its an active amp with 3 TDAs. To test the crossover, I used a sinewave generator. So essentially 3 TDAs and 2 small power supplies (+-12V for crossover and 5V V for mute/standby) used 14W for doing nothing and 16 W for being quite loud.
Using this power meter Power-Mate Lite 10 Amp Power Meter which is very accurate.
Finished testing now, it fills the whole house with music. Seems the speakers are pretty linear, if I don't adjust anything, some CDs sound very pale now. Checked with adB (C) meter and adjusted the TDAs, so they line up at the crossover frequencies. Compared to ear phones and radios at work which seem to have bass cranked up. And there are lots of tiny noises on the CDs which I never heared before, one there was someone walking around in the background, closing a door.
Using this power meter Power-Mate Lite 10 Amp Power Meter which is very accurate.
Finished testing now, it fills the whole house with music. Seems the speakers are pretty linear, if I don't adjust anything, some CDs sound very pale now. Checked with adB (C) meter and adjusted the TDAs, so they line up at the crossover frequencies. Compared to ear phones and radios at work which seem to have bass cranked up. And there are lots of tiny noises on the CDs which I never heared before, one there was someone walking around in the background, closing a door.
just the monoblocks or the crossovers as well? Got some busted speakers from freecycle until I sorted the problem with massive DC offset / popping speakers.I ended up redoing everything, power supplies etc back then.
Time flies, I am still happy with them.
With the monoblocks, there is also some fiddling with the caps on the signal input, so you can tweak them for high or low frequencies.
The sound is so clear now, you can hear how different some CDs are, some sound very thin
Time flies, I am still happy with them.
With the monoblocks, there is also some fiddling with the caps on the signal input, so you can tweak them for high or low frequencies.
The sound is so clear now, you can hear how different some CDs are, some sound very thin
Also, it all came down to ground issues, once that was solved it all goes well. So the board layout is crucial. Of the power supply, the filter and the monoblocks. I suppose if you don't use an active filter, that would save you some of the trouble.
Also, I got lot of help in the forum, so I cannot claim, its all my own work.
In the schematic, R10 and IC2 is to set the gain. R10 first to adjust it, IC10 is just a socket, where I then put2 resistors in, so its a fixed resistance. This is just, as its active and there are 3 different chassis, you have to set gain for each chassis individually. So you can get rid of that and just put some fixed resistor in.
The jumpers you may also not need, if you don't run them in parallel for more output. And R 11 the 1 ohm is so there is a sall resistance from signal to power ground.This is part of how to get rid of the 50Hz hum. Also, I did not use 2 monoblocks for the bass, because one was enough and it saved me all that fiddling with the DC offset. So really depends, what you want to achieve. Lots off base or something like a lens. Now it sounds like I can actually see the grain of the timber, all the paint and dust has been removed. Kind off like the singer is in the room and you can actually hear that little click when he opens his mouth.I was almost in teras, when it finally worked. Used Red house painters "songs for a blue guitar" And then some quiet songs from Tindersticks for testing. No background noise at all.
Also, I got lot of help in the forum, so I cannot claim, its all my own work.
In the schematic, R10 and IC2 is to set the gain. R10 first to adjust it, IC10 is just a socket, where I then put2 resistors in, so its a fixed resistance. This is just, as its active and there are 3 different chassis, you have to set gain for each chassis individually. So you can get rid of that and just put some fixed resistor in.
The jumpers you may also not need, if you don't run them in parallel for more output. And R 11 the 1 ohm is so there is a sall resistance from signal to power ground.This is part of how to get rid of the 50Hz hum. Also, I did not use 2 monoblocks for the bass, because one was enough and it saved me all that fiddling with the DC offset. So really depends, what you want to achieve. Lots off base or something like a lens. Now it sounds like I can actually see the grain of the timber, all the paint and dust has been removed. Kind off like the singer is in the room and you can actually hear that little click when he opens his mouth.I was almost in teras, when it finally worked. Used Red house painters "songs for a blue guitar" And then some quiet songs from Tindersticks for testing. No background noise at all.
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The hum-breaking resistor is too low I´d say . I am using 10 ohms . And take the grounds of each amp and the crossover to a common starpoint at the PSU. Use shielded cables for signal from the crossover to the amps but connect the shielding only at the crossover so you avoid creating ground loops in the first place. If you connect the shielding at both ends each amp has two ground-connections one direct to PSU and the other via the crossover so you would have 3! ground loops . Yet another detail is to place the crossover output as close to the tweeter-amp input as possible to avoid picking up high frequency signals be it by capacitive or inductive coupling. The tweeter amp and tweeter are the most sensitive to picking up this kind of noises and able to reproduce them.
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