Here in the Netherlands they build a great amplifier module from Hypex (http://www.hypex.nl)the Ucd series. I have the standard serie and i used it for 2 years. The modules sounds perfect, so perfect that with time i got boring. I read a lot of the modifications with were possible but nowhere a read about using a tubebufferstage for the Ucd. Luckely a had experience with the modification of my shanling CD-T100se(http://www.hififever.com/forum/viewtopic.php?t=1738) and so i spend this chrismas holiday by modificate my Ucd amplifier.
Goal:
- Do not use the opamp inputbuffer. Direkt drive the UCD.
- Bypassing the 22uF decoppling capacitor.
- Improve the sound with some more live.
Reminders:
- Input impedance = 10k
- Source must be DC free
- Compensate 4,5 X gain of the opamp
At work:
I removed the decoppling caps of 22uf from the UCD pcb.
They were between the opampinputbuffer and the UCD powerstage. Then i connect the input sym.+ en sym - to the new points on the PCB according the picture below.
Now i only need a max 5 V rmss input signal with i can get from my shanling player by using a higher value of the I/V resistor in my tube output stage.
My shanlingplayer is the first 10 seconds not DC free so i must wait 10 sec before i press play the first time. Other wise the UCD going pumping.
If you have a tubepreamp with has 5 Vrmss output you can use that.
For the people who want to intergrate the tube stage in to the UCD housing i have a nice schematic.
This is the same SRPP circuit i use in my shanling player but with other tubes ( 6N6P ). With enough gain ( 11 X ) and working with a voltage of 40 V and higher so you can use the original UCD power supply. For the heather voltage you can use 12 V by putting two tube heaters in serie.
This SRPP circuit you can build ones a channel for RCA input and twice a channel for symmetrical input.
The sound of this SRPP circuit i perfect, see this link from Polen.
http://www.lampizator.eu/
At how about the sound the UCD are now alive. I like it.
Goal:
- Do not use the opamp inputbuffer. Direkt drive the UCD.
- Bypassing the 22uF decoppling capacitor.
- Improve the sound with some more live.
Reminders:
- Input impedance = 10k
- Source must be DC free
- Compensate 4,5 X gain of the opamp
At work:
I removed the decoppling caps of 22uf from the UCD pcb.
They were between the opampinputbuffer and the UCD powerstage. Then i connect the input sym.+ en sym - to the new points on the PCB according the picture below.
An externally hosted image should be here but it was not working when we last tested it.
Now i only need a max 5 V rmss input signal with i can get from my shanling player by using a higher value of the I/V resistor in my tube output stage.
My shanlingplayer is the first 10 seconds not DC free so i must wait 10 sec before i press play the first time. Other wise the UCD going pumping.
If you have a tubepreamp with has 5 Vrmss output you can use that.
For the people who want to intergrate the tube stage in to the UCD housing i have a nice schematic.
An externally hosted image should be here but it was not working when we last tested it.
This is the same SRPP circuit i use in my shanling player but with other tubes ( 6N6P ). With enough gain ( 11 X ) and working with a voltage of 40 V and higher so you can use the original UCD power supply. For the heather voltage you can use 12 V by putting two tube heaters in serie.
This SRPP circuit you can build ones a channel for RCA input and twice a channel for symmetrical input.
The sound of this SRPP circuit i perfect, see this link from Polen.
http://www.lampizator.eu/
At how about the sound the UCD are now alive. I like it.
Last edited:
After using the circuit for a month and build several for friends, one thing is very important. If possible let the tubestage warmup for 20 sec and then turn the UCD on. During warmup there is a lot of DC at the output of the tube this can damage the UCD.
If you intergrate the tubestage in to the UCD housing and you use one on/off switch then ad a relais contact shorten the tubestage output to ground. When switch on a timer can drive the relais after 20 sec. to open the relaisontact. The timer can be a simple circuit with NE555 or just RC and fet.
My friends and i like the sound of the 6n6 tube with the UCD.
If you intergrate the tubestage in to the UCD housing and you use one on/off switch then ad a relais contact shorten the tubestage output to ground. When switch on a timer can drive the relais after 20 sec. to open the relaisontact. The timer can be a simple circuit with NE555 or just RC and fet.
My friends and i like the sound of the 6n6 tube with the UCD.
My newest project is ready.
- More detail, instruments and artist are clearer.
- More staging also left, right and behind me plays the music.
- More midbass, the snaredrums lance the speaker conus.
- Very easy playing and nice to listen to.
This is in comparision to the audioromy fu13 in own.
Used parts:
- Brothers LU 64 db step volume controll with input select and remote. ( custom made with 20 delay ).
- 6n6p SRPP tubebuffer.
- Hypex UCD400 class D amplifier.
- Redrock 1000 Watt SMPS.
