You will need to isolate the connector from the chassis. If you can find fiber shoulder washers that fit the jacks, that will work. Otherwise buy better jacks - most people use gold plated jacks that come with insulating washers.
In that case connect each trafo (secondaries in series) separately: one to AC1-AC1 pads, the other to AC2-AC2 on rectifier board as shown here: http://www.diyaudio.com/forums/audi...ne-kit-building-instructions.html#post1508798
The other option would be mounting RCAs on non metal plate first (plastic or similar) and then attaching such assembly to the rest of the chassis.
Hey guys,
I'm sad to inform u that disaster has struck
After playing beautifully for several weeks this went wrong. While listening to some loud music suddenly a loud buzz sounded from my right speaker. I quickly shut the amp off. When I looked inside the input wire had made connection with one of the rectifiers on the power board. Looking backwards I have been to sloppy with some of the wires that carry no sleeving. Lesson learned, now for the repair
I just did some measurements, here are the results:
- 34V between V+ and PG+ (seems fine)
- 34V between V- and PG- (seems fine)
- 32.8V offset between the speaker posts with no load (seems huge, the other channel measures 48mV)
- 2V offset between the speak posts with load (seems high, the other channel measures 30mV)
From my measurements I conclude that the damage must be on the amplifier board itself. Since there is not much there (2 caps, 3 resistors and the chip my best guess is that the chip is fried. What do u guys think? Any way I can verify this by measuring?
Thanks!
Regards,
Erik
I'm sad to inform u that disaster has struck
After playing beautifully for several weeks this went wrong. While listening to some loud music suddenly a loud buzz sounded from my right speaker. I quickly shut the amp off. When I looked inside the input wire had made connection with one of the rectifiers on the power board. Looking backwards I have been to sloppy with some of the wires that carry no sleeving. Lesson learned, now for the repair I just did some measurements, here are the results:
- 34V between V+ and PG+ (seems fine)
- 34V between V- and PG- (seems fine)
- 32.8V offset between the speaker posts with no load (seems huge, the other channel measures 48mV)
- 2V offset between the speak posts with load (seems high, the other channel measures 30mV)
From my measurements I conclude that the damage must be on the amplifier board itself. Since there is not much there (2 caps, 3 resistors and the chip my best guess is that the chip is fried. What do u guys think? Any way I can verify this by measuring?
Thanks!
Regards,
Erik
Hey guys,
I'm sad to inform u that disaster has struck
I just did some measurements, here are the results:
- 34V between V+ and PG+ (seems fine)
- 34V between V- and PG- (seems fine)
- 32.8V offset between the speaker posts with no load (seems huge, the other channel measures 48mV)
- 2V offset between the speak posts with load (seems high, the other channel measures 30mV)
From my measurements I conclude that the damage must be on the amplifier board itself. Since there is not much there (2 caps, 3 resistors and the chip my best guess is that the chip is fried. What do u guys think? Any way I can verify this by measuring?
Thanks!
Regards,
Erik
I think you need to replace your chip.
new gainclone builder
Hi Peter,
I bought the pre kit and now have problem with one channel, one offset is 7mV while the other is -35mV.
I am using the SG ground and OG ground as you demonstrated.
The V+ and V- seemed OK. I am using a 50K pot, two amp boards are
the same and there is not anything more to check? Is the chip fried?
Regards,
Jason
Hi Peter,
I bought the pre kit and now have problem with one channel, one offset is 7mV while the other is -35mV.
I am using the SG ground and OG ground as you demonstrated.
The V+ and V- seemed OK. I am using a 50K pot, two amp boards are
the same and there is not anything more to check? Is the chip fried?
Regards,
Jason
Are those the offsets from the amp? If so, they are perfectly fine.
The offset will depend on a particular chip and shunt resistance value (R2) as demonstrated here: http://www.diyaudio.com/forums/audi...-kit-building-instructions-5.html#post1524877
The offset will depend on a particular chip and shunt resistance value (R2) as demonstrated here: http://www.diyaudio.com/forums/audi...-kit-building-instructions-5.html#post1524877
Peter
After successfully completing my first chip amp, i am now looking to build a second amp with a slightly better design. i.e. better case/layout.
I have a set of KEF Q5 speakers which support Biamping, i.e. seperate binding posts for HF/LF.
Have you got a guide/any advice for bi amping and would you use different components on the amp pcb for the high and low frequency channels?
Regards
Dan
After successfully completing my first chip amp, i am now looking to build a second amp with a slightly better design. i.e. better case/layout.
I have a set of KEF Q5 speakers which support Biamping, i.e. seperate binding posts for HF/LF.
Have you got a guide/any advice for bi amping and would you use different components on the amp pcb for the high and low frequency channels?
Regards
Dan
Wrong resistors?
Hi,
Received my kit a few days ago. Just started on the soldering.
The R3 resistors in my kit seems to be 751 ohm, not 680 as mentioned in the building instructions. (violet, green, brown, brown). Is this the correct resistors, or have I mixed up something?
By the way: Great service Peter! The "samples" package went through the customs without any tax demands
Regards
Erik
Hi,
Received my kit a few days ago. Just started on the soldering.
The R3 resistors in my kit seems to be 751 ohm, not 680 as mentioned in the building instructions. (violet, green, brown, brown). Is this the correct resistors, or have I mixed up something?
By the way: Great service Peter! The "samples" package went through the customs without any tax demands
Regards
Erik