It can't hurt but you should not expect any miracles from it. If it is to solve problems you will probably discover this wasn't the solution.
Extension shaft kits are not that expensive... Some nice parts at the bottom of this page:
potentiometers, switches and attenuators homepage
Extension shaft kits are not that expensive... Some nice parts at the bottom of this page:
potentiometers, switches and attenuators homepage
My experience with these boards is rather different. I purchased mine from Parts Express. The price is a little higher, but the boards work on arrival and keep on working. I suspect that Sure provides a better product to Parts Express than they ship direct.
If changing the output filter network of any class D amplifier, it is somewhat important to use inductors and capacitors of the proper type (usually composite core toroid, wound with appropriate number of turns of 16 ga. solid wire) and high quality non-polar electrolytics at the very least. This is a tricky business on surface mount products like the Sure boards. The TK2050 board filters are designed for 4 ohms output impedance. If driving > 4 ohms, there will be changes (small, but possibly noticeable to golden eared listeners) in the frequency response curve at higher frequencies, in addition to decreased output power. This design as implemented by Sure is stable at 8 ohms, but I would be very cautious trying to use this at any greater impedance.
If changing the output filter network of any class D amplifier, it is somewhat important to use inductors and capacitors of the proper type (usually composite core toroid, wound with appropriate number of turns of 16 ga. solid wire) and high quality non-polar electrolytics at the very least. This is a tricky business on surface mount products like the Sure boards. The TK2050 board filters are designed for 4 ohms output impedance. If driving > 4 ohms, there will be changes (small, but possibly noticeable to golden eared listeners) in the frequency response curve at higher frequencies, in addition to decreased output power. This design as implemented by Sure is stable at 8 ohms, but I would be very cautious trying to use this at any greater impedance.
PS The first reports are in on the new TI and IR based boards, and these seem to have similar quality of sound to the earlier Tripath designs.
I strongly suspect that Tripath devices will be available indefinitely. The designs were sold to another semiconductor company, which could license them to anyone with a fab. Also, since a lot of these products are from China (pretty lax about intellectual property), I suspect that some of the chips being supplied are 'knock offs', although they seem to work as well as the originals, if that is so.
I have heard that even though some of TDA 749X boards have less than ideal output response due to some trickiness in designing output filters for these chips, the boards still sound good.
The higher power chips from IR and TI do require relatively high voltage power supplies, which, even in SMPS form, typically cost 1-3 X the cost of the amplifier board. Still a bargain, at about $300-350 for 500-600 clean watts. However, not for beginners--these power supplies and amp boards can easily fry both the experimenter and his/her attached transducers!
I strongly suspect that Tripath devices will be available indefinitely. The designs were sold to another semiconductor company, which could license them to anyone with a fab. Also, since a lot of these products are from China (pretty lax about intellectual property), I suspect that some of the chips being supplied are 'knock offs', although they seem to work as well as the originals, if that is so.
I have heard that even though some of TDA 749X boards have less than ideal output response due to some trickiness in designing output filters for these chips, the boards still sound good.
The higher power chips from IR and TI do require relatively high voltage power supplies, which, even in SMPS form, typically cost 1-3 X the cost of the amplifier board. Still a bargain, at about $300-350 for 500-600 clean watts. However, not for beginners--these power supplies and amp boards can easily fry both the experimenter and his/her attached transducers!
Hi all Tripath enthusiasts
to make a long story short, I use the TK2050 from sure and spent a long time improving it are at least trying.
I use a 30V SMPS to power it and out of curiosity, I connected a scope at the speaker output. I have a huge overshoot with several bounces, the highest peak is over 4V above the 30V power supply voltage.
I noticed that TRIPATH application provisions a snubber right before the two main filter inductors. Sure did not provision this space on the layout. The two inductors are directly connected to the TP2050 without snubber. I tried to add the recommended one (20 Ohm + 330 pF) and noticed a huge increase it heat (both on heatsink and inductors) confirmed by the current measure with no modulation : before adding the snubber, 270 mA; after adding it 380 mA
The overshoot is sligthly improved, still many bounces, but amplitude decreased by 2. This extra heating seems abnormal to me.
The only change to the original Sure board is the output inductors : I changed them to some 7A WURTH, still surface mount
The most important measurement is this the frequency of this overshoot : the bad square wave with overshoot is around 700 KHz, but the overshoot seems to be around 4 MHz (plus or minus a few hundred KHz, my scope is old and the trace a bit fuzzy !)
Did you guys already monitor the output ?
Do you see a quite good square wave, or do you have overshoots ?
Do I have this because this is my WURTH coils resonance frequency interfering ? Or is it a PCB layout problem from SURE ?
Any idea is welcome
thanks
to make a long story short, I use the TK2050 from sure and spent a long time improving it are at least trying.
I use a 30V SMPS to power it and out of curiosity, I connected a scope at the speaker output. I have a huge overshoot with several bounces, the highest peak is over 4V above the 30V power supply voltage.
