Hi Daniboun,
Have you ever tested this particular amp to see how much power it can put out or does it stop at 48v (or whaever the internal DC PSU is)?
Have you ever tested this particular amp to see how much power it can put out or does it stop at 48v (or whaever the internal DC PSU is)?
Should Work with a 48v PSU as per spec but I did not test it.
I personnally use a 40v linear PSU and sounds awesome. The opa1622 help to open the soundstage.
Thanks for the link, mine from 3e was shipped today...too bad I didn’t get that info earlier.
Very good price also. From what I read many times the IcePower sounds better but looking forward to see how the 3255 sounds like.
Very good price also. From what I read many times the IcePower sounds better but looking forward to see how the 3255 sounds like.
My subjective opinion of my TPA3255 implementation is that it’s right up there with some of my best amps - even some Class A designs. But not all implementations of TPA3255 are second harmonic distortion dominant - most are third order and that may have a harsh sound for some.
xkr971 & Vacuphile...
I read your last posts...
And see no reason for you to (apparently) disagree with what the other one is saying, because...
At the end of the day, you are saying the same thing!!!!🙂
xkr: a fully driven TPA3255 in BTL mode shall output a signal about 90-95Vpp (sinewave 1kHz etc...): this is correct, as you scope shows it (of course, that's a measurement)...
BUT
your scope doesn't show anything different than what vacuphile says...
The thing to capture here is:
On the positive semi-cycle of the sinewave, one output node is driven by the TPA at +48V (say) close to saturation, while the other output node is at the same time driven to zero volt (ground): these are the 48V from vacuphile explanation...
Then on the negative semi-cycle, the first output node now reaches zero Vold (ground) while the second output node goes to +48v....
As it can easily be understood (I hope):
1/-The scope shows 96Vpp because it shows the differential voltage between the two output nodes, it is NOT showing a voltage w.r.t. ground...
2/-Maximum voltage from any output node w.r.t. ground never exceeds +48V (and I didn't say +/-48 but actually +48V) as vacuphile points at.
So both of you are right..🙂🙂🙂
I read your last posts...
And see no reason for you to (apparently) disagree with what the other one is saying, because...
At the end of the day, you are saying the same thing!!!!🙂
xkr: a fully driven TPA3255 in BTL mode shall output a signal about 90-95Vpp (sinewave 1kHz etc...): this is correct, as you scope shows it (of course, that's a measurement)...
BUT
your scope doesn't show anything different than what vacuphile says...
The thing to capture here is:
On the positive semi-cycle of the sinewave, one output node is driven by the TPA at +48V (say) close to saturation, while the other output node is at the same time driven to zero volt (ground): these are the 48V from vacuphile explanation...
Then on the negative semi-cycle, the first output node now reaches zero Vold (ground) while the second output node goes to +48v....
As it can easily be understood (I hope):
1/-The scope shows 96Vpp because it shows the differential voltage between the two output nodes, it is NOT showing a voltage w.r.t. ground...
2/-Maximum voltage from any output node w.r.t. ground never exceeds +48V (and I didn't say +/-48 but actually +48V) as vacuphile points at.
So both of you are right..🙂🙂🙂
Hi Kalamin,
I might be wrong, but I think Vacuphile has always been saying that you can’t get 96Vpp. I never claimed to try to measure them relative to GND. I have read his earlier posts on my thread and he was saying how it violates physics and that you can’t get more voltage than your supply. Maybe at DC levels you can’t, but this is AC and floating. What I am talking about is how much voltage can the amp put on the load. We all know with BTL amps, you cannot ground one of the outputs. What I am saying is that the blue board TPA3255 from eBay/AliExpress cannot even make more than 48vpp in differential BTL output mode - not referenced to GND. That’s a problem.
I might be wrong, but I think Vacuphile has always been saying that you can’t get 96Vpp. I never claimed to try to measure them relative to GND. I have read his earlier posts on my thread and he was saying how it violates physics and that you can’t get more voltage than your supply. Maybe at DC levels you can’t, but this is AC and floating. What I am talking about is how much voltage can the amp put on the load. We all know with BTL amps, you cannot ground one of the outputs. What I am saying is that the blue board TPA3255 from eBay/AliExpress cannot even make more than 48vpp in differential BTL output mode - not referenced to GND. That’s a problem.
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I did, there are no such results of anyone comparing them other than guessing.
In searching for a new Class D projects I’ve browsed for about 1 month all over the web and read tons of reviews, unfortunately I didn’t bookmark these links (I didn’t see the need for it)
IIRC, the TPA3255 was being evaluated against top of the line IcePower.
IIRC, the TPA3255 was being evaluated against top of the line IcePower.
daniboun,
Can you please share your source for the OPA1622 op amp on the DIP 8 package?
I don't know which Icepower is referred to here. I have 50asx2 and preferred TPA3255EVM on the rather high sensitivity speakers I used at the time (meaning max power was not a problem at all).
Edit: I see it was some top of the line of which I don't know anything.
for reliable operation and also getting the most out of the 3255EVM, which should I choose 36V or 48V power supply?
!
thank you both. I decided to buy a switching mode mean well 500 watt 36V power supply. I might end up using this on my open baffle speakers and i wanty to make sure that it can drive two 8 ohm woofers that are wired in parallel or in fact any other commercial subwoofer so its better to be safe with 4 ohm operation.
I dont know if this decision was smart as far as reliability of operation is concerned, but from previous experience I judged the fan on these mean well Switch modes to be loud so had to make sure to get a fan free model, thats why i had to rule out many 600 watt models and other 500 watt models that had fans and get a model without fans. hopefully it was the right decision. i know i cant have my amplifier in my living room with loud fan, just out of the question. I did see some models that i think you can turn ther fan on or off but I just decided to go with one that is fanless. any thoughts on that? i got this model:
Now i need to figure out how to configure the amp to run in balanced mode with XLR inputs. I read the manual and it does say that the default mode is BTL but it doesn't show the exact wiring required to circumvent the RCA inputs and use XLR connectors.
I dont know if this decision was smart as far as reliability of operation is concerned, but from previous experience I judged the fan on these mean well Switch modes to be loud so had to make sure to get a fan free model, thats why i had to rule out many 600 watt models and other 500 watt models that had fans and get a model without fans. hopefully it was the right decision. i know i cant have my amplifier in my living room with loud fan, just out of the question. I did see some models that i think you can turn ther fan on or off but I just decided to go with one that is fanless. any thoughts on that? i got this model:
An externally hosted image should be here but it was not working when we last tested it.
Now i need to figure out how to configure the amp to run in balanced mode with XLR inputs. I read the manual and it does say that the default mode is BTL but it doesn't show the exact wiring required to circumvent the RCA inputs and use XLR connectors.
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Connect to J10 and J12 headers (with J4 and J19 configured for "DIFF") as I mentioned here -
https://www.diyaudio.com/forums/class-d/314834-ti-tpa3255evm-86.html#post5728689