UDC180 set up
This is the first time I put together an amplifier. I bought 2 each of transformers, power supplies and UDC180c from Hypex. All will be installed in one box. Each PS is designed to energize 2 amps. In my case, each PS will be connected to a UDC180. I wonder if half of the PS will be wasted. If so, is there any method to fully utilize the PS. I went thru the thread to look for similar topic, but I may miss it some where. I would appreciate for any comments or help. Thanks in advance.
This is the first time I put together an amplifier. I bought 2 each of transformers, power supplies and UDC180c from Hypex. All will be installed in one box. Each PS is designed to energize 2 amps. In my case, each PS will be connected to a UDC180. I wonder if half of the PS will be wasted. If so, is there any method to fully utilize the PS. I went thru the thread to look for similar topic, but I may miss it some where. I would appreciate for any comments or help. Thanks in advance.
The power section of the PS is single - the only thing that is double is the DC protection circuitry.
Sure, there are 2 sets of terminals to connect your UcD's to, but they are parallel. You don't waste any available power, in fact you'll have even more power headroom per channel.
I'll possibly (if I have the money) connect a third UcD module to the HG PS, with a switch to turn it on and off - this will become my centre channel.
I won't have DC protection for the C channel, but I've got some velleman DC protection sets lying around, better than nothing for my centre.
Sure, there are 2 sets of terminals to connect your UcD's to, but they are parallel. You don't waste any available power, in fact you'll have even more power headroom per channel.
I'll possibly (if I have the money) connect a third UcD module to the HG PS, with a switch to turn it on and off - this will become my centre channel.
I won't have DC protection for the C channel, but I've got some velleman DC protection sets lying around, better than nothing for my centre.
Hi,
Just for kicks I thought I'd post my test rig of a 180 module.
The rig and connections are exactly like I used with my homebrew amp, but the noise floor is buried, there is no hiss, no 60Hz hum, I can detect a faint hiss with the ear right next to the speaker using 15' of unbalanced /unshielded interconnect, I'm impressed with that.
Hope you like my soft start technique, it's a 500VA toroid, 10 000uF Cerafines and a really cheap bridge rectifier, rails are 47V with no load and 46 loaded.
In stock form I find the sound of the module is second to none, knowing it can only get better from here (by way of implementation etc) is really very astonishing.
I find it a little softer and silkier than expected but imagine that will change dramatically with a few mods, not that it isn't highly pleasing.
Regards,
Chris
Just for kicks I thought I'd post my test rig of a 180 module.
The rig and connections are exactly like I used with my homebrew amp, but the noise floor is buried, there is no hiss, no 60Hz hum, I can detect a faint hiss with the ear right next to the speaker using 15' of unbalanced /unshielded interconnect, I'm impressed with that.
Hope you like my soft start technique, it's a 500VA toroid, 10 000uF Cerafines and a really cheap bridge rectifier, rails are 47V with no load and 46 loaded.
In stock form I find the sound of the module is second to none, knowing it can only get better from here (by way of implementation etc) is really very astonishing.
I find it a little softer and silkier than expected but imagine that will change dramatically with a few mods, not that it isn't highly pleasing.
Regards,
Chris
Attachments
Posting
Chris,
Now I know why you haven't been posting as much lately. Do wish you had some decent test equipment you could use. Maybe someone would donate an old scope to the cause. Now that I am thinking of it I may have an old Phillips I have no use for. I’ll have to check it out.
Roger
Chris,
Now I know why you haven't been posting as much lately. Do wish you had some decent test equipment you could use. Maybe someone would donate an old scope to the cause. Now that I am thinking of it I may have an old Phillips I have no use for. I’ll have to check it out.
Roger
Bypassing opamps
Hi,
my 8 modules have arrived 🙂)
Two are already running in the test setup.
I have a question:
As I use a opamp based X-over in front of the UCD180 modules, has anyone bypassed the opamp on the UCD? I remember it was mentionend on the thread. Is it that simple as putting the balanced input signal to the amp side of the coupling caps? Is there any drawback from the 30 cm of cable before?
Thanks
Stephan
Hi,
my 8 modules have arrived 🙂)
Two are already running in the test setup.
I have a question:
As I use a opamp based X-over in front of the UCD180 modules, has anyone bypassed the opamp on the UCD? I remember it was mentionend on the thread. Is it that simple as putting the balanced input signal to the amp side of the coupling caps? Is there any drawback from the 30 cm of cable before?
