I too have purchased two of these boards and started modding them slightly. I intended to replace the input capacitors, among other things ofcourse, but was wondering if it would be possible to just remove them all together?
Thing is, they'll be used as poweramps for a 8 channel dsp amp where the signal will be fed bij two minidsp boards wich already got pretty decent 470uF Nichicon Muse output capacitors.
Annyone tried such a thing yet? Can't get less signal alteration from the caps then by removing them altogether i thought.
Greetings, Reinder
Did you tried providing an enclosure to your amp already ?
I see your dsp is going to protect your speakers but how you are going to protect your source from the dc bias?
Hi Virpz,
I'll have the analog sources connected directly to the minidsp 2*4 boards and the digital sources to a minidigi board. From there the signal passes through the amp to the speakers. With all the signals traveling through the minidsp unit & these having beefy caps on them (470uF is a lot if you ask me, considering where talking 1,5v signals max here) I'm not sure I understand what you mean with protecting the sources? Perhaps I'm missing something here, not an electrician.
Greetings Reinder
Edit:
And some pics of the work in progress. Replaced the buffer caps with Rubycon ZL 1800uF & Vishay 1839 0,1uF bypass. The inductors with Wurth 4,7uH shielded smds parts, had to solder legs to them for easy through hole mounting and mounted them on the back of the board because there's more space there. Shorted the resistors for the dc Offset part of the board. Still have to replace the caps for the low pass filter with WIMA mkp4's and then'I'll probably leave it at that for now, possibly add some Clarity Caps as input caps if the experiment with no input caps isn't satisfactionary.
I'll have the analog sources connected directly to the minidsp 2*4 boards and the digital sources to a minidigi board. From there the signal passes through the amp to the speakers. With all the signals traveling through the minidsp unit & these having beefy caps on them (470uF is a lot if you ask me, considering where talking 1,5v signals max here) I'm not sure I understand what you mean with protecting the sources? Perhaps I'm missing something here, not an electrician
.Greetings Reinder
Edit:
And some pics of the work in progress. Replaced the buffer caps with Rubycon ZL 1800uF & Vishay 1839 0,1uF bypass. The inductors with Wurth 4,7uH shielded smds parts, had to solder legs to them for easy through hole mounting and mounted them on the back of the board because there's more space there. Shorted the resistors for the dc Offset part of the board. Still have to replace the caps for the low pass filter with WIMA mkp4's and then'I'll probably leave it at that for now, possibly add some Clarity Caps as input caps if the experiment with no input caps isn't satisfactionary.
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Hi Virpz,
I'll have the analog sources connected directly to the minidsp 2*4 boards and the digital sources to a minidigi board. From there the signal passes through the amp to the speakers. With all the signals traveling through the minidsp unit & these having beefy caps on them (470uF is a lot if you ask me, considering where talking 1,5v signals max here) I'm not sure I understand what you mean with protecting the sources? Perhaps I'm missing something here, not an electrician
Greetings Reinder
I still green so I'm not sure if it is safe. Anyway you might want to have a reading here
Mod list looking good. Please, share the results.
[]'s
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Thanks to everyone . Got a Sure 4x100. My first dip into class D turned out better than expected. Primarily, got into these because of their cost for a multichannel active setup. Removing DC at the outputs was a notable improvement. I also found that bypassing the tank caps to the nth degree, i.e. 1000>100>10>1>.1>.01>.001 better than doubling or tripling the capacitance. PSU is a Connexelectronics SMPS300R at 30v being fed by differential 250v(125Vx2) AC dedicated line(BX Cable) and dedicated earth ground. Replaced the input caps with 2uf SCR Tin Foil caps from my stash connected directly to the pins of the daughterboard bypassing RCA connectors. Until recently did not what to spend anymore on it as I was just recycling what I had on hand. I finally got some Micrometals 106-2 inductors currently at 10uh. I also have .47uf VitaminQ PIO caps on its way. I'll let you know how it sounds.
Anyway, what I really wanted to ask is... do class D amps have a certain sound? To me, the sound is more mechanical, for the lack of a better word than electronic. Sound of switching devices?
. Got a Sure 4x100. My first dip into class D turned out better than expected. Primarily, got into these because of their cost for a multichannel active setup. Removing DC at the outputs was a notable improvement. I also found that bypassing the tank caps to the nth degree, i.e. 1000>100>10>1>.1>.01>.001 better than doubling or tripling the capacitance. PSU is a Connexelectronics SMPS300R at 30v being fed by differential 250v(125Vx2) AC dedicated line(BX Cable) and dedicated earth ground. Replaced the input caps with 2uf SCR Tin Foil caps from my stash connected directly to the pins of the daughterboard bypassing RCA connectors. Until recently did not what to spend anymore on it as I was just recycling what I had on hand. I finally got some Micrometals 106-2 inductors currently at 10uh. I also have .47uf VitaminQ PIO caps on its way. I'll let you know how it sounds.Anyway, what I really wanted to ask is... do class D amps have a certain sound? To me, the sound is more mechanical, for the lack of a better word than electronic. Sound of switching devices?