I noticed that TRIPATH application provisions a snubber right before the two main filter inductors. Sure did not provision this space on the layout. The two inductors are directly connected to the TP2050 without snubber. I tried to add the recommended one (20 Ohm + 330 pF) and noticed a huge increase it heat (both on heatsink and inductors) confirmed by the current measure with no modulation : before adding the snubber, 270 mA; after adding it 380 mA
The overshoot is sligthly improved, still many bounces, but amplitude decreased by 2. This extra heating seems abnormal to me.
The only change to the original Sure board is the output inductors : I changed them to some 7A WURTH, still surface mount
The most important measurement is this the frequency of this overshoot : the bad square wave with overshoot is around 700 KHz, but the overshoot seems to be around 4 MHz (plus or minus a few hundred KHz, my scope is old and the trace a bit fuzzy !)
Did you guys already monitor the output ?
Do you see a quite good square wave, or do you have overshoots ?
Do I have this because this is my WURTH coils resonance frequency interfering ? Or is it a PCB layout problem from SURE ?
Any idea is welcome
thanks
TDA7498
So i didn't want to read the whole thread since its quite long, but i just bought this 4x100w amp from sure electronics based on the TDA7498 tripath chip, and i've tested it with a 24v dc HP-laptop power suply, and so far it sounds great, but it lags a bit on the kick and bass when the volume goes up, the reason for that ofcause, is that it needs more voltage. Anyways, i read in another thread, that the TDA7498 chip, is a kinda discount tripath chip compared to other chips, but since i havent heard any of the chips dicussed in the other thread i cant tell weather its discount or not, and if so, where i should by my next tripath amp, for future projects? (i'm going to build a festival audiosystem, where i am using the sure amp.)
link to the other thread http://www.diyaudio.com/forums/clas...tests-hifimediy-t2-ljm-l20d-sure-tda7498.html
So i didn't want to read the whole thread since its quite long, but i just bought this 4x100w amp from sure electronics based on the TDA7498 tripath chip, and i've tested it with a 24v dc HP-laptop power suply, and so far it sounds great, but it lags a bit on the kick and bass when the volume goes up, the reason for that ofcause, is that it needs more voltage. Anyways, i read in another thread, that the TDA7498 chip, is a kinda discount tripath chip compared to other chips, but since i havent heard any of the chips dicussed in the other thread i cant tell weather its discount or not, and if so, where i should by my next tripath amp, for future projects? (i'm going to build a festival audiosystem, where i am using the sure amp.)
link to the other thread http://www.diyaudio.com/forums/clas...tests-hifimediy-t2-ljm-l20d-sure-tda7498.html
But will it overheat or blow up? I read back a few pages and it seems like 27v is about the reasonable limits.......? This is for a portable setup.
Yep, the tripath version. I've seen the tripath datasheet saying 40v max. But I'm curious what the current thoughts are about power supply voltage in real world applications.
If I put 3 x 12v batteries on it and run it hard into a portable PA system for several hours, will it burn up....?
Thanks! But that apply's to the TDA7498 amp you have....which is not an actual tripath chip...?
AA-AB32186
This thread seems to have become inactive since Sept 2012. I bought the new AA-AB32186 board but doesn't seem there are many discussions out there for this version. My experience with it was it appeared Sure didn't QC it in factory. DC offset was high and I had to adjust it. I modded the tank caps and input caps and a zobel network (added in the wrong place still, after the coils). But I'd like to drill more into the output filter. Anyone using this version of board ? Any sharing ?
-AC
This thread seems to have become inactive since Sept 2012. I bought the new AA-AB32186 board but doesn't seem there are many discussions out there for this version. My experience with it was it appeared Sure didn't QC it in factory. DC offset was high and I had to adjust it. I modded the tank caps and input caps and a zobel network (added in the wrong place still, after the coils). But I'd like to drill more into the output filter. Anyone using this version of board ? Any sharing ?
-AC
I think the reason you don't see a lot of discussion on this Tripath stuff anymore is that these products are proven and are quite stable. Also, the Tripath is out of production as I understand it. Also, I am not certain they compare to the ICE or Hypex, however. Also, many people are looking for higher power - like 150-250W at 8 Ohms.
The usual suspects (Sure, ebay...) definitely don't compare to Hypex or ICE, it's a shame so little designers have bothered to make decent amplifiers out of them, which sure as .... is very well possible. In fact, some of the finest amplifiers ever made have Tripath technology in them.
Yes, the simplest way is to locate the input gain resistors. The input circuitry most likely resembles the datasheet application circuit for 99%, so I recommend to google on TK2050 datasheet, or even better EB-TK2050 or RB-TK2050....
Usually these resistors are 20K/20K per channel. That is Rin and Rfbk, each channel will have such a pair. Basically they set the gain and sensitivity of the internal opamps. You can lower that by using for instance 47K Rin and 20K Rfbk...
Lord knows there seem to be an almost endless supply of chips out there even if cloned. One would think that a little more development would have happened. Given the trend for the headphone crowd to go with balanced cabling I am surprised no 2024 headphone amps have surfaced. I have used one of the Lepai units to run a set of orthodynamic drivers and the result was almost a magical experience the clarity was breathtaking.
With regard to output power, is the 2050 not a chainable design?
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