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The readings you're getting now are normal.
It probably won't hurt to run the amp at low power (for testing) with the cap you removed. You can solder a replacement to the pads on the top of the board. Apply a dot of adhesive between the cap and the board to prevent the leads from being stressed. This is better than taking it out of the heatsink unless you have a lot of experience repairing amps.
R70 is a 1k resistor and connects the secondary ground to the primary ground. That's the 1000 ohms (approximately) that you read from the RCA shields to the amp ground.
The readings you're getting now are normal.
It probably won't hurt to run the amp at low power (for testing) with the cap you removed. You can solder a replacement to the pads on the top of the board. Apply a dot of adhesive between the cap and the board to prevent the leads from being stressed. This is better than taking it out of the heatsink unless you have a lot of experience repairing amps.
R70 is a 1k resistor and connects the secondary ground to the primary ground. That's the 1000 ohms (approximately) that you read from the RCA shields to the amp ground.
The forum won't let me upload a 10meg picture 
I'll try it again.
So can I replace capacitors C30 & C34 (683K63) with these;
Epcos | Passives | Capacitors | Plastic Film | Metallised 125°C |B32529C0154J.
Also, being that the 'stutter, wobble thing' only came in at moderate volume, should I wait and get these in the morning?
That place is just around the corner from me...
Thanks Perry, you have been a MASSIVE help
I'll try it again.
So can I replace capacitors C30 & C34 (683K63) with these;
Epcos | Passives | Capacitors | Plastic Film | Metallised 125°C |B32529C0154J.
Also, being that the 'stutter, wobble thing' only came in at moderate volume, should I wait and get these in the morning?
That place is just around the corner from me...
Thanks Perry, you have been a MASSIVE help
Me again
I have now changed the 2 caps but to no avail.
I grilled the previous owner about how the amp was treated to get any other ideas.
He says, he ran 2 1000w subs on it @ 1ohm - the subs went up in smoke.
Voltage was always very good etc... I think he might of clipped the life out them.
The other thing he said was, he tried to install a manual bass controller from a SS Rubicon amplifier, that never worked so he took it off... I don't know if this, in turn, damaged anything?
I have now changed the 2 caps but to no avail.
I grilled the previous owner about how the amp was treated to get any other ideas.
He says, he ran 2 1000w subs on it @ 1ohm - the subs went up in smoke.
Voltage was always very good etc... I think he might of clipped the life out them.
The other thing he said was, he tried to install a manual bass controller from a SS Rubicon amplifier, that never worked so he took it off... I don't know if this, in turn, damaged anything?
Those components are in parallel with other components. That's what's causing them to read lower than they really are.
From the diagram, I don't think using the wrong controller could have caused any damage.
Do any of the other controls like the bass boost or the subsonic filter make a difference?
From the diagram, I don't think using the wrong controller could have caused any damage.
Do any of the other controls like the bass boost or the subsonic filter make a difference?
Like the gain pot. When I turn the bass boost up so far, it seems to do the same thing.
Subsonic filter appears to be unaffected.
I just tried another 2 sources and it does it with them too. Seems to be only when something is connected - doesn't have to be playing anything either.
Maybe the 'stutter' at a certain frequency is a whole new problem?
I'll do a video or 2 today and upload them Well I'll give it a damn good try anyway.
Thanks Perry
Subsonic filter appears to be unaffected.
I just tried another 2 sources and it does it with them too. Seems to be only when something is connected - doesn't have to be playing anything either.
Maybe the 'stutter' at a certain frequency is a whole new problem?
I'll do a video or 2 today and upload them Well I'll give it a damn good try anyway.
Thanks Perry
To be honest I cannot really say if it's an audio or power issue.
I checked and all voltages and it appears (to me anyway) to be OK circa 14V
1 thing I would like to clarify on though is the transformer noise. Both sound loudish to me, most likely because of the size of them.
When you turn the volume up they go from making a smooth noise to, only what I can describe as a distorted noise. Almost like they are being throttled in some way. I think you could almost work out the song by the noise they make (no subwoofer attached).
Is this normal on big amplifiers?
Thank you for all your help Perry!
I checked and all voltages and it appears (to me anyway) to be OK circa 14V
1 thing I would like to clarify on though is the transformer noise. Both sound loudish to me, most likely because of the size of them.
When you turn the volume up they go from making a smooth noise to, only what I can describe as a distorted noise. Almost like they are being throttled in some way. I think you could almost work out the song by the noise they make (no subwoofer attached).
Is this normal on big amplifiers?
Thank you for all your help Perry!
UPDATE!
I removed ALL my stereo today and fitted it to my work van in an attempt to rule out any defective equipment/wiring.
My Alpine headunit wont put out a clean signal at about 30-38Hz (approx)
The reason I thought it was the Lanzar is because my midbass' are crossed at 50Hz 24db/Oct.
I feel so bloody stupid now, I just took the RCA outputs (+ve) for granted.
The amp STILL has problems with the gain and bass boost dials though, so I'll start a new thread so as to not confuse the matter.
Many thanks for all your help Perry, you and your site have given me much knowledge and motivation. I will be treating myself to a copy of your book when funds allow, as this is becoming a very interesting hobby
I removed ALL my stereo today and fitted it to my work van in an attempt to rule out any defective equipment/wiring.
My Alpine headunit wont put out a clean signal at about 30-38Hz (approx)
The reason I thought it was the Lanzar is because my midbass' are crossed at 50Hz 24db/Oct.
I feel so bloody stupid now, I just took the RCA outputs (+ve) for granted.
The amp STILL has problems with the gain and bass boost dials though, so I'll start a new thread so as to not confuse the matter.
Many thanks for all your help Perry, you and your site have given me much knowledge and motivation. I will be treating myself to a copy of your book when funds allow, as this is becoming a very interesting hobby
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