That's funny, a TEG (thermoelectric generator) on one side of the heatsink, that feeds a TEC (thermoelectric cooler) on the opposite side of the heatsink.
With a fan needed on both the TEG and TEC, it's sure to be a hot success. Oh, don't forget to power the fans with the TEG.
With a fan needed on both the TEG and TEC, it's sure to be a hot success. Oh, don't forget to power the fans with the TEG.
Hi
Are actually some ideas to get the heat back (Seebeck Effekt) from the overheat of an class A or A/B Amp..?
sorry it souids strange/stupid... but.....
Thermogeneratoren
Hi
Do you have experience in performance /sound for special good caps for class D? e.g. Elna Silmic II or the Nichicons "Muse" serie (UKZ or UFG).......
I am close to buy one myself. At least it will give me some basis for disturbing in the discussions about how much better it is than the other class D chips
This fine FXC502S Pro or a sepcial board, e.g. because
Which do you want to buy, i looked exactly at this board
MINI HIFI TPA3255 300W + 300W Class D audio Digital Amplifier Board DC50V -in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group
They might have chosen a 10uF ceramic smd cap because the value is big enough it might offset whatever sonic artifacts a ceramic this size possesses? Maybe a through hole regular film cap can be smaller?
My wife has better ears than me, she's just not using them. I have better eyesight, but she is better at finding mushrooms in the forest. We are probably trying to compensate for our lesser senses.
If she says the TPA3250 is better than the TPA3116, without me asking about it, then i'm happy I was not under some form of bias.
My wife has better ears than me, she's just not using them. I have better eyesight, but she is better at finding mushrooms in the forest. We are probably trying to compensate for our lesser senses.
If she says the TPA3250 is better than the TPA3116, without me asking about it, then i'm happy I was not under some form of bias.
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somthing like that !! sorry for german web page...
Energy Harvesting: EnOcean: Warme als Stromquelle | Markt&Technik
search for Thermo Spintronik
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I know better audio electrolytic capacitors exist, and I have some in my lab, but I cannot say how much better they are.
My candidate board is this:
MINI HIFI TPA3255 300W + 300W Class D audio Digital Amplifier Board DC50V -in Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group
,which should be exactly what you suggest.
Do I need it? - no. Do I want it? - yes. As a Dutch girl I knew once said: "The only difference between boys and men is the price of their toys".
Depends by 95% of the the man at the fretboard
by the way: I would bet a strat played through my TPA3118 stage amp can sound nice as well
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In reply to questions about class D crossover distortion:
This is governed by selection of switching frequency and output inductor value. A proper 250W/8r class D amplifier can have as much as 50W of class A before crossover distortion arises. Proper dead time results in no substantial increase in THD past this power level and until 3dB below clipping.
In quality class D (AD modulation) crossover distortion is not a single dead band around 0A current output (like class B or AB), it is 2 dead bands around "+i" and "-i" amperes output current, where "i" is the amplitude of the current sawtooth biasing output inductor (it can be calculated from +V/-V rails and output inductor value, i=(V/L)*0.25/fsw, for a 22uH inductor, 50V and 250khz: i~=2.3A, about 20W/8r of class A).
Hi-Fi class D shall not be mistaken with boombox class D.
This is governed by selection of switching frequency and output inductor value. A proper 250W/8r class D amplifier can have as much as 50W of class A before crossover distortion arises. Proper dead time results in no substantial increase in THD past this power level and until 3dB below clipping.
In quality class D (AD modulation) crossover distortion is not a single dead band around 0A current output (like class B or AB), it is 2 dead bands around "+i" and "-i" amperes output current, where "i" is the amplitude of the current sawtooth biasing output inductor (it can be calculated from +V/-V rails and output inductor value, i=(V/L)*0.25/fsw, for a 22uH inductor, 50V and 250khz: i~=2.3A, about 20W/8r of class A).
Hi-Fi class D shall not be mistaken with boombox class D.
A post-filter feedback self-oscillating modulator with single integrator can achieve under 0.01ohm output impedance across the audio band. This is a damping factor of about 1000 up to 20khz.
For these modulators, cross-talk intermodulation is mitigated by trimming all channels to oscillate at same frequency when idle. With 2 PCB construction (modulator+power) 100dB channel separation across the audio band is attainable.
Of course there are simpler ways to do class D, but performance suffers.
Here is a photo of my new Dx amp running on two 19v SMPS bricks for dual rail:
You are using the famous unbranded 8$ "Digital to Analog converter" as a DAC?
One aspect, cooling.
High power! Efficiency of TDA8954 around 90%. Efficiency of class AB around 70%.
Cooling 35W off a TDA8954 (HSOP24 SMD housing) is somewhat more difficult than some (2x)100W distributed on 12 TO-264 housings.
So, unless you have the DBS23P housing for your TDA8954, I would take that into account.
High power! Efficiency of TDA8954 around 90%. Efficiency of class AB around 70%.
Cooling 35W off a TDA8954 (HSOP24 SMD housing) is somewhat more difficult than some (2x)100W distributed on 12 TO-264 housings.
So, unless you have the DBS23P housing for your TDA8954, I would take that into account.
In practical use, it's even a worse difference than that. Those figures are at full sinewave power, a point that is virtually never reached in a decently designed system. Average power to a speaker in most home stereo systems isn't even a single watt (!), and "average" is what counts for heat. The efficiency of class D at that power level (assuming an amp rated for higher power, say 50W or more) is very, very, much higher than a class AB amp.
I am fully agree with you
Every class D designed by different person has its own unique sound.
Even change inductor from different brand it may has different sound.
The point we cannot generalize all class D. But must be a specific product.
All I can give is my experience. I went from an expensive 7.1 pioneer surround reciever, with all Paradigm speakers, to a TPA3116 based class D with 2 Paradigm Titan V2 speakers and a powered Yamaha sub. When listening to music there is no comparison. The $75 Class D Kicks the $1000 surround amp for music quality all day.
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