Tom, thanks for coming here to answer questions.
What products do you have in the works? ie. SMPS, any more high power amps?
What's the idle power usage on the 1000W and 600W modules?
Are the modules suitable for connection directly to drivers (DC protection, is there a 'turn on delay')?
Are the modules designed to handle a thrashing? Looks like they might need additional heatsinking.
Is it possible to subscribe to your newsletter? I can only see an unsubscribe link on the website.
What products do you have in the works? ie. SMPS, any more high power amps?
What's the idle power usage on the 1000W and 600W modules?
Are the modules suitable for connection directly to drivers (DC protection, is there a 'turn on delay')?
Are the modules designed to handle a thrashing? Looks like they might need additional heatsinking.
Is it possible to subscribe to your newsletter? I can only see an unsubscribe link on the website.
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We have several products in the works. Right now, I'm trying to finish a switch mode power supply for the amps. We will have several different models, and all designed specifically for audio. The one we should have available soon is 600W with short term peaks to 1200W. All have PFC front end so they can be used all over the world with no problems. We are also working on a 4 channel amp, and of course a few other higher power amps... no details to offer on these now. All of our amps have DC protection. All amps except for the T.I. amps have a 1 second turn on delay. Yes... these amps are made to handle a thrashing. On some of the higher power models, it might be wise to add to the heat sink if it's going to be pushed hard for long periods of time. To subscribe to our newsletter, you just have to sign up on the website and it will give you the option to be added to the newsletter... our new updated website is almost finished and should be up within the week, and it does have a box on the bottom where you can sign up for the newsletter.Tom, thanks for coming here to answer questions.
What products do you have in the works? ie. SMPS, any more high power amps?
What's the idle power usage on the 1000W and 600W modules?
Are the modules suitable for connection directly to drivers (DC protection, is there a 'turn on delay')?
Are the modules designed to handle a thrashing? Looks like they might need additional heatsinking.
Is it possible to subscribe to your newsletter? I can only see an unsubscribe link on the website.
We're working on one very similar... don't know when we will have it ready... my hands are pretty full now, but I'll keep you posted!Please,please,please consider a 5 channel,balanced,200w/8ohm amp.
Mark Allen,
I am interested in these Class D amps with the TI chip. Thanks for trying one out and posting your impressions. One thing I have noticed with these chip style amps (be it steady-state or switching) is that they need some run time before they start to sound any good at all. Call it break-in if you dare. They are typically shrill and shallow with peaky response and flabby bass until they've got quite a few hours on them. Any changes there?
Can you please answer the following questions?
How is the bass? I'm considering one of these for low end duty in a biamp system.
Tom from ClassD stated above that the TI amps do not have a turn-on delay. Do you have any problems with noise when turning on or off? Their website specifies that there is click and pop suppression, so perhaps that's built into the chip.
You stated that the amp needed significant warm-up to sound its best. Have you tried simply leaving them on? Class D should make that economical, perhaps even sensible.
Have you tweaked any of the standard amp components?
Are you running the amp with balanced or single-ended input?
I have seen other posts regarding heat management requirements of the OPA1632 opamps. Any problems there?
Sorry for all the questions. I already contacted Tom at ClassD directcly, and he answered my commercial questions promptly, but it's nice to have a third party confirmation of these performance issues. This is a new company (at least, to me) with economical products that show great promise, and they're built in my country. I came upon them on eBay, and I know that some of the products offered there do not meet reasonable standards of performance. I don't want to spend money and time building an amp that can't keep its promises.
Peace,
Tom E
I am interested in these Class D amps with the TI chip. Thanks for trying one out and posting your impressions. One thing I have noticed with these chip style amps (be it steady-state or switching) is that they need some run time before they start to sound any good at all. Call it break-in if you dare. They are typically shrill and shallow with peaky response and flabby bass until they've got quite a few hours on them. Any changes there?
Can you please answer the following questions?
How is the bass? I'm considering one of these for low end duty in a biamp system.
Tom from ClassD stated above that the TI amps do not have a turn-on delay. Do you have any problems with noise when turning on or off? Their website specifies that there is click and pop suppression, so perhaps that's built into the chip.
You stated that the amp needed significant warm-up to sound its best. Have you tried simply leaving them on? Class D should make that economical, perhaps even sensible.
Have you tweaked any of the standard amp components?
Are you running the amp with balanced or single-ended input?
I have seen other posts regarding heat management requirements of the OPA1632 opamps. Any problems there?
Sorry for all the questions. I already contacted Tom at ClassD directcly, and he answered my commercial questions promptly, but it's nice to have a third party confirmation of these performance issues. This is a new company (at least, to me) with economical products that show great promise, and they're built in my country. I came upon them on eBay, and I know that some of the products offered there do not meet reasonable standards of performance. I don't want to spend money and time building an amp that can't keep its promises.
Peace,
Tom E
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I've got one channel of my PBTL 5630s going now so maybe I can comment.
So far bass sounds fine, but this is into a small two way without any 'real' bass (below 50hz).
