Yes, I used 2 resistors for L/R, what I would like to know is if these resistors create problems by deteriorating the input signal. Does using even lower resistance values create quality, gain, and impedance issues?
There are no interference noises, it looks like typical ground noise. The noise is not in the busy line, that is perfect, but in the others. Now I'm trying to put the resistors directly to the input terminals of the free channels, then it will be better to have them in the selector board I have on the RCA inputs?
I don't know if we're talking past each other right now.
These open lines have no connection to your amplifier at all. A connection is only created when you switch the relay with the selection switch. Why are you bothered by that?
These open lines have no connection to your amplifier at all. A connection is only created when you switch the relay with the selection switch. Why are you bothered by that?
Yes that's right, I only worry if my wife accidentally moves the selector when the volume is high. I have not tested if there is noise with the CD player connected but turned off. I'll try later.
How and at what point do you regulate the volume?
The normal constellation is Switchable Inputs -> Volume Poti -> Active Small Signal Amplification -> Output to Amplifier.
Alternatively, you could simply pull the appropriate contacts from the ribbon cable out of the post connector so that these relays are not addressed. These individual contacts must of course be isolated and can be used again later.
The normal constellation is Switchable Inputs -> Volume Poti -> Active Small Signal Amplification -> Output to Amplifier.
Alternatively, you could simply pull the appropriate contacts from the ribbon cable out of the post connector so that these relays are not addressed. These individual contacts must of course be isolated and can be used again later.
You can limitate the number of inputs in Rotary Switch by changing washer stops, normally have from 2 position to 6 or twuelve depending models.
I'm using 1K resistors on all inputs, I think it's okay, the noise is acceptable, you still need to get close to the speakers to hear it.
If you don't use that input then you may go lower values (even 0 ohm) of course. But if you will use them later then in this case you will have a very low input impedance in these channels. So this will be a problem for the source..
Of course the best solution is "not to use" these channels as Roland968 mentioned..
Hey people,
after much reading, thinking it over, deceiding, discarding the decision, reading again, etc. I'm about to join your game. First is to get an appropriate gaming device. I was into the classical design which is seen at the beginning of this thread, but the newer version seems to have some real improvements, so I am about to order two of these > 2023 improved TPA3255 . Or should I stay with the classical layout like this one > TPA3255 classic ?
As PSU I will use adjustable switching mode power supplies, as I already got one 48V/10A. Maybe I will use cap multipliers of which I already got one, too.
best regards
Jochen
after much reading, thinking it over, deceiding, discarding the decision, reading again, etc. I'm about to join your game. First is to get an appropriate gaming device. I was into the classical design which is seen at the beginning of this thread, but the newer version seems to have some real improvements, so I am about to order two of these > 2023 improved TPA3255 . Or should I stay with the classical layout like this one > TPA3255 classic ?
As PSU I will use adjustable switching mode power supplies, as I already got one 48V/10A. Maybe I will use cap multipliers of which I already got one, too.
best regards
Jochen
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HAYK
Have a look at this in BT5 version 24.5$ with 0.002%THD+N
https://www.aliexpress.com/item/100...4c27d308e48bcbaaa88d3e263663b&ck=in_edm_other
https://www.aliexpress.com/item/100...4c27d308e48bcbaaa88d3e263663b&ck=in_edm_other
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HAYK
H
HAYK
On tokban audio store page 2 you have it.
https://www.aliexpress.com/w/wholes...detail.1000002.0&trafficChannel=af&g=y&page=2
https://www.aliexpress.com/w/wholes...detail.1000002.0&trafficChannel=af&g=y&page=2
Attachments
Ok, I took a closer look at these four now. The only one which is advertised with the 2023 model of the chip is #4. As far as I remember, I've read about this improved version of the TPA3255 in this thread, so it should be real and not just chinese marketing. For this reason #4 is still my favorite. Number 2 I find a little to expensive. Something that should change my mind?
Attachments
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HAYK
On TI site, I don't see any improved 3255 version, it must be that particular board that has new version. These boards come with two flavors, with PFFB or without. The reference I gave is probably PFFB to have so low THD.
Depends on the power level you want and the sub you are driving. For the price, you can drive around 100w from one channel into 8 ohms and leave the other channel for a spare. Not loud enough? Add another sub to channel two for another 6db. Or go with a dual voice coil sub, use one channel per coil for another 3db.
If you use 4 ohm coils instead of 8 ohm, you use lower power supply voltage and more current. My go to rig is these two boards (pic attached). Shui yuan amp board with the gold coupling caps and an alizon 36V5A AC/DC SMPS. Works like a champ and no crazy fans or anything extra required. Deal with volume/tone/mute etcetera in the separate preamp/head unit.
If you use 4 ohm coils instead of 8 ohm, you use lower power supply voltage and more current. My go to rig is these two boards (pic attached). Shui yuan amp board with the gold coupling caps and an alizon 36V5A AC/DC SMPS. Works like a champ and no crazy fans or anything extra required. Deal with volume/tone/mute etcetera in the separate preamp/head unit.
