A quick question for all you chip amp experts 😀 I need to build an amp for an all active OB speaker setup using eminence alpha 15a's for bass. Is there a particular chip that would perform best for this application. It will strictly be for bass.
I had a similar driver in a h-frame that needed little til no EQ and despite dipole loss you might be OK with a chipamp of let´s say 50W with proper transformer and capacitance (or regulated SMPS).
If you EQ the driver heavily I´d go for an amp with >>50W.
I´m using a cheap Aiyima A04, which is class-d. Supplied with 36V it can (theoretically) deliver peaks of >80W that my LM3886-amps can´t.
I feel "safer" with that solution but probaby don´t need it listening at low SPLs.
Look at the TDA7293 if you want class-AB:
Xmas Amp - Dibya's TDA7293 by Jhofland
Class-D (TPA3255) can be had for 70$ or so (3e-audio or look into the forum´s offerings)
For mid&treble I´d choose LM3886 or discrete designs.
If you EQ the driver heavily I´d go for an amp with >>50W.
I´m using a cheap Aiyima A04, which is class-d. Supplied with 36V it can (theoretically) deliver peaks of >80W that my LM3886-amps can´t.
I feel "safer" with that solution but probaby don´t need it listening at low SPLs.
Look at the TDA7293 if you want class-AB:
Xmas Amp - Dibya's TDA7293 by Jhofland
Class-D (TPA3255) can be had for 70$ or so (3e-audio or look into the forum´s offerings)
For mid&treble I´d choose LM3886 or discrete designs.
Thanks I will have a look. my setup does require a fair bit of eq for the bass. I am currently using lm1876 and am just finishing up a my refc for mids.
I had seen the tda7293. Will have a closer look.
I had seen the tda7293. Will have a closer look.
What´s your setup like? 3-way active so using 3 stereo-amps?
One Alpha 15A per side?
I´d say LM1876 makes a nice amp for mid+tweeter.
I usually am not the type to recommend high-wattage amps but with an EQ on a dipole bass you will probably need more reserves than the LM1876 can offer.
One Alpha 15A per side?
I´d say LM1876 makes a nice amp for mid+tweeter.
I usually am not the type to recommend high-wattage amps but with an EQ on a dipole bass you will probably need more reserves than the LM1876 can offer.
Yes it is an active 3 way. using mini dsp for now. The lm1876 is a nice sounding chip for sure.I will see how the my- refc compares when Its ready. My bass set up is the same as emerald physics ( the aperture loaded ) style. I am quite happy with the bass as far as sound goes but It requires a lot of eq to get the spl's from all the drivers even. I am currently using a topping tp20 for bass but I do realize it is not powerful enough for best results.
If you´re happy now, then you are in no rush.
Think about which solution makes sense.
In systems like this it´s often about the power supply for all amps and simply being practical. Grounding, cabling, cases etc.
I´m using a mixture of SMPS and transformer for now but eventually would like something more compact.
The LM3886 with all its different implementations make nice amps for sure.
That one might suffice for bass duties too but if you´ll have to buy a transformer anyway give the TDA7293 a look. Just a wee bit more power.
Your speaker sounds interesting. Did you post a picture of it somewhere?
Think about which solution makes sense.
In systems like this it´s often about the power supply for all amps and simply being practical. Grounding, cabling, cases etc.
I´m using a mixture of SMPS and transformer for now but eventually would like something more compact.
The LM3886 with all its different implementations make nice amps for sure.
That one might suffice for bass duties too but if you´ll have to buy a transformer anyway give the TDA7293 a look. Just a wee bit more power.
Your speaker sounds interesting. Did you post a picture of it somewhere?
Free tested and proven TDA7293 design here if you are going that way:
Xmas Amp - Dibya's TDA7293 by Jhofland
If you only need about 30w, the TDA8932 class D amp has superb bass. It is also dirt cheap. In PBTL mode, it can drive 4ohms easily and only needs a 24v smps brick.
Xmas Amp - Dibya's TDA7293 by Jhofland
If you only need about 30w, the TDA8932 class D amp has superb bass. It is also dirt cheap. In PBTL mode, it can drive 4ohms easily and only needs a 24v smps brick.
I have not posted a pic of them yet, but I will soon. They are obviously still a work in progress.
My lm1876 was my first attempt at building a chip amp. they use two smps per channel in series. I must have lucked out.I just built them on small vero boards and they are dead quiet and sound great.
Depends. What's the impedance of your drivers?
If 4 Ω, a parallel pair of LM3886 should provide plenty of power.
Tom
If 4 Ω, a parallel pair of LM3886 should provide plenty of power.
Tom
No they are higher than that. They are closer to 8.I bought a pair of 32
tda 8932 boards just because they are so cheap. Once the myref c's are working I can do some experimenting and go from there.
tda 8932 boards just because they are so cheap. Once the myref c's are working I can do some experimenting and go from there.
Well I got my tda8932 boards. I can't believe how tiny they are.Almost too small to solder wires too. I will be doing some experimenting over the next few days.I am usually a tube guy but I am getting quite hooked on these great sounding chip amps.
They are tiny - you mean the $3 blue mono PBTL ones right? If they were properly made with decent sized quality components (bigger inductors) they would be a bit bigger.
Yes I figure for that price they wouldn't be great quality. I had to reorder one because one of them had a cap just break off when I barely touched it. But they should at least give me an idea of the sound. At some point I will def want to upgrade.
Better late than never 😉. It's a simple China Kit and I'm driving a Mivoc AW 3000 in 50 Liters sealed with it. I'm pretty happy with the Performance, but I'll try a triple TDA7293 just because of "why not?" 😉.
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Those boards actually look good for being from china. The little tda 8932 boards I got surprised the hell out of me. The amount of bass for the size is quite impressive. I may do some mods at some point. I,d really like to hear what they are like when better implemented. I finally finished the myref c amps. just working on getting it all in some proper cases.