When I got my last 4x100, I was a bit gun shy and brought it up with a 12v wall wort, then a laptop supply similar to your 19v 5A. It sounded pretty good at 19-20v at low but reasonable volume maybe 5-20 watts. The final act occurred a day after connecting the Meanwell supply with 12A capability. It was not being played loud when it died.
None of the 3 failed amps had the short Sure describes on the input diode. My guess would be that the first 2 modules had devices suffer shoot through (both output drivers on briefly) perhaps due to the sequencing of the 5 volt regulator that runs the protection circuits. The last module had the most dramatic damage with pins blown right off the device. At first I though it may have been static when I touched the heatsink, but on reflection it could also have been an intermittent connection that was mechanically affected by my touching the heatsink. If you look at the diameter of the pins and the width of some of the pads beneath then, it is clear that there is no margin for error with a high current supply. Incidentally, the last module was shipped with a charred snubber resistor which to me means oscillation but thats just conjecture.
Ideally the 12A would be divided over four channels and multiple little pins and pads in parallel but considering the complexity of 4 300-400khz switching at very high but brief currents its really amazing how well these things work when everything is right. Yes running at the highest voltage and current gives the ability to punch it up with super transients and clarity. My sense is that the module sounded pretty good at moderate volume with the laptop supply and probably would still be running today,
None of the 3 failed amps had the short Sure describes on the input diode. My guess would be that the first 2 modules had devices suffer shoot through (both output drivers on briefly) perhaps due to the sequencing of the 5 volt regulator that runs the protection circuits. The last module had the most dramatic damage with pins blown right off the device. At first I though it may have been static when I touched the heatsink, but on reflection it could also have been an intermittent connection that was mechanically affected by my touching the heatsink. If you look at the diameter of the pins and the width of some of the pads beneath then, it is clear that there is no margin for error with a high current supply. Incidentally, the last module was shipped with a charred snubber resistor which to me means oscillation but thats just conjecture.
Ideally the 12A would be divided over four channels and multiple little pins and pads in parallel but considering the complexity of 4 300-400khz switching at very high but brief currents its really amazing how well these things work when everything is right. Yes running at the highest voltage and current gives the ability to punch it up with super transients and clarity. My sense is that the module sounded pretty good at moderate volume with the laptop supply and probably would still be running today,
If anyone still interested these seems Wurth WE-PD Type XXL Metal Base
I've redone the search on Distrelec with 10uH, the maximum available current rating is 7.10 A.
The image in the datasheet is identical to the photo, IMHO.
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Good coils
Those are good coils. They can sound very close to a good air core if you pick a smaller value. I'm finishing up listening tests to chose between the 3.5 and 4.7uH XXL. I will post my final output filter schematic on the 2X100 thread in a couple weeks.
Firstly, just let me pass on my thanks for the thread so far - I have learned a lot (being relatively new to the amp part of DIY audio!). Just as background, I have one of the 4x 100W boards that I intend to use with an active crossover to power a set of home made 2 way speakers.
My question for you guys is about the power supply. I have a left over chipamp.com power supply board:
DIY Chip Amplifier Kits, PCB's, Components and Information.
which I was thinking about using with this project. I was thinking a 18V+18V transformer would give a final voltage of about 23V, and that'd be appropriate. The output of that board would give 2*0-23V supplies. In the case of a chipamp these are used to make a -23-0-23V supply, but I was thinking that I could place them in parallel to make a 0-23V supply with a larger capacity. I can get 160VA and 300VA transformers locally - any suggestions? In the wisdom of the mob - does this sound workable? (as you can tell - I am not an expert in these matters).
Thanks in advance! Can't wait to get it up and running.
My question for you guys is about the power supply. I have a left over chipamp.com power supply board:
DIY Chip Amplifier Kits, PCB's, Components and Information.
which I was thinking about using with this project. I was thinking a 18V+18V transformer would give a final voltage of about 23V, and that'd be appropriate. The output of that board would give 2*0-23V supplies. In the case of a chipamp these are used to make a -23-0-23V supply, but I was thinking that I could place them in parallel to make a 0-23V supply with a larger capacity. I can get 160VA and 300VA transformers locally - any suggestions? In the wisdom of the mob - does this sound workable? (as you can tell - I am not an expert in these matters).
Thanks in advance! Can't wait to get it up and running.
Hey John thanks for that detailed reply, would you think it'd be a better idea to go with a ~24 volt meanwell supply rather than the 27V one? And would it help if i used a 8A quick blow fuse for the input of the amp?
Also i'm thinking of gutting an old 24 port 19" rack mountable ethernet hub and mounting this inside there. When doing so, should I connect the ground wire to the case of the hub?
