I have a Russound X75 that no longer works and I found that one of the TDA7294 chips was blown; when attempting to remove it the traces were so worn they fell apart.
I want to buy a pair of the below modules to install, but since each board has its own rectifier is it ok to split my transformer to power a pair of boards? The transformer is a 27-0-27V Center tapped. Can I split each wire into two to run to each board, or is it better to remove the rectifiers from both boards, use a single rectifier, and split my signal off the rectifier as DC voltage
Here are the boards I am considering buying.
https://www.amazon.com/DEVMO-TDA729...054bc2&ref_=pd_hp_d_atf_ci_mcx_mr_ca_hp_atf_d
I want to buy a pair of the below modules to install, but since each board has its own rectifier is it ok to split my transformer to power a pair of boards? The transformer is a 27-0-27V Center tapped. Can I split each wire into two to run to each board, or is it better to remove the rectifiers from both boards, use a single rectifier, and split my signal off the rectifier as DC voltage
Here are the boards I am considering buying.
https://www.amazon.com/DEVMO-TDA729...054bc2&ref_=pd_hp_d_atf_ci_mcx_mr_ca_hp_atf_d
I'm attaching a service manual from a Rotel amp.
Rotel seems to have done exactly what you're describing: taken two separate bridge rectifiers with bipolar positive and negative outputs and sourced them from a single center-tapped power transformer. See schematic on page 7 of SM.
Good luck!
Rotel seems to have done exactly what you're describing: taken two separate bridge rectifiers with bipolar positive and negative outputs and sourced them from a single center-tapped power transformer. See schematic on page 7 of SM.
Good luck!
I studied over the schematic and it appears they DID split their 3 wires. However, adding a fuse to each seconday before the split wouldn't be a bad idea.
Please correct me if I am wrong here in reading the schematic.
I actually have quite a few leftover transformers from other Class AB amps that I could repurpose with these modules. I plan to use them for patio and outside amplifiers...
Please correct me if I am wrong here in reading the schematic.
I actually have quite a few leftover transformers from other Class AB amps that I could repurpose with these modules. I plan to use them for patio and outside amplifiers...
The power supply will work just fine by feeding the two modules from the same transformer without modification. Yes, the fuses are also a good idea.
One thing puzzles me though. I know nothing about the X75 and couldn't find anything about it on the Russound site, so I had a look at the Crutchfield site. They say that the X75 is a Class D amplifier whereas the TDA7294 is a Class AB linear IC. Can you clarify this point?
One thing puzzles me though. I know nothing about the X75 and couldn't find anything about it on the Russound site, so I had a look at the Crutchfield site. They say that the X75 is a Class D amplifier whereas the TDA7294 is a Class AB linear IC. Can you clarify this point?
Just one more thing. You're probably already aware of this but I thought I'd mention it anyway. Each of those TDA7294's working into an 8-ohm load with that power supply could generate up to 30 watts worth of heat. I assume that the X75 has adequate heatsinks, maybe with a fan. Proper mounting of the ICs with good heatsink compound (thermal paste) is essential.