700B Build
- Thread starter Hexis22
- Start date
Made some measurements after mounting the transformer to find proper AC connection.
Following Joe's instructions (re-posted below), I found the primary winding closest to the core and farthest from the secondary to reduce coupling in hopes of lowering the noise floor. The AC Line (Black) will be connected to this side of the primary.
Following Joe's instructions (re-posted below), I found the primary winding closest to the core and farthest from the secondary to reduce coupling in hopes of lowering the noise floor. The AC Line (Black) will be connected to this side of the primary.
- Put your DMM on the VAC scale
- DMM lead 1 to secondary center tap, other secondary wires left floating
- DMM lead 2 to safety ground of your mains plug
- Shunt across your DMM with 100K ohm resistor to provide a light load to the transformer coupling effect
- Connect L and N to the primaries in one direction. Take measurement
- Flip the L and N to the primaries to get the other direction. Take measurement
- The lowest measurement is the orientation that you want to use.
Looks Like a better way to do it than switching the 2-Prong cord around.
and knowing this before adding 3-Prong Plug. Will have to try this for the 400II and 700II. I see in your transformer bolts- did you order SS and what size and length worked?
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Hello every one. My name is Mike and this 700b build was for me. I have had the amp for a while now and I can't say enough about this amp I just love this thing! Eric you did a top notch hob on this build I can't thank.you enough. I have it driving a pair of Bowers and wilkins 802D. The sound it creates is outstanding and absolutely no noise. I have to say it is the best sounding amp I have owned it beats my McIntosh. I love the power of this amp with zero clipping. Eric well done!!!!
Yes, I use Stainless hardware for mounting the transformer.
If implementing the bolt, washer, isolation bushing as pictured below, the bolt length required for a 700 transformer is 4 1/4". Given that is not a standard length, I purchased 4 1/2" and cut 1/4".
I reused the original washers and drilled out ID to fit isolation bushings.
Bolt info (1/4" - 28, 4 1/2" long): https://www.mcmaster.com/catalog/129/3504/90696A191
Isolation Bushing: https://www.amazon.com/dp/B00MND8L6...Z2W0R48D&psc=1&ref_=list_c_wl_lv_ov_lig_dp_it
If implementing the bolt, washer, isolation bushing as pictured below, the bolt length required for a 700 transformer is 4 1/4". Given that is not a standard length, I purchased 4 1/2" and cut 1/4".
I reused the original washers and drilled out ID to fit isolation bushings.
Bolt info (1/4" - 28, 4 1/2" long): https://www.mcmaster.com/catalog/129/3504/90696A191
Isolation Bushing: https://www.amazon.com/dp/B00MND8L6...Z2W0R48D&psc=1&ref_=list_c_wl_lv_ov_lig_dp_it
Yes, I use Stainless hardware for mounting the transformer.
If implementing the bolt, washer, isolation bushing as pictured below, the bolt length required for a 700 transformer is 4 1/4". Given that is not a standard length, I purchased 4 1/2" and cut 1/4".
I reused the original washers and drilled out ID to fit isolation bushings.
Bolt info (1/4" - 28, 4 1/2" long): https://www.mcmaster.com/catalog/129/3504/90696A191
Isolation Bushing: https://www.amazon.com/dp/B00MND8L6...Z2W0R48D&psc=1&ref_=list_c_wl_lv_ov_lig_dp_it
If implementing the bolt, washer, isolation bushing as pictured below, the bolt length required for a 700 transformer is 4 1/4". Given that is not a standard length, I purchased 4 1/2" and cut 1/4".
I reused the original washers and drilled out ID to fit isolation bushings.
Bolt info (1/4" - 28, 4 1/2" long): https://www.mcmaster.com/catalog/129/3504/90696A191
Isolation Bushing: https://www.amazon.com/dp/B00MND8L6...Z2W0R48D&psc=1&ref_=list_c_wl_lv_ov_lig_dp_it
I'm working on the 400II transformer now.
I did the voltage test for Hot and N (which is a different transformer can be 120vac or 220vac ) and it worked great. It was .2vac and 6vac this is a vary good test to use before soldering to IEC Male Connector. It ended up like I thought it would be. (Phase Liner schematics could be different or incomplete or wrong) Its always good to Double check. It ended up w
AC Hot-Blue and Brown wires,
AC N- Blue w a Yellow strip and Brown w a yellow Strip wires.
Steve, every PL dual primary transformer in 400 S2, 700 S2, and PL2000 S2, I've tested using Joe's method came up opposite of your results.
The striped primaries have gone to Line, and the solid color primaries have gone to Neutral.
See Joe's post #147 and # 150 in the link for test procedure.
https://forums.phxaudiotape.com/threads/pl-700-pro-build.9965/page-8.
Not saying your wrong, just saying here's the procedure if you haven't seen it.
The striped primaries have gone to Line, and the solid color primaries have gone to Neutral.
See Joe's post #147 and # 150 in the link for test procedure.
https://forums.phxaudiotape.com/threads/pl-700-pro-build.9965/page-8.
Not saying your wrong, just saying here's the procedure if you haven't seen it.
Yes, I use Stainless hardware for mounting the transformer.
If implementing the bolt, washer, isolation bushing as pictured below, the bolt length required for a 700 transformer is 4 1/4". Given that is not a standard length, I purchased 4 1/2" and cut 1/4".
I reused the original washers and drilled out ID to fit isolation bushings.
Bolt info (1/4" - 28, 4 1/2" long): https://www.mcmaster.com/catalog/129/3504/90696A191
Isolation Bushing: https://www.amazon.com/dp/B00MND8L6...Z2W0R48D&psc=1&ref_=list_c_wl_lv_ov_lig_dp_it
If implementing the bolt, washer, isolation bushing as pictured below, the bolt length required for a 700 transformer is 4 1/4". Given that is not a standard length, I purchased 4 1/2" and cut 1/4".
I reused the original washers and drilled out ID to fit isolation bushings.
Bolt info (1/4" - 28, 4 1/2" long): https://www.mcmaster.com/catalog/129/3504/90696A191
Isolation Bushing: https://www.amazon.com/dp/B00MND8L6...Z2W0R48D&psc=1&ref_=list_c_wl_lv_ov_lig_dp_it
Steve, every PL dual primary transformer in 400 S2, 700 S2, and PL2000 S2, I've tested using Joe's method came up opposite of your results.
The striped primaries have gone to Line, and the solid color primaries have gone to Neutral.
See Joe's post #147 and # 150 in the link for test procedure.
https://forums.phxaudiotape.com/threads/pl-700-pro-build.9965/page-8.
Not saying your wrong, just saying here's the procedure if you haven't seen it.
The striped primaries have gone to Line, and the solid color primaries have gone to Neutral.
See Joe's post #147 and # 150 in the link for test procedure.
https://forums.phxaudiotape.com/threads/pl-700-pro-build.9965/page-8.
Not saying your wrong, just saying here's the procedure if you haven't seen it.
A- I will check again. I see the AC Ground wire was hooked up to the Case frame which grounds the Transformer ? I did not do these step.
1- I will have to check my AC is correct first (Check my cord and w a ac power tester also going to a my main power strips and my test power strips. and even the 120vac outlet
2- Test w and wo ground hooked up (That .2vac is really low compare to you test results)