Also i'm thinking of gutting an old 24 port 19" rack mountable ethernet hub and mounting this inside there. When doing so, should I connect the ground wire to the case of the hub?
loleskater,
Mounting in a case would reduce danger from static, shorts and mechanical stress. I would also check the contact pattern of the heat sink while replacing the white heatsink paste with some of the silver high performance stuff that computer geeks use.
I don't think there would be that much difference between 24 and 27V to the life of a good module. A fan would give some extra safety margin. As for a fuse, I think it would be a race to melting between the chip dice and the fuse. The internal protection circuitry is usually fast enough. A fuse might help the speaker survive, although none of the failures I experienced have put big current on the speakers.
My thinking with class D now is if you value reliability, use a 100W amp for 30W listening and get a 400W module if you are really playing music at 100W.
Mounting in a case would reduce danger from static, shorts and mechanical stress. I would also check the contact pattern of the heat sink while replacing the white heatsink paste with some of the silver high performance stuff that computer geeks use.
I don't think there would be that much difference between 24 and 27V to the life of a good module. A fan would give some extra safety margin. As for a fuse, I think it would be a race to melting between the chip dice and the fuse. The internal protection circuitry is usually fast enough. A fuse might help the speaker survive, although none of the failures I experienced have put big current on the speakers.
My thinking with class D now is if you value reliability, use a 100W amp for 30W listening and get a 400W module if you are really playing music at 100W.
According to the datasheet of TK2050 at 24V it seems the amount of good power it can provide is up to around 30W (guesstimate). Coincidence or what? 😀
hello all,
I got my 4X100W today with the Mainwell 24V 350W power supply. It sound pretty good. I'm using it with a HTPC. No smoke, no sparks for the moment...😉
I'have done a little CR here but this is in french (as you can read it's more easy for me 😀).
my conclusion is : very good for this price.
I got my 4X100W today with the Mainwell 24V 350W power supply. It sound pretty good. I'm using it with a HTPC. No smoke, no sparks for the moment...😉
I'have done a little CR here but this is in french (as you can read it's more easy for me 😀).
my conclusion is : very good for this price.
Hello, nice write-up, I think - my French is not very good though.
I hope you share more impressions about the amp.
Relace Input and Output Caps
I am thinking in changing the input and output caps (blue ones) with wima mks2 1.0uf. Opinions?
😕
I am thinking in changing the input and output caps (blue ones) with wima mks2 1.0uf. Opinions?
😕
hi
i ordered a 2*100w from sure. the one with the fan on top but the one that just arrived looked just the same as the 4*100w. whats the difference?
i ordered a 2*100w from sure. the one with the fan on top but the one that just arrived looked just the same as the 4*100w. whats the difference?
i know i have the 2*100w version but the layout is the same.i managed to get my offset from 374 and 118 to 11.2 and 2.3. first i got them as low as possible with the resistors as standard. for the first channel i got it down to 310and then left the trim pot in that position while i drew graphite pencil across the resistors. trimming the pot first makes it easier to find the spot right in the middle befor you make the pots twitchy
Do you need to use some other heatsink with the amp when you are lowering the offset voltage?
Or dont the chips heat up if they are just sitting at idle with no input?
Or dont the chips heat up if they are just sitting at idle with no input?
it took me about five minutes to set the trimmers and the chips were still only warm at that point
Im new to the DIY audio scene, I have tried searching but still dont understand what the offset voltage is for and why you adjust it?
Also I how well do these amps run large speakers Im looking at using a 4 x 100 board to bi amp a pair of mission speakers they are rated @ 150w / 92db sensitivity. each speaker has 3 x 8 inch woofers and a tweeter.
Thanks
DC offset is the difference in the + and the - on your speaker. This is the voltage that always loads your speakers, so your speakers will be loaded, which causes less lifetime and maybe worse sound.
Best to set DC offset to zero, as speakers work on AC.
Best to set DC offset to zero, as speakers work on AC.
Build a 16 channel amp out of 4 of these boards?
I'm thinking of building a pretty big unit out of these for whole house distributed audio, and wanted to get some feedback from those of you who know the intricacies of these amps.
I'm creating seven zones (kitchen, 3 bedrooms, 2 baths, backyard) with used airport expresses on ebay. The output of those will go to these amplifiers, and then to some ceiling speakers I'm installing. The whole system will be controlled by the computer / iphone / ipod touch. I was originally planning on building seven amps and mounting them in each room along with each airport express, but then I realized that would be needless and ugly. Then when I saw the 4*100 amp, I figured I could cut down on cost and make it look better by mounting all the amps - 4 4*100 boards for 16 channels (14 used) - in a single rack mount chassis with my network gear.