Thanks to everyone
Anyway, what I really wanted to ask is... do class D amps have a certain sound? To me, the sound is more mechanical, for the lack of a better word than electronic. Sound of switching devices?
By the nth degree you mean that you bypassed the 1000uF with 10uF caps ?
I know what you mean. Although I love the sound of my T amps I still have the feeling that something is missing or the sound is "too correct" specially with the Tk2050 as I found that with the ta2020 sound is more warm and somehow natural. I was thinking about a cheap tube pre amp to correct that but I haven't heard anything that tells if it is really worth.
[]'s
I have read through the blogs on theses amps and altough they seam to sound good they are unreliable and can run hot.
Just a thought, they are as cheap as chips so why don't you guys buy two boards and run them as a duo mono set up with input to one channel only. Therefore they should run cooler, sound better (Duo mono set up, no crosstalk) and if one channel is defective or blows up!! switch to the other channel. Anyway that's what I am going to do .
So you're going to buy two 4 channel boards, and parallel all 4 channels on each board for a 2 channel setup? I was thinking about getting a 4 channel board and paralleling to make it a 2 channel board. The spec sheet for the TK2050 says that this will double the power available at .01% THD to 70 watts, vs 35 watts @ .01% THD for 2 channels per chip. There were no specs for using 4 chips for one channel, I don't know if that is a good idea or not.
Has anyone measured one of these boards for crosstalk, THD, etc? I haven't seen any measurements, and it would be great to see how close they get to the chip specs.
-Aaron.
Hi,
I got 2 of these 4 channels They said 4x100 watts ,I haven't tested them or modded them they sound good as they are,I did put 2 fans on each one because they are in a warm environment,I suggest at least one fan,I removed them from a computer PS and use a wallwart to run them ,about 8 volts keeps them quiet.I am running a active 3 way with summed sub,I use 32volt supplies the fan in it hasn't come on yet.
I did add caps about 10,000 on the supplies it helped the bass, better and deeper,I would like to here your results when you get it working!
I got 2 of these 4 channels They said 4x100 watts ,I haven't tested them or modded them they sound good as they are,I did put 2 fans on each one because they are in a warm environment,I suggest at least one fan,I removed them from a computer PS and use a wallwart to run them ,about 8 volts keeps them quiet.I am running a active 3 way with summed sub,I use 32volt supplies the fan in it hasn't come on yet.
I did add caps about 10,000 on the supplies it helped the bass, better and deeper,I would like to here your results when you get it working!
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Mods list
Since the information about these 4x100 boards is very disperse I will put down a list of mods I've done to my board.
MODS ON THE MOTHER BOARD AA-AB009 v1.2
Tank caps:
- Replaced tank caps with Panasonic FM and FC caps by 1000uF>1000uF>100uF>10uF>1uF . I've made new holes onto the pcb to accommodate the new caps.
Input
- Replaced input caps c25, c26, c27, c28 with mundorfs mcap 450v 2.2uf bypassed with 10000pF polyestyrene .
- Removed the resistors ; r10, r13, r6, r11, r12, r8, r17, r14, r7, r16, r15, r9 and connected the inputs directly to their respective pins on the daughter board. Take a look here
* Pay attention that by doing this mod the MAX input signal the board can take is 2000mV !
-Replaced c15 and c20 with wima mks2 63v 0.1uF
-Replaced c24 and c23 with wima mks2 63v 1uF
- ch1 to pin 6
- ch2 to pin 8
- ch3 to pin 13
- ch4 to pin 15
If you want to use the input terminals (not RCA ) after that mod you should provide their path with input caps !
Output filters
For low pass filter I have
- L= 6.5uH ( selfwound 16AWG air coils )
- C= 0.68uF (RIFA PHE426 0.68uF 15 legspam 15mm. I made new holes on the PCB to solder )
Zobel High pass
- R= 10 Ohms 4W MOX
- C= 0.47uF RIFA PHE426 250v.
You should have a reading here and simulate here
MODS ON THE DAUGTHER BOARD AA-AB123V100
Dc offset and tank caps to TC2000
To successfully adjust the dc offset you have to remove and bridge r26, r33, r11, r19, r54, r61, r39, r47.
While adjusting DC offset keep in mind that trims are not in series with outputs. R28 adjusts channel 2, r13 channel 1, r56 channel 4 and so on.