Thanks
Stephan
My UcD180
Here's my story.
I needed a more powerfull amplifier for my 5.1 setup.
I decided to go for a test with the Hypex UcD180 after reading the Q&A on this web site (pheev, what a threat). I started with 2 ch. STD modules.
This test lasted about a week - then I had the verdict, I was going for the 5 channels. Meanwhile I wanted an "understatement", something cool. I found a worn out NAD 2100 and took it apart. That enclosure would give me the wanted look and WAF.
Attached's the finished amp. The one EI core supplies the FL+FR amps, the other the rest. I'm using full (dual) rectification for maximum stiffness. The FL+FR are using the AD version, the rest the STD version. I haven't implemented DC protection - I like the simplicity in the design. I decided to believe in Hypex electronics - and won't blame JP if one of my modules fails. It's what I consider as a calculated risk.
My conclusion?
It's amazing. No less. It's alive and kicking. It's playing music - and that’s all to my.
For you who are considering - go for it!
Thanks to JP for beeing there on the mail.
/AVR300
Here's my story.
I needed a more powerfull amplifier for my 5.1 setup.
I decided to go for a test with the Hypex UcD180 after reading the Q&A on this web site (pheev, what a threat). I started with 2 ch. STD modules.
This test lasted about a week - then I had the verdict, I was going for the 5 channels. Meanwhile I wanted an "understatement", something cool. I found a worn out NAD 2100 and took it apart. That enclosure would give me the wanted look and WAF.
Attached's the finished amp. The one EI core supplies the FL+FR amps, the other the rest. I'm using full (dual) rectification for maximum stiffness. The FL+FR are using the AD version, the rest the STD version. I haven't implemented DC protection - I like the simplicity in the design. I decided to believe in Hypex electronics - and won't blame JP if one of my modules fails. It's what I consider as a calculated risk.
My conclusion?
It's amazing. No less. It's alive and kicking. It's playing music - and that’s all to my.
For you who are considering - go for it!
Thanks to JP for beeing there on the mail.
/AVR300
Attachments
Re: My UcD180
It looks as if each section has two capacitors for each rail. You might want to try sticking a 0.2 ohm 20 watt (or thereabouts) resistor between the capacitor closest to the rectifier and the cap closest to the amplifiers. It's a cute trick the Pass amp people have been doing for a while, and it reduces supply ripple by quite a bit. The ripple spectrum is nicer, too.
Francois.
avr300 said:
It looks as if each section has two capacitors for each rail. You might want to try sticking a 0.2 ohm 20 watt (or thereabouts) resistor between the capacitor closest to the rectifier and the cap closest to the amplifiers. It's a cute trick the Pass amp people have been doing for a while, and it reduces supply ripple by quite a bit. The ripple spectrum is nicer, too.
Francois.
Wow, very neat!
I twisted myself the PS wires that I forgot to twist when I plit my 4ch amp in two. I would lie if I declare a big improvement.
I saw recently a pick of a new amp from Krell with notorious lack of this implementation.
I twisted myself the PS wires that I forgot to twist when I plit my 4ch amp in two. I would lie if I declare a big improvement.
I saw recently a pick of a new amp from Krell with notorious lack of this implementation.
maxlorenz said:
Twisting is usefull when you have a dense cable tree where there are more different channel wires next to each other. In a separate system, monoblocs, I also doubt there will be any sonic improvement.
Doubt there may be, however, the time to twist your PS cables is shorter than the time needed to log on to diyAudio.com and do a single post.
If a possible good tweak is this cheap,why *not* do it?
I won't be putting stones on my amp though 😀
If a possible good tweak is this cheap,why *not* do it?
I won't be putting stones on my amp though 😀
Don't twist the loudspeaker wires from the UcD module, put them next to the transformer where the wires leaves the transformer. AND you will have hum..........
So when you twist the wires, the hum is away..... 😉
Jan-Peter
So when you twist the wires, the hum is away..... 😉
Jan-Peter
I don't know why you guys would doubt twisting or say imply it's not worth doing.
It's not like the foam cups under the cable as cure for microphonics it's actually based on good engineering, we know it works because it doeswork in a big mess of high speed signal wires, and by the same method it works in that application it can benefit us here.