I could just get two 7.1 receivers off of ebay, but it would cost just as much, probably wouldn't sound as good, and hey, I need a fun electronics project that has the potential to annoy the wife and amaze the friends 😉
Then I came and read this thread, and it seems some mods are much harder to do on this version of the board. And to top it all off, I just went to sure electronics site, and they say they are out of stock of the 4*100 boards. So, I have a few questions:
1. Are these 4*100 boards production ready yet, or are they still having major issues with them?
I probably will lift the input limiters, and I'll need to adjust the input gain (probably with constant resistors rather than a pot) so as to never clip from the output of the airport expresses. Will I have to adjust the DC offset?
2. The 'manual' if you want to call it that mentions a 'sleep / mute' function. Is this something that is already implemented when the audio signal goes to zero for a while, or do I need to design a circuit for this functionality if I want to use it?
3. What current of power supply would i need to drive 4 of these boards in a single chassis, or how many of the Meanwell 350W supplies would I need?
It might be cheaper just to get 2-4 of the 350W Meanwell supplies, the higher current supplies I'm finding are pretty expensive:
SE-1500-27, Mean Well SE-1500-27
RSP-1000-27, Mean Well RSP-1000-27
SP-750-27, Mean Well SP-750-27
SE-6000-27, Mean Well SE-600-27
I don't anticipate running this thing full bore, I just want headroom so that music with lots of dynamic range sounds good. If I turned all the speakers on in the house full blast, I would probably run outside because it would be too loud.
4. Does the fact that they are out of stock mean they are changing them somehow? What should I know about what they are changing, if anyone knows?
Thanks!
I'm thinking of building a pretty big unit out of these for whole house distributed audio, and wanted to get some feedback from those of you who know the intricacies of these amps.
I'm creating seven zones (kitchen, 3 bedrooms, 2 baths, backyard) with used airport expresses on ebay. The output of those will go to these amplifiers, and then to some ceiling speakers I'm installing. The whole system will be controlled by the computer / iphone / ipod touch. I was originally planning on building seven amps and mounting them in each room along with each airport express, but then I realized that would be needless and ugly. Then when I saw the 4*100 amp, I figured I could cut down on cost and make it look better by mounting all the amps - 4 4*100 boards for 16 channels (14 used) - in a single rack mount chassis with my network gear.
I could just get two 7.1 receivers off of ebay, but it would cost just as much, probably wouldn't sound as good, and hey, I need a fun electronics project that has the potential to annoy the wife and amaze the friends 😉
Then I came and read this thread, and it seems some mods are much harder to do on this version of the board. And to top it all off, I just went to sure electronics site, and they say they are out of stock of the 4*100 boards. So, I have a few questions:
1. Are these 4*100 boards production ready yet, or are they still having major issues with them?
I probably will lift the input limiters, and I'll need to adjust the input gain (probably with constant resistors rather than a pot) so as to never clip from the output of the airport expresses. Will I have to adjust the DC offset?
2. The 'manual' if you want to call it that mentions a 'sleep / mute' function. Is this something that is already implemented when the audio signal goes to zero for a while, or do I need to design a circuit for this functionality if I want to use it?
3. What current of power supply would i need to drive 4 of these boards in a single chassis, or how many of the Meanwell 350W supplies would I need?
It might be cheaper just to get 2-4 of the 350W Meanwell supplies, the higher current supplies I'm finding are pretty expensive:
SE-1500-27, Mean Well SE-1500-27
RSP-1000-27, Mean Well RSP-1000-27
SP-750-27, Mean Well SP-750-27
SE-6000-27, Mean Well SE-600-27
I don't anticipate running this thing full bore, I just want headroom so that music with lots of dynamic range sounds good. If I turned all the speakers on in the house full blast, I would probably run outside because it would be too loud.
4. Does the fact that they are out of stock mean they are changing them somehow? What should I know about what they are changing, if anyone knows?
Thanks!
I ordered a board as well. I'm interested in knowing if anybody has any info on when will they ship.
One more question to add:
Most of these power supplies I see have an input voltage range of 90-132V.
It's a long story, but our power company insists on giving us 'extra' voltage. I have measured the line voltage as high as 149V here, or as low as 134V. What precautions if any would I need to take, given that ugly situation?
Most of these power supplies I see have an input voltage range of 90-132V.
It's a long story, but our power company insists on giving us 'extra' voltage. I have measured the line voltage as high as 149V here, or as low as 134V. What precautions if any would I need to take, given that ugly situation?
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