galatea). Not being familiar enough with the preamp, I didn't wait long enough before turning on the UcD. I heard a little motor boating. One of the channels was then not making any music.
I had been running the UcD amp the day before and everything was golden but when I went to play it the second day I got nothing from the second module. I checked my voltages on the PSU rails and everything was good. Checked all the connections, good. When I flip the /on switch the LED comes on but no signal in that channel of the speaker.
Through a series of tests with other amps and speakers I determined it definitely is the amp and is the one channel. My question is how do I go about testing what went wrong? I am still fairly newb, so I am not quite sure how to test the switching transistors to make sure they are good. What else should and how should I test?
saddened,
Josh
Gilbert of Blue Circle said that there is no chance that DC was outputted from the preamp as it has caps on the output. Still my module isn't working and the voltages from the PSU measure correctly and all my connections are good. Don't know what it could be. Is there anything I can test to try and figure this out?
Blown amp module
Tube preamps generally are cap coupled and shouldn't put out any DC unless the caps are defective. However, on turn on there will be a very large turn on DC surge unless the preamp has a built in mute relay to short the output till the caps are charged. This surge can reach 100 volts or more going into a high input impeadance circuit like the UCD has. This surge can kill input circuits even if the amp is turned off unless amp input limit diodes are installed. As far as I know the UCD has none. There is a slight chance that only the input chip is blown. This would be a good question for Bruno.
Roger
JoshKJoshK said:
Tube preamps generally are cap coupled and shouldn't put out any DC unless the caps are defective. However, on turn on there will be a very large turn on DC surge unless the preamp has a built in mute relay to short the output till the caps are charged. This surge can reach 100 volts or more going into a high input impeadance circuit like the UCD has. This surge can kill input circuits even if the amp is turned off unless amp input limit diodes are installed. As far as I know the UCD has none. There is a slight chance that only the input chip is blown. This would be a good question for Bruno.
Roger