You have a radio frequency power converter running, possibly more than a few in close proximity, which you expect to work with the least interferance and noise as possible, yet aren't sold on twisting the wires to make the induced RFI/EMI common mode so that it stands some chance at rejecting it, both in the wires themselves and at the amplifier level. Have you really researched skin effect and such things?
Sure in a monoblock setup with shielded everything it will be much less apparent and certainly critical, but then we still have the "it cost .5 cent of wire" argument, while good shielded wire seems to be a little pricier. There's just no good reason not to call it the one and only right way and do it like that every single time, I put it right there along side star point ground systems.
My test rig has absolutely no hum with just maybe only 3 or 4 twists of the output wires, and it is a test rig so I'll let you know what happened when I untwist them. The speaker is 102 dB [ 1w / 1m ] efficiency so I would hear just about anything on them.
Regards,
Chris
It's not like the foam cups under the cable as cure for microphonics it's actually based on good engineering, we know it works because it doeswork in a big mess of high speed signal wires, and by the same method it works in that application it can benefit us here.
You have a radio frequency power converter running, possibly more than a few in close proximity, which you expect to work with the least interferance and noise as possible, yet aren't sold on twisting the wires to make the induced RFI/EMI common mode so that it stands some chance at rejecting it, both in the wires themselves and at the amplifier level. Have you really researched skin effect and such things?
Sure in a monoblock setup with shielded everything it will be much less apparent and certainly critical, but then we still have the "it cost .5 cent of wire" argument, while good shielded wire seems to be a little pricier. There's just no good reason not to call it the one and only right way and do it like that every single time, I put it right there along side star point ground systems.
My test rig has absolutely no hum with just maybe only 3 or 4 twists of the output wires, and it is a test rig so I'll let you know what happened when I untwist them. The speaker is 102 dB [ 1w / 1m ] efficiency so I would hear just about anything on them.
Regards,
Chris
DSP_Geek,
What you describe is a CRC circuit? Would there be a problem if there is a rapid draw of current?
Is this the same reason that choke is not recommended in the design for power supply for class D amp?
What you describe is a CRC circuit? Would there be a problem if there is a rapid draw of current?
Is this the same reason that choke is not recommended in the design for power supply for class D amp?
ackcheng said:
DSP_Geek, correct, my capacitors is 4 * 10.000uF per system,
The tweak with the resistor to produce a CRC network could cause a problem in case of high current draw. Anyway, I'll test it.
I'll try twisting my speaker wires, but my supply wires stays. They are solid cores, not easy to be twisted. BTW, I have NO hum or hiss what so ever.
Just attached another picture of the amp. "New Acoustic Dimension powered by UcD" - hmmm
/AVR300
Attachments
ackcheng said:
Choke-input power supplies require a certain minimum current to keep the voltage down, otherwise the choke impedance is insufficient to keep the voltage from rising to the peak of the rectified supply instead of the average.
If you use a CLC supply, you also can run into a resonant condition if the drawn current is too low, because you have a large resonant circuit after all, and a low current means a high impedance load, and thus little damping. Then the supply voltage becomes difficult to predict; it might even go into a chaotic regime - not the best thing to feed your amplifiers.
avr300 said:
You won't have much voltage drop through the resistors if you keep them below about 0.2 to 0.3 ohms. Musical signals are positive and negative, so if your capacitors are large enough then the draw will be averaged across the entire waveform. I just ran a PSUD simulation which indicated a 0.3 ohm resistor would reduce your full-load ripple by half, and round off the sharp edges of the waveform (which makes sense, it's an RC lowpass filter). You lose 4% of your full load supply, which equates to about 0.3 dB.
Make sure the resistors have enough power capacity to dissipate worst-case loads, typically full power at 4 ohms.
Jan-Peter said:
Strange, never had this problem(humm) with untwisted wires in my UCD stereo amps............how could this be?? I twist them now also but the main reason is the HF part/crosstalk.
I have had once a customers who complains that the amplifier hums. The wires were very close to a small transformer of a solder iron. I asked the customer to remove the loudspeaker wires at the UcD module. Short circuit the wires, and the hums stays......When he increased the distance of the loudspeaker wires and the transformer of the solder iron, the hum was decreased to zero.....
Jan-Peter
Jan-Peter