I bought 5 Tannoy active monitors and two of them have a slight distortion across all frequencies. I’ve taken one of them to three local techs and all said they can’t fix it. They said there is nothing obviously wrong. They even test it and say it measures fine. But it’s clearly distorting.
I swapped everything around including power capacitors (mounted separate from the amp board), drivers, boards, and even the transformers. From that I worked out the issue is coming from the amplifier board which includes the board, transistors, heat sink etc.. Photo attached which is terrible I agree.
Now as you can hear, I don’t know much about electronics. There is no schematic that can be found and Tannoy is incommunicado.
Any suggestions go about finding out what the problem is? I can do things like measure resistors, capacitors, remove and replace passives etc.. I was thinking about placing a good board beside a bad one and start measuring stuff until something is different. Pretty crude.
I swapped everything around including power capacitors (mounted separate from the amp board), drivers, boards, and even the transformers. From that I worked out the issue is coming from the amplifier board which includes the board, transistors, heat sink etc.. Photo attached which is terrible I agree.
Now as you can hear, I don’t know much about electronics. There is no schematic that can be found and Tannoy is incommunicado.
Any suggestions go about finding out what the problem is? I can do things like measure resistors, capacitors, remove and replace passives etc.. I was thinking about placing a good board beside a bad one and start measuring stuff until something is different. Pretty crude.
Attachments
I’ve used my ears only. One of the techs I took them to had a tone generator and he checked at various frequencies and confirmed that there was distortion.