Turning mine on and off produces nothing to worry about. One meter away from the loudspeaker I barely heard anything.
I've got a pair of OPA1632s inside an ADC that I built and I can say that they do get quite hot. That's running from +-11.6volts though, the TI evaluation boards and the amp from ClassD, run them from a single +12V rail so should run much cooler then in my ADC.
I'm building mine specifically to handle the bass bit of my open baffles, so when I get more of it up and running I'll let you know how it compares to the ~250W/4ohm class B amp I've got atm.
So far bass sounds fine, but this is into a small two way without any 'real' bass (below 50hz).
Turning mine on and off produces nothing to worry about. One meter away from the loudspeaker I barely heard anything.
I've got a pair of OPA1632s inside an ADC that I built and I can say that they do get quite hot. That's running from +-11.6volts though, the TI evaluation boards and the amp from ClassD, run them from a single +12V rail so should run much cooler then in my ADC.
I'm building mine specifically to handle the bass bit of my open baffles, so when I get more of it up and running I'll let you know how it compares to the ~250W/4ohm class B amp I've got atm.
Well that confirms it, I DID manage to destroy one of them -.-.
Somehow one of the outputs was destroyed and measures as a short from ground to the output. My guess is I managed to blow up one of the FETs (are they fets?) in the output stage. Oh well.
Adding to what I wrote above, they do make a very small noise when turned on and are very quiet in operation, hiss and hum etc.
Somehow one of the outputs was destroyed and measures as a short from ground to the output. My guess is I managed to blow up one of the FETs (are they fets?) in the output stage. Oh well.
Adding to what I wrote above, they do make a very small noise when turned on and are very quiet in operation, hiss and hum etc.
Well, MIne died the other day. I was watching the last installment of Die Hard and when Bruce Willis fired a gun off one channel of the amp departed for amp heaven. Tom thinks it was probably a defective chip and he is repairing it under warranty. I should have it back by mid next week.
On my Dynaudios the bottom end has great impact and no clicks and pops. In fact I had mine located right on top of one of the speakers. Running it off the switching supply shown in the earlier posts in this thread. Bass is deep and clean. High end is what takes a bit of warming up. The amp seems to smooth out after an hour or more.
Mark
On my Dynaudios the bottom end has great impact and no clicks and pops. In fact I had mine located right on top of one of the speakers. Running it off the switching supply shown in the earlier posts in this thread. Bass is deep and clean. High end is what takes a bit of warming up. The amp seems to smooth out after an hour or more.
Mark
When you look at the chip you do wonder about potential failure. The thing is literally tiny and when you consider how much current will pass through it the brain boggles a little.
I don't know how large the silicon area provided for each 'switcher' is, but it cannot be that much. In other words, if a normal power transistor/FET had a bad area on the die, perhaps its only 1/50th of the total area and it's never a problem. But that same defect could represent 1/5th of the area in the 5630 - boom.
I don't think my blown chip was defective I think I did something to it by accident.
Could it be possible, that instead of the chip going to silicon heaven that one of the solder joins between chip and board could have failed? I mean you're going to shove a huge amount of current through what is relatively a tiny little pin.
The chips are thoroughly protected against short circuit, over current and finding shorts/lack of power on the output stage. In PBTL mode if one of the four outputs registers a fault, the chip wont start up.
It could just be a bad chip, but I can't imagine the % of bad chips would be all that high and 'lucky' you if you got one
Hmmm, early failure does not bode well.
Let me get this straight. Fifth element, you have an amp of your own design that uses the TI chip that is used in the ClassD amp? Mounted on PCB or hard wired?
Mark, you have an amp from ClassD?
You were both using SMPS's? Do you have confidence in them?
Both failed, one perhaps by "accident" (care to elaborate?), one perhaps from chip failure, which I think is a standard manufacturer response, but probably unlikely.
What say you, Tom of ClassD?
Do (did) either of you run your amps with balanced input? Not that that would contribute to failure, but it would probably affect the sonics, which you both report to be decent.
Mark, I'm not sure I would ever put any type of equipment on top of a speaker for fear that vibration might cause problems. Perhaps that was a factor in the failure? It would certainly affect the sonics. Did you have the amp in an enclosure?
Peace,
Tom E
Let me get this straight. Fifth element, you have an amp of your own design that uses the TI chip that is used in the ClassD amp? Mounted on PCB or hard wired?
Mark, you have an amp from ClassD?
You were both using SMPS's? Do you have confidence in them?
Both failed, one perhaps by "accident" (care to elaborate?), one perhaps from chip failure, which I think is a standard manufacturer response, but probably unlikely.
What say you, Tom of ClassD?
Do (did) either of you run your amps with balanced input? Not that that would contribute to failure, but it would probably affect the sonics, which you both report to be decent.
Mark, I'm not sure I would ever put any type of equipment on top of a speaker for fear that vibration might cause problems. Perhaps that was a factor in the failure? It would certainly affect the sonics. Did you have the amp in an enclosure?
