Yep, the cap is from the recommendation at the 41Hz site. Also, I bypassed it with a .1uF because someone suggested that would be a good idea as well.
I'm not technically strong, but I can follow the directions of those that are.
I owe much to the many that are generous with their knowledge. Now, if I were only wealthy enough to act on that...
I'm not technically strong, but I can follow the directions of those that are.
I owe much to the many that are generous with their knowledge. Now, if I were only wealthy enough to act on that...Here's a link to the voltmeter site:
http://www.classicinstruments.com/
Also, Eastwood auto parts has a nice version. Have fun,
http://www.classicinstruments.com/
Also, Eastwood auto parts has a nice version. Have fun,
i have 2 AMP1 boards and 1 AMP2 board (300watt) on its way, ill certainly give some input once everythings running. will be interesting to compare the 2.
for the record.. the AMP1 (tA2022) boards ar eexact copies of tripath evaluation boards
AMP3 boards ( TP2350B chipset ) are slightly different to reference.
cheers
Jimmt
for the record.. the AMP1 (tA2022) boards ar eexact copies of tripath evaluation boards
AMP3 boards ( TP2350B chipset ) are slightly different to reference.
cheers
Jimmt
Nice job!
Ohenry,
Nice professional looking unit. What does the meter read out? I would guess the state of the battery would make the most sense.
I did my own little SI mod using a small SMPS with a large buffer cap (22,000uf) and am very pleased with the results. All electronics has several suitable 12V units, cheap. Most are adjustable or easily changed to be. Regulated 13.5 volts and no hassle with recharging, worth considering. My unit now has a home at my computer and it continually surprises me with its quality sound. Also surprising how reliable it is as my grandson is constantly changing things around and not turning it off first. (Great worst case test site!)
Thanks for the link to the case. These are nice units.
Roger
Ohenry,
Nice professional looking unit. What does the meter read out? I would guess the state of the battery would make the most sense.
I did my own little SI mod using a small SMPS with a large buffer cap (22,000uf) and am very pleased with the results. All electronics has several suitable 12V units, cheap. Most are adjustable or easily changed to be. Regulated 13.5 volts and no hassle with recharging, worth considering. My unit now has a home at my computer and it continually surprises me with its quality sound. Also surprising how reliable it is as my grandson is constantly changing things around and not turning it off first. (Great worst case test site!)
Thanks for the link to the case. These are nice units.
Roger
Re: Nice job!
Yes, it's for the battery voltage. Actually, a waste of money when using a 7.5Ah battery as it takes many hours to significantly drain (>8 hrs is the longest I've run it and it still read slightly <12 volts). It does look cool though.
After 100 hours, the amp has matured nicely and has gotten very smooth and refined sounding.
I just received two pairs of NOS OIP caps in the mail to shuffle with the next amp3 build. It'll be interesting to see how the old and new play together.
sx881663 said:
Yes, it's for the battery voltage. Actually, a waste of money when using a 7.5Ah battery as it takes many hours to significantly drain (>8 hrs is the longest I've run it and it still read slightly <12 volts). It does look cool though.
After 100 hours, the amp has matured nicely and has gotten very smooth and refined sounding.
I just received two pairs of NOS OIP caps in the mail to shuffle with the next amp3 build. It'll be interesting to see how the old and new play together.
coolkhoa said:ohenry,
Where did you get those binding posts and RCA jacks? Thanks.
P.S. Very nicely done!
Thanks, the binding posts are some WBT's that I picked up reasonably a while back from a guy that didn't need them. The RCA's are just the Dayton brand from Parts Express. The case front and back panels are so thick, some jacks are too short to work.
I'm still enjoying the amp3 very much after a few weeks. This one's a keeper. Now it's time to build a mule to test out some signal caps.
I have my amp1 board done and hooked up to Proac 2.5 clones in proto testing..
what can i say , mm wow?
, when below mentioned issues aren't happening.. awesome detail transient response, smoothness, quietness+++ , this thing compares to my monoblock ESp101A amp, im almost disapointed to think i may be replacing it with a bi amp set of these now.
listening to fiona apple lastnight, the midrange was so smooth, almost valve like, never any harshness as the esp amp sometimes can be, totally not what one thinks of when they hear the word class D.
as for the problems, im going to post this on 41hz aswell , and see how it goes after some more use, when I first fired it up and put it to work detail and clarity was there, but soundstage seemed repressed, lack of imaging, almost like poor stereo seperation. but more worrying transient response to drums was shocking, it may have been some of the new caps im not sure. specially some of the smaller electros, I want to rid any cheap electros from the signal part anyway. also sub 50hz or so bass was severely lacking ,/ was weak.