To adjust you sould disconnect your speakers and connect some pure resistive load to the outputs ( 4 to 10 ohms, 1 Watt resistor ) along with you multimeter, set the multimeter to read mV and have NO input signal connected to the board. Turn the board on an you can adjust the dc offset. Adjust to 20mW or minus, less is better.
*Anytime you change the power supply you have to adjust DC offset again.
Added 200uF to c1. The negative pin on c1 is facing its number ( c1 ) on daugther board and input caps on the motherboard .
Added 200uF to c11. The negative pin on c1 is facing tp2050 while the positive is facing lm317k.
Power supply
If you have a meanwell power supply you should drop a film cap connecting one leg to GROUND and another to COM . I used 0.47uF 630vdc . That mod was suggested by dr_vega on the 2x100 wiki as you can see hereand will really help on getting rid of some noise.
Mods that REALLY improved the sound:
- Output inductors. As with the ta2020, things really improved after I replaced stock inductors with air cored ones. I tried many different combinations of lcr filters. Coils from 7uH to 4uH gave the best results. That is the first mod that I will do whenever I buy another tk2050 board.
- Replacing output filter caps with the rifa phe 426 REALLY improved the sound. I like those caps much better than wima mks or mkp series. Keep in mind that matching the filters to your speakers is also important if you want to anchieve the best results. Overall sound is more natural, cymbals are real and those caps are cheap and very good quality.
- Panasonic FM and FC caps are well know for their good price/value and they did a great job of adding a little more bass.
- cap connected to COM and GROUND on the meanwell psu. By doing this mod I got rid of 60% of noise.
In short those are the 4 mods that in my opinion will really improve the sound comming out of your Sure 4x100 board. For those complaining of the lack of bass I must say that I have plenty of a tight, well controlled bass and everything else sounds amazing. I have purchased a "tk2050" ( tc2000 +sta510 ) , non paralleled design from a very popular and hyped chinese seller and I must say that my sure 4x100 after some mods sounds MUCH better to me.
Cheers
Since the information about these 4x100 boards is very disperse I will put down a list of mods I've done to my board.
MODS ON THE MOTHER BOARD AA-AB009 v1.2
Tank caps:
- Replaced tank caps with Panasonic FM and FC caps by 1000uF>1000uF>100uF>10uF>1uF . I've made new holes onto the pcb to accommodate the new caps.
Input
- Replaced input caps c25, c26, c27, c28 with mundorfs mcap 450v 2.2uf bypassed with 10000pF polyestyrene .
- Removed the resistors ; r10, r13, r6, r11, r12, r8, r17, r14, r7, r16, r15, r9 and connected the inputs directly to their respective pins on the daughter board. Take a look here
* Pay attention that by doing this mod the MAX input signal the board can take is 2000mV !
-Replaced c15 and c20 with wima mks2 63v 0.1uF
-Replaced c24 and c23 with wima mks2 63v 1uF
- ch1 to pin 6
- ch2 to pin 8
- ch3 to pin 13
- ch4 to pin 15
If you want to use the input terminals (not RCA ) after that mod you should provide their path with input caps !
Output filters
For low pass filter I have
- L= 6.5uH ( selfwound 16AWG air coils )
- C= 0.68uF (RIFA PHE426 0.68uF 15 legspam 15mm. I made new holes on the PCB to solder )
Zobel High pass
- R= 10 Ohms 4W MOX
- C= 0.47uF RIFA PHE426 250v.
You should have a reading here and simulate here
MODS ON THE DAUGTHER BOARD AA-AB123V100
Dc offset and tank caps to TC2000
To successfully adjust the dc offset you have to remove and bridge r26, r33, r11, r19, r54, r61, r39, r47.
While adjusting DC offset keep in mind that trims are not in series with outputs. R28 adjusts channel 2, r13 channel 1, r56 channel 4 and so on.
To adjust you sould disconnect your speakers and connect some pure resistive load to the outputs ( 4 to 10 ohms, 1 Watt resistor ) along with you multimeter, set the multimeter to read mV and have NO input signal connected to the board. Turn the board on an you can adjust the dc offset. Adjust to 20mW or minus, less is better.
*Anytime you change the power supply you have to adjust DC offset again.
Added 200uF to c1. The negative pin on c1 is facing its number ( c1 ) on daugther board and input caps on the motherboard .
Added 200uF to c11. The negative pin on c1 is facing tp2050 while the positive is facing lm317k.
Power supply
If you have a meanwell power supply you should drop a film cap connecting one leg to GROUND and another to COM . I used 0.47uF 630vdc . That mod was suggested by dr_vega on the 2x100 wiki as you can see hereand will really help on getting rid of some noise.
