Hi,
I have an Hitachi HA-4700 that sounds great, but the left channel is about 1db down, all across the frequency range. I have recapped it and set the bias. I checked the preamps and both have identical output. The power rails are also identical. I also changed all the fuse resistors in the power amp stage. I'm beginning to think it must be one of the power transistors or the volume pot (which would be impossible to get). I replaced the balance pot a while ago, so I know it's not that.
Anyone got any other ideas?
Cheers,
Theo
I have an Hitachi HA-4700 that sounds great, but the left channel is about 1db down, all across the frequency range. I have recapped it and set the bias. I checked the preamps and both have identical output. The power rails are also identical. I also changed all the fuse resistors in the power amp stage. I'm beginning to think it must be one of the power transistors or the volume pot (which would be impossible to get). I replaced the balance pot a while ago, so I know it's not that.
Anyone got any other ideas?
Cheers,
Theo
Confirm/emilinate the volume pot by turning up to full volume and feeding it with an appropriately low (mono) input signal (from a sig gen)