However after several hours of high powered use the symptoms completly disapeared I came back into the room at one stage and everything had come alive, deep soundstage, room filling dynamic sound. and transients were normal. this morning everything seems in order still, but its getting hard to tell now. i need to back to back with the ESP again.
anyway if anyones had similar experiences , is there also a possibilty of performance changing after the LP filters warm up, i would have expected oposite behaviour as the DCR increased. but im not entirely familiar with the operation of the LP filter at the moment, nor know how it will react with the load.
last but not least.. has anyone tried viewing the output ona scope ?? , i had absolutly no luck, couldnt get sync from all the VHF noise , not evne whenn syncing off the input!
anyway hopefully i can sort all these issues on a perma basis , and refine things a bit more, ill be one happy camper
what can i say , mm wow?
, when below mentioned issues aren't happening.. awesome detail transient response, smoothness, quietness+++ , this thing compares to my monoblock ESp101A amp, im almost disapointed to think i may be replacing it with a bi amp set of these now. listening to fiona apple lastnight, the midrange was so smooth, almost valve like, never any harshness as the esp amp sometimes can be, totally not what one thinks of when they hear the word class D.
as for the problems, im going to post this on 41hz aswell , and see how it goes after some more use, when I first fired it up and put it to work detail and clarity was there, but soundstage seemed repressed, lack of imaging, almost like poor stereo seperation. but more worrying transient response to drums was shocking, it may have been some of the new caps im not sure. specially some of the smaller electros, I want to rid any cheap electros from the signal part anyway. also sub 50hz or so bass was severely lacking ,/ was weak.
However after several hours of high powered use the symptoms completly disapeared I came back into the room at one stage and everything had come alive, deep soundstage, room filling dynamic sound. and transients were normal. this morning everything seems in order still, but its getting hard to tell now. i need to back to back with the ESP again.
anyway if anyones had similar experiences , is there also a possibilty of performance changing after the LP filters warm up, i would have expected oposite behaviour as the DCR increased. but im not entirely familiar with the operation of the LP filter at the moment, nor know how it will react with the load.
last but not least.. has anyone tried viewing the output ona scope ?? , i had absolutly no luck, couldnt get sync from all the VHF noise , not evne whenn syncing off the input!
anyway hopefully i can sort all these issues on a perma basis , and refine things a bit more, ill be one happy camper
Sorry mr pushpull, my first classD exp here.
sx881663, i hope so, it seems to be quite good now. im still not convinced that its performance isnt improving once run for some time , so im still going to look into this , maybe im having some ringing , measuring with the cro is virtually useless , i managed to get a waveform up, with all the carrier noise sitting on top, im going to have to set up an lp filter for it
sx881663, i hope so, it seems to be quite good now. im still not convinced that its performance isnt improving once run for some time , so im still going to look into this , maybe im having some ringing , measuring with the cro is virtually useless , i managed to get a waveform up, with all the carrier noise sitting on top, im going to have to set up an lp filter for it
Trouble shooting
mAJORD
Seems most of the time when tracking down noise you are actually looking at contaminated ground signals. If you had a good broad band current probe it would help a lot, try borrowing one. If not you might try a small high freq. transformer to isolate the grounds from the scope. You can make one with several bifilar turns through a toroid core. It should be made from the right kind of material to work very well though.
If you do this you should be able to see the same signal as the actual part using it is. Connect the transformer input through a resistor and cap so it doesn’t mess up the signal you are trying to measure. A little experimenting will get you there. Don’t expect flat response from the transformer but it should be a lot better than not seeing anything at all. As Bruno and others have stated Zobel networks will do wonders for ringing if done properly.
Let us know what you find and good luck!
Roger
mAJORD
Seems most of the time when tracking down noise you are actually looking at contaminated ground signals. If you had a good broad band current probe it would help a lot, try borrowing one. If not you might try a small high freq. transformer to isolate the grounds from the scope. You can make one with several bifilar turns through a toroid core. It should be made from the right kind of material to work very well though.