Peace,
Tom E
Well, there is not any vibration one can feel on top of my Dynaudios even at loud levels. The cabinets are pretty well made. I'm running in single ended input mode driving it with a home brew grounded grid. Tom says the SMPS was not a factor even thought is is capable of 13 amps continous and probably alot more than that peak. The chips have built in current limiting. He also builds these boards for the government and claims to have had basically zero failures. I probably will not place mine in a permanent enclosure until I have completely tested it out. Enclosures many times can cause more problems then they cure.
Mark
Mark
Yes.
Double sided, 2oz PCB. I've taken a few pictures, but someone ran off with the digital camera they were on
I'm using mine with a single ended input.
Opamp buffer followed by a 4th order highpass at 20hz, then another opamp inverts the signal for the -ve input.
I am going to mention a bad/loose connection again between one of the pins and its track on the PCB.
A solid connection is essential if the chip is to function anywhere near properly at high power levels.
If one of the pins had a dry joint between it and the track or say only a small amount of solder was connecting the pin to the track. Then when used the chip would be fine, except you turn it up and the dodgy connection can't cope and the solder melts breaking the connection. The amp turns off. When you try to power it back on it stays quiet because one of the outputs isn't powered on.
I had something similar happening with mine, it worked fine at low power levels, but when I tried to push it, it would suddenly turn off. Removing and reapplying power would get it to turn back on. I went through each of the pins with a magnifying glass and a soldering iron and found that a couple of the single pins weren't soldered down particularly well, so it just goes to show.
Maybe your chip didn't die, I guess ClassD will let you know anyhow. Unless they just replace the chip.
A solid connection is essential if the chip is to function anywhere near properly at high power levels.
If one of the pins had a dry joint between it and the track or say only a small amount of solder was connecting the pin to the track. Then when used the chip would be fine, except you turn it up and the dodgy connection can't cope and the solder melts breaking the connection. The amp turns off. When you try to power it back on it stays quiet because one of the outputs isn't powered on.
I had something similar happening with mine, it worked fine at low power levels, but when I tried to push it, it would suddenly turn off. Removing and reapplying power would get it to turn back on. I went through each of the pins with a magnifying glass and a soldering iron and found that a couple of the single pins weren't soldered down particularly well, so it just goes to show.
Maybe your chip didn't die, I guess ClassD will let you know anyhow. Unless they just replace the chip.
Got my board back today from Tom. There WAS definitely a problem with that last chip. I've had it running for several hours now and this board does not go through the warm up process the other one did before it sounds good. This sounds good the second you turn it on. It also seems to be running lots cooler as well. Anyway, a big thanks to Tom at Class D audio!! I don't think the board was gone more than 4 days including the ship time.
All I can say is that this is one of the finest amplifiers I've ever had the opportunity to listen to. I also have a Sure Electronics Tripath 2050 board and it doesn't begin to hold a candle to Tom's Class- D T.I. based board. I've also got a couple of Pass Labs clone amps and the Krell clones. I don't know if any mods would make the Class D board any better... perhaps but it's not going to be beaten even right out of the box!!
Mark
All I can say is that this is one of the finest amplifiers I've ever had the opportunity to listen to. I also have a Sure Electronics Tripath 2050 board and it doesn't begin to hold a candle to Tom's Class- D T.I. based board. I've also got a couple of Pass Labs clone amps and the Krell clones. I don't know if any mods would make the Class D board any better... perhaps but it's not going to be beaten even right out of the box!!
Mark
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Ok dumb question. If I have the amp board the will supply 300 watts per channel I would technically need a 660 watt power supply, right?
The reason I'm asking is I see class d sell a 1000 watt kit that has a power supply with a 400 va transformer.
I'm not going to use a switching power supply though. I have the parts to build a very large linear supply with a couple 150000 mfd filter caps. I figuared that should do the trick. The transformer are 1 kva with 2 13 vac secondaries. And I have 2 of them. There about 30 pounds a piece.
It won't be light though but I want it to power quite a few of these amps. Home theater and all with tri amped front speakers.
Nick
The reason I'm asking is I see class d sell a 1000 watt kit that has a power supply with a 400 va transformer.
I'm not going to use a switching power supply though. I have the parts to build a very large linear supply with a couple 150000 mfd filter caps. I figuared that should do the trick. The transformer are 1 kva with 2 13 vac secondaries. And I have 2 of them. There about 30 pounds a piece.
It won't be light though but I want it to power quite a few of these amps. Home theater and all with tri amped front speakers.
Nick
Well I know you can gain a little in the conversion to dc minus the loses in the diodes. Still don't get how they run a 1000 watt amp with a 400 va transformer.
But ya if I had the switching supply I would use it. Just figure since I had the parts for a linear supply I might as well use them, ya know.
Plus I like looking in and seeing the big capacitors LOL.
Nick
P.S. I only calculated for 90% efficiency the first time. Thats why I quoted the 660 watts.
But ya if I had the switching supply I would use it. Just figure since I had the parts for a linear supply I might as well use them, ya know.
Plus I like looking in and seeing the big capacitors LOL.
Nick
P.S. I only calculated for 90% efficiency the first time. Thats why I quoted the 660 watts.
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