TDA1558Q - output power THD = 10%; 4 Ω − 6W THD = 10%; 2 Ω− 11W
In single mode, the amplifier has 2x11W at 2 ohms (2x6W at 4ohms) and in bridged mode it has 1x22W at 4ohm, all that at 10%THD which is terrible. It's a car amplifier, usually these amplifiers can handle low impedances. The problem with that amp is low power and high distortion, and probably a bad power supply .
So for a 2+1 system, you need to get something better, stronger and with less THD. Let's say some D class from China that has two stereo channels and one SUB channel (TPA3116 and similar).
https://www.ebay.com/itm/265031776673
Output power: 100W+2*50W (4Ω) - This is a little too optimistic, but you can count on half this power at 4 ohms, with a good SMPS power supply 24VDC 8-10A.
This is a DIY forum, jump right into building an amp. If you don't want to or can't, there are cheap ready-made devices much better than that modest car amplifier. 😎
In single mode, the amplifier has 2x11W at 2 ohms (2x6W at 4ohms) and in bridged mode it has 1x22W at 4ohm, all that at 10%THD which is terrible. It's a car amplifier, usually these amplifiers can handle low impedances. The problem with that amp is low power and high distortion, and probably a bad power supply .
So for a 2+1 system, you need to get something better, stronger and with less THD. Let's say some D class from China that has two stereo channels and one SUB channel (TPA3116 and similar).
https://www.ebay.com/itm/265031776673
Output power: 100W+2*50W (4Ω) - This is a little too optimistic, but you can count on half this power at 4 ohms, with a good SMPS power supply 24VDC 8-10A.
This is a DIY forum, jump right into building an amp. If you don't want to or can't, there are cheap ready-made devices much better than that modest car amplifier. 😎
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When you turn it down from 2 times 22 W to 2 times 17 W, the distortion drops to 0.5 %, at 2 times 1 W it is 0.1 %. That 22 W is basically in hard clipping.
It's a stereo bridge-tied-load chip, by the way. Drive it in non-bridged mode and you have four channels, two of which invert.
https://pdf1.alldatasheet.com/datasheet-pdf/view/19228/PHILIPS/TDA1558Q.html
It's a stereo bridge-tied-load chip, by the way. Drive it in non-bridged mode and you have four channels, two of which invert.
https://pdf1.alldatasheet.com/datasheet-pdf/view/19228/PHILIPS/TDA1558Q.html
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There are good car amplifiers, for example this TDA7396 plays great. I made it to have a small amplifier to try out speakers and other devices in some crappy plastic box. I use an original ASUS brick power supply 19.5V 120W from an old laptop.
Power with 1% THD is 2x15W at 8ohm, 2x30W at 4ohm. Max. power is 2x45W at 2 ohms (and it is connected in bridge mode!).
The amplifier has balanced inputs, for the SE connection to the preamp I use BAL/SE adapters.
This is easily assembled on a raster board. Only the board must be turned at 45 degrees due to the spacing of the legs on the TDA. Vired vith VDHCS18 and some silver plated copper vires in teflon insulation.
Power with 1% THD is 2x15W at 8ohm, 2x30W at 4ohm. Max. power is 2x45W at 2 ohms (and it is connected in bridge mode!).
The amplifier has balanced inputs, for the SE connection to the preamp I use BAL/SE adapters.
This is easily assembled on a raster board. Only the board must be turned at 45 degrees due to the spacing of the legs on the TDA. Vired vith VDHCS18 and some silver plated copper vires in teflon insulation.
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Ok, I just casually looked at the datasheet. In any case, if it is not powered by a car battery but by some weak power supply, these data are not valid, problems will start earlier depending on the power supply.
Thanks for all your help. It all seems to work well. All the channels are 6 ohms. I have a couple of systems using TPA3116 variants, this was never going to compete.
I was simply putting together scraps rather than throw them out.
It was a Tannoy SFX box, with a Soundworks driver coupled to a Microlab FC330 plate amp. It's sound a boomy but that's to be expected.
I was simply putting together scraps rather than throw them out.
It was a Tannoy SFX box, with a Soundworks driver coupled to a Microlab FC330 plate amp. It's sound a boomy but that's to be expected.