If you do this you should be able to see the same signal as the actual part using it is. Connect the transformer input through a resistor and cap so it doesn’t mess up the signal you are trying to measure. A little experimenting will get you there. Don’t expect flat response from the transformer but it should be a lot better than not seeing anything at all. As Bruno and others have stated Zobel networks will do wonders for ringing if done properly.
Let us know what you find and good luck!
Roger
mAJORD,
I have recently built a PC amp with the AMP1 kits, and I must say I'm impressed for the price. My setup is tangband 3 1/2 inch fullrange using W3-871S and John Zaph's design for the monitor speakers, and a 8" peerless woofer in a small sealed cabinet as the subwoofer. For the full range speakers I use one AMP1 with a high pass active filter (90hz). For the subwoofer a low pass filter and a linkwitz transform to equalise the subwoofer response to force the bass at the lower frequences, and using another AMP1 in bridged mode.
The AMP1 took about 20 hours of listening before it settled down, at first treble was shrill/brittle but after time it settled down. I have also bypassed the electro input caps with MKP caps and it improves the treble further. The sound is now open, huge soundstage and able to resolve instruments much better than my previous MOSFET amp. Some attention to the power supply is needed, I use separate rectifiers & filter caps for the monitor amp1 and the subwoofer amp1, and have paralleled 8 x Panasonic FC 2,200uF caps per supply and separate supply for the active filters.
Do remember when bypassing the input caps on these boards that the Tripath chip has a 2.5v bias so you MUST use a capacitor in the input.
Unfortunately the first AMP1 has developed an intermittent fault where the right channel outputs an unsymettrical signal that shuts the amp down, probably because of a fault in my soldering (not the quality of the board which is very high), so I have ordered another AMP1 to replace it. These kits are good value for what you get so I dont mind purchasing another.
Regards,
Dean
I have recently built a PC amp with the AMP1 kits, and I must say I'm impressed for the price. My setup is tangband 3 1/2 inch fullrange using W3-871S and John Zaph's design for the monitor speakers, and a 8" peerless woofer in a small sealed cabinet as the subwoofer. For the full range speakers I use one AMP1 with a high pass active filter (90hz). For the subwoofer a low pass filter and a linkwitz transform to equalise the subwoofer response to force the bass at the lower frequences, and using another AMP1 in bridged mode.
The AMP1 took about 20 hours of listening before it settled down, at first treble was shrill/brittle but after time it settled down. I have also bypassed the electro input caps with MKP caps and it improves the treble further. The sound is now open, huge soundstage and able to resolve instruments much better than my previous MOSFET amp. Some attention to the power supply is needed, I use separate rectifiers & filter caps for the monitor amp1 and the subwoofer amp1, and have paralleled 8 x Panasonic FC 2,200uF caps per supply and separate supply for the active filters.
Do remember when bypassing the input caps on these boards that the Tripath chip has a 2.5v bias so you MUST use a capacitor in the input.
Unfortunately the first AMP1 has developed an intermittent fault where the right channel outputs an unsymettrical signal that shuts the amp down, probably because of a fault in my soldering (not the quality of the board which is very high), so I have ordered another AMP1 to replace it. These kits are good value for what you get so I dont mind purchasing another.
Regards,
Dean
im gonna give that a go ss, dont have any access to the probe so ill make the tranny up, sounds like the go.
deandob, your psu sounds very similar to my final design, at the moment im using el cheapo caps parralelled, but yes the final will be 8 2200uf aswell, low esr. definatly going to bypas those caps when I can.
cheers
deandob, your psu sounds very similar to my final design, at the moment im using el cheapo caps parralelled, but yes the final will be 8 2200uf aswell, low esr. definatly going to bypas those caps when I can.
cheers
Majord,
Please post your results after 50 or so hours of burn in. I didn't believe in burn in for digital amps, but both my Panasonic XR-45 and this new Tripath amp have noticeable grain in the sound when new which then mellows.
I'm waiting for the new AMP1 before completing this amp. Next project is 5 x UCD amps for my home theatre
Regards,
Dean
Please post your results after 50 or so hours of burn in. I didn't believe in burn in for digital amps, but both my Panasonic XR-45 and this new Tripath amp have noticeable grain in the sound when new which then mellows.
I'm waiting for the new AMP1 before completing this amp. Next project is 5 x UCD amps for my home theatre
Regards,
Dean
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