Mods that REALLY improved the sound:
- Output inductors. As with the ta2020, things really improved after I replaced stock inductors with air cored ones. I tried many different combinations of lcr filters. Coils from 7uH to 4uH gave the best results. That is the first mod that I will do whenever I buy another tk2050 board.
- Replacing output filter caps with the rifa phe 426 REALLY improved the sound. I like those caps much better than wima mks or mkp series. Keep in mind that matching the filters to your speakers is also important if you want to anchieve the best results. Overall sound is more natural, cymbals are real and those caps are cheap and very good quality.
- Panasonic FM and FC caps are well know for their good price/value and they did a great job of adding a little more bass.
- cap connected to COM and GROUND on the meanwell psu. By doing this mod I got rid of 60% of noise.
In short those are the 4 mods that in my opinion will really improve the sound comming out of your Sure 4x100 board. For those complaining of the lack of bass I must say that I have plenty of a tight, well controlled bass and everything else sounds amazing. I have purchased a "tk2050" ( tc2000 +sta510 ) , non paralleled design from a very popular and hyped chinese seller and I must say that my sure 4x100 after some mods sounds MUCH better to me.
Cheers
hi Virpc,
I am going to start on my 4 x100 sure soon,so what are the tank caps ? I think I understand all the rest,I might ask for some help.if you don't mind ,would you take a few more pics of the mods and post them ,Thanks for the time and help!
I got some coils ,I'll look them up and post back what they are.
Where did you get the rest of the parts anywhere special?
I am going to start on my 4 x100 sure soon,so what are the tank caps ? I think I understand all the rest,I might ask for some help.if you don't mind ,would you take a few more pics of the mods and post them ,Thanks for the time and help!
I got some coils ,I'll look them up and post back what they are.
Where did you get the rest of the parts anywhere special?
pls help!!
I have same issue (completely new to electronics but really willing to do all these steps to improve my board)
cheers
ps: where do I measure the offset-voltage?
I'm new to this thread and have a question regarding use of laptop brick power supplies for this amp. I have tons of 19V 4.7 Amp bricks lying around. Can I gang them in parallel to get higher current ratings? I am probably going to add a big fat capacitor in common before feeding into amplifier. If someone has discussed this already, pardon the repeat question. Thanks.
Maintaining phase
If you wish to maintain absolute phase, you can reverse the speaker connections. However, you must use 2 wires per channel since this is a full wave class D design in which the negative speaker outputs are NOT grounded.
I have lived with one of these boards for over a year now. It still sounds great. The board gets a touch warm at idle BUT it does not heat up further unless driven very hard. I keep mine in a close plastic box, the outside of which is just barely warm to the touch.
If you wish to maintain absolute phase, you can reverse the speaker connections. However, you must use 2 wires per channel since this is a full wave class D design in which the negative speaker outputs are NOT grounded.
I have lived with one of these boards for over a year now. It still sounds great. The board gets a touch warm at idle BUT it does not heat up further unless driven very hard. I keep mine in a close plastic box, the outside of which is just barely warm to the touch.
Thanks for the info on phase.
Regards heating. The box I used had poor ventilation. With the lid closed the unit used to get too hot for comfort. I made up some extra brackets so that the aluminium lid contacts the heatsink when closed. It runs very cool now.
Great amplifier for the money. I upgraded the coupling and power supply caps and it is magic.
Regards heating. The box I used had poor ventilation. With the lid closed the unit used to get too hot for comfort. I made up some extra brackets so that the aluminium lid contacts the heatsink when closed. It runs very cool now.
Great amplifier for the money. I upgraded the coupling and power supply caps and it is magic.
Greetings!
I'm new to the forum and rather new to these amps.
Summer is approaching and a portable rig is planned. The Sure 4x100 is on my 'want' list, with a few questions:
1) Should I choose the version with the fan or without the fan? (I cannot figure out any differences?)
2) I'm thinking of the idea of using a cheap DC-DC boost to jank up the input voltage to around 27V. Would this one work at all? (or potential problems following/special precautions?) DC DC Converter 10 32V to 12 35V 150W Boost Power Supply Module for Notebook | eBay
Cheers /
I'm new to the forum and rather new to these amps.
Summer is approaching and a portable rig is planned. The Sure 4x100 is on my 'want' list, with a few questions:
1) Should I choose the version with the fan or without the fan? (I cannot figure out any differences?)
2) I'm thinking of the idea of using a cheap DC-DC boost to jank up the input voltage to around 27V. Would this one work at all? (or potential problems following/special precautions?) DC DC Converter 10 32V to 12 35V 150W Boost Power Supply Module for Notebook | eBay
Cheers /
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