- DIY Gene aluminium case.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
- More detail, instruments and artist are clearer.
- More staging also left, right and behind me plays the music.
- More midbass, the snaredrums lance the speaker conus.
- Very easy playing and nice to listen to.
This is in comparision to the audioromy fu13 in own.
Used parts:
- Brothers LU 64 db step volume controll with input select and remote. ( custom made with 20 delay ).
- 6n6p SRPP tubebuffer.
- Hypex UCD400 class D amplifier.
- Redrock 1000 Watt SMPS.
- DIY Gene aluminium case.
Hypex UcD400 5 channel amplifier
Wanted to know how to figure out the size of the toroidal transformer you will need for 5 of the Hypex UcD400's? Also, looking for ideas on capacitors for the power supply. Was looking at Mundorf since they have a good reputation for use in speakers. I am new to this but have always wanted to build my own amplifier and this looks like the best way to start and learn. Any help is welcomed.
Wanted to know how to figure out the size of the toroidal transformer you will need for 5 of the Hypex UcD400's? Also, looking for ideas on capacitors for the power supply. Was looking at Mundorf since they have a good reputation for use in speakers. I am new to this but have always wanted to build my own amplifier and this looks like the best way to start and learn. Any help is welcomed.
Ceibal, as you see i do not use toroidal transformers anymore.
The SMPS works great and performs even better as the toroidal transformer setup.
Why i use SMPS now:
- As good or even better sounding as toroidal transformer ( less humm ).
- Lighter in weight.
-Easy to use and install.
- Cheaper ( for 2000 Watt you need 2 x Redock 1000Watt SMPS cost € 280,- with the toroidal setup it cost at least € 500,- ).
In your case use 2 Redrock 1000Watt SMPS and you do not have to doubt over with capacitors you have to use. Use one SMPS for the two front channels and the other SMPS for the mid and surround channels asuming you use it in a dolby setup.
The SMPS works great and performs even better as the toroidal transformer setup.
Why i use SMPS now:
- As good or even better sounding as toroidal transformer ( less humm ).
- Lighter in weight.
-Easy to use and install.
- Cheaper ( for 2000 Watt you need 2 x Redock 1000Watt SMPS cost € 280,- with the toroidal setup it cost at least € 500,- ).
In your case use 2 Redrock 1000Watt SMPS and you do not have to doubt over with capacitors you have to use. Use one SMPS for the two front channels and the other SMPS for the mid and surround channels asuming you use it in a dolby setup.
No need for extra capacitors. It is even possible to use one SMPS for the five amps. Piek output power is 2000Watt. You can place you order at the factory.
Just email what you need and ask for the price incl. shipment.
Ad to the order that you need +/- 60Volt version for the UCD400.
http://www.redrocksaudio.es/files/SMPS6060PFCen.pdf
http://www.redrocksaudio.es/
Just email what you need and ask for the price incl. shipment.
Ad to the order that you need +/- 60Volt version for the UCD400.
http://www.redrocksaudio.es/files/SMPS6060PFCen.pdf
http://www.redrocksaudio.es/
Hypex UcD400 5 channel amplifier
My concern is the quality of the capacitors it uses. Do you know the brand or any specs on them? I know from other forums that the capacitor on the power supply can make a big difference in the sound quality. Have you compared this power supply to others? Sounds good but want to insure this is the best possible way to go.
My concern is the quality of the capacitors it uses. Do you know the brand or any specs on them? I know from other forums that the capacitor on the power supply can make a big difference in the sound quality. Have you compared this power supply to others? Sounds good but want to insure this is the best possible way to go.
Re: Hypex UcD400 5 channel amplifier
I do not know the brand of them. Next time i disamble the amp i will look for you. I now they have a much lower value then i normal use in normal powersupply's for the UCD modules. It is not my goal to build the best amplifier but this one sounds for me the best i heard i my 40 years of audio experience. Looking on the budget it is the biggest bang for your bucks. Where do you get a 1000Watt( 2000Watt max ) power supply for € 130,-. There will always a better solution. But enjoying the present one is great.
It has two connectors a terminal. You can build a powerrail( 3 times, +,- and ground of copperstrip ) from were you connect the amps.
I use the same principle but the above diagram is optimized for 120 V and a output impedance of 8k2. I used 68 Ohm resistors no resistor in the anode. And two 100uF/50V Nichicon Gold Muse Capacitors antiparallel bypassed with Wima 100nF/250V as output capacitor. I will place diagram soon.
Ceibal said:
I do not know the brand of them. Next time i disamble the amp i will look for you. I now they have a much lower value then i normal use in normal powersupply's for the UCD modules. It is not my goal to build the best amplifier but this one sounds for me the best i heard i my 40 years of audio experience. Looking on the budget it is the biggest bang for your bucks. Where do you get a 1000Watt( 2000Watt max ) power supply for € 130,-. There will always a better solution. But enjoying the present one is great.
