Hello,
This is a project I keep returning to. I've used to have a pair of Dynacord Mosquito S boxes, what I've used sometime on parties with a Marshall Leach amplifier I've built in the 90s. Since that I've built a lot of amps, but no one class D. While in the last 15 years at home I've preferred single ended triode amps, I was playing with the Tripath amplifier for a while and I did accepted it is nice.
Now, some time ago one side of the amplifier died and it killed some speakers in one box.
In the box remained, I did splitted wiring inside, now I have 4 speaker left on one side, 4 speaker right on the other side. (The high is splitted as well, although, it does not do much, "crossing freq" is quite high.)
In the original config, with 8 speakers + 2 high, this is the specs on the box:
but this spec is not just some "artificial dreamworld" as on most speakers. This guy can put out some really serious sound pressure.
So, I've tried one box, splitted wiring to 2 sides with a good transistor amp and it is still awesome. It eats the largest boomboxes as breakfast on rock, acoustic. It has excellent midrange and good base and OK highs. It is not as good on music what requires a box to work in 20-50Hz, but I do not care, I do not need that.
Now, the problem is, I need an amplifier instead of the one I've borrowed. I did tried a TDA 7498 based module with BT receiver on 12 and 18V, but it was a complete failure.
One of the big problems was, the switch on beep or any warning beep it make is just so loud, it is not far from being painful (the box has some good efficiency also) from a meter distance. Also, the minimum volume is very high. The other problem was, even on mid volumes, it quickly starts to loose power. At a bass drum it just fades momentary. First, I thought the SMPSU is not fast enough, so I've hooked an oscilloscope on the DC line, but did not noticed any more drop then a few mV. Then I've also connected it to a 100Ah lead acid battery and it was the same. I've used 4mm2 wires second time and only about 0.5m length.
I have now a decent BT receiver and also a usb dac, but need power amplifier module(s).
What modules would you suggest? What DC level should I use? I'm looking for amplifier only, not combined with BT receiver. I would use with usb audio mostly anyway and will need microphone input also, so that is a separate, now less important issue.
Price also does matter. This is an "ad hoc use" kind of project and do not want to spend hundreds of EUR on it - if possible. With the "if possible" I mean, if you do not recommend cheap modules from China, please reply openly, if it will sound crap than it is just wast of time and money. I know it is difficult to define what is crap, but I can declare, I'm not looking for sound quality like at home, but do not tolerate the overvalued large boomboxes either, what is good on disco, but fails on an acoustic guitar.
Do you think TPA3255 would do better if I can find a decent built module built with that?
What Voltage shold I need to feed it?
Would you recommend other module?
I do not even know what power level I should look at. On the specs, the TPA3255 could blow out my speakers easy, but after the disappointment in the TDA7498 module ... I'm not sure any more. ... but I would also understand if it is not about the IC, but about how it is built around.
Thanks a lot!
JG
This is a project I keep returning to. I've used to have a pair of Dynacord Mosquito S boxes, what I've used sometime on parties with a Marshall Leach amplifier I've built in the 90s. Since that I've built a lot of amps, but no one class D. While in the last 15 years at home I've preferred single ended triode amps, I was playing with the Tripath amplifier for a while and I did accepted it is nice.
Now, some time ago one side of the amplifier died and it killed some speakers in one box.
In the box remained, I did splitted wiring inside, now I have 4 speaker left on one side, 4 speaker right on the other side. (The high is splitted as well, although, it does not do much, "crossing freq" is quite high.)
In the original config, with 8 speakers + 2 high, this is the specs on the box:
but this spec is not just some "artificial dreamworld" as on most speakers. This guy can put out some really serious sound pressure.
So, I've tried one box, splitted wiring to 2 sides with a good transistor amp and it is still awesome. It eats the largest boomboxes as breakfast on rock, acoustic. It has excellent midrange and good base and OK highs. It is not as good on music what requires a box to work in 20-50Hz, but I do not care, I do not need that.
Now, the problem is, I need an amplifier instead of the one I've borrowed. I did tried a TDA 7498 based module with BT receiver on 12 and 18V, but it was a complete failure.
One of the big problems was, the switch on beep or any warning beep it make is just so loud, it is not far from being painful (the box has some good efficiency also) from a meter distance. Also, the minimum volume is very high. The other problem was, even on mid volumes, it quickly starts to loose power. At a bass drum it just fades momentary. First, I thought the SMPSU is not fast enough, so I've hooked an oscilloscope on the DC line, but did not noticed any more drop then a few mV. Then I've also connected it to a 100Ah lead acid battery and it was the same. I've used 4mm2 wires second time and only about 0.5m length.
I have now a decent BT receiver and also a usb dac, but need power amplifier module(s).
What modules would you suggest? What DC level should I use? I'm looking for amplifier only, not combined with BT receiver. I would use with usb audio mostly anyway and will need microphone input also, so that is a separate, now less important issue.
Price also does matter. This is an "ad hoc use" kind of project and do not want to spend hundreds of EUR on it - if possible. With the "if possible" I mean, if you do not recommend cheap modules from China, please reply openly, if it will sound crap than it is just wast of time and money. I know it is difficult to define what is crap, but I can declare, I'm not looking for sound quality like at home, but do not tolerate the overvalued large boomboxes either, what is good on disco, but fails on an acoustic guitar.
Do you think TPA3255 would do better if I can find a decent built module built with that?
What Voltage shold I need to feed it?
Would you recommend other module?
I do not even know what power level I should look at. On the specs, the TPA3255 could blow out my speakers easy, but after the disappointment in the TDA7498 module ... I'm not sure any more. ... but I would also understand if it is not about the IC, but about how it is built around.
Thanks a lot!
JG