Ceibal said:
It has two connectors a terminal. You can build a powerrail( 3 times, +,- and ground of copperstrip ) from were you connect the amps.
revintage said:
I use the same principle but the above diagram is optimized for 120 V and a output impedance of 8k2. I used 68 Ohm resistors no resistor in the anode. And two 100uF/50V Nichicon Gold Muse Capacitors antiparallel bypassed with Wima 100nF/250V as output capacitor. I will place diagram soon.
An externally hosted image should be here but it was not working when we last tested it.
Hi Koifarm,
Oooops! This makes it even worse as according to my calculations current is now ca 4mA.
THD of 9V into 1,8k will be gross and probably over 10%! Have you done any measurments?
Why not try an 6N30P instead as these are more linear at this extremely low voltage. It will draw about 12mA in this circuit.
Also a B+ of at least the double would be fine.
Oooops! This makes it even worse as according to my calculations current is now ca 4mA.
THD of 9V into 1,8k will be gross and probably over 10%! Have you done any measurments?
Why not try an 6N30P instead as these are more linear at this extremely low voltage. It will draw about 12mA in this circuit.
Also a B+ of at least the double would be fine.
revintage said:
I do not now how you calculatebut i use this:
http://www.ict-net.net/tube.xls
I can not hear any distorsion at high levels. So it must below 0.5%.
I do not measure only if there problems. If my ears tell me it sounds great, why measure? Great specs says really nothing about the sound.
Hypex UcD400 5 channel amplifier
I was reading about switch mode power supplies and was wondering about some of the disadvantages. My book state that they have very high levels of EMI emissions, poor reliability and poor transient current response. Of course, this book was written around 1999 and allot has changed but was curious if they have solved these issues? Also, with my limited electronic know how, I am unsure how to build the power rail. I like challenges but I will need a way to learn how to build it. Any ideas as to where I can get a good idea of how to do this?
I was reading about switch mode power supplies and was wondering about some of the disadvantages. My book state that they have very high levels of EMI emissions, poor reliability and poor transient current response. Of course, this book was written around 1999 and allot has changed but was curious if they have solved these issues? Also, with my limited electronic know how, I am unsure how to build the power rail. I like challenges but I will need a way to learn how to build it. Any ideas as to where I can get a good idea of how to do this?
Hi Koifarm,
I am sorry to disappoint you but the spreadsheet is useless for this. With 30V over each triode it won´t work without gross distortion.
You have to check tubecurves or use Spice.
This is agood starting point:
http://klausmobile.narod.ru/testerfiles/6n6p.htm
I can help you, just drop an E-mail.
Your circuit has potential but you must get the figures right
!
I am sorry to disappoint you but the spreadsheet is useless for this. With 30V over each triode it won´t work without gross distortion.
You have to check tubecurves or use Spice.
This is agood starting point:
http://klausmobile.narod.ru/testerfiles/6n6p.htm
I can help you, just drop an E-mail.
Your circuit has potential but you must get the figures right
!
Lars let me see your alternetive with the right figures. And probaly i will tell you it is one i tested before.
Tested more then 100 SRPP setups on my shanling CD- T100se. On this player i can build two SRPP output stages and do ABX testing with a lot of persons. They point if they can hear the difference or not. I do this for 3 years. After this period i like the SRPP setup. I also tested different anode voltage and different current setup's.
The difference between 120V or 60V was not notable for every person. Below 49 V the tube do not work fine anymore and it will be notable.
The spreadsheet is a guideline, your ears and emotion are the finetuners. But maybe you can tell me something new.
Ceibal, this SMPS is made for audio. It is simple to make a nice powerrail. Take 3strips of copper( 2 x 12 mm or so ) mount them on isolators. Connect from the powersupply the +, - and ground to them. Then tap from the powerrail the +. -, and ground for each UCD module. I hope you get the picture.
Tested more then 100 SRPP setups on my shanling CD- T100se. On this player i can build two SRPP output stages and do ABX testing with a lot of persons. They point if they can hear the difference or not. I do this for 3 years. After this period i like the SRPP setup. I also tested different anode voltage and different current setup's.
The difference between 120V or 60V was not notable for every person. Below 49 V the tube do not work fine anymore and it will be notable.
The spreadsheet is a guideline, your ears and emotion are the finetuners. But maybe you can tell me something new.
Ceibal, this SMPS is made for audio. It is simple to make a nice powerrail. Take 3strips of copper( 2 x 12 mm or so ) mount them on isolators. Connect from the powersupply the +, - and ground to them. Then tap from the powerrail the +. -, and ground for each UCD module. I hope you get the picture.
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