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Old 26th January 2013, 09:30 AM   #2601
AndrewT is offline AndrewT  Scotland
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Move the gate resistor with the FETs.
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Old 26th January 2013, 10:56 AM   #2602
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So I lift up from the board the 470Rs?
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Old 26th January 2013, 01:10 PM   #2603
Salas is offline Salas  Greece
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Yes, they should follow the physical gate pin close.
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Old 28th January 2013, 03:27 PM   #2604
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Quick question for you guys.

I have made myself a balanced version of the DCB1 and I have 3 Balanced XLR and 2 SE RCA input and on the output I have 1 Balanced XLR and one SE RCA.

I'm using one DCB1 per balanced channel and when using it in SE I do the same thing but connect the signal to +phase and ground to signal ground.

I wanted to know on the RCA input, if I should shunt the antiphase (-phase) to ground or put in a resistor for a fake load since I'm only using one channel per side in SE mode.

Thanks
Do
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Old 28th January 2013, 03:50 PM   #2605
Salas is offline Salas  Greece
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All XLR to RCA converter plugs ground it but it can up THD in the balanced source so better terminate it with ~600 Ohm for the redundant phase.
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Old 28th January 2013, 03:55 PM   #2606
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Quote:
Originally Posted by Salas View Post
All XLR to RCA converter plugs ground it but it can up THD in the balanced source so better terminate it with ~600 Ohm for the redundant phase.
OK, thanks!

I'll terminate the -phase to ground with a 600 ohm resistor.

Thanks
Do
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Old 29th January 2013, 07:58 AM   #2607
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hi,

few quick questions regarding two 35VA pcb 15v transformers I have paralleled. The adjustment R is 2 ohms making it 1.77VDC and 1.92VDC on the rails. Wattage meter shows about 48VA of constant consuming. So as advised by Andrew I'm still in a safe zone

1. Trafos have 2x110v primaries, is it safe to use them? Checked the mains during the week and it varies from 218 till 228v.

2. I get quite audible hum when I'm close to them (about 10cm). Could that be reduced somehow? Will mu-metal be helpful here?
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Old 29th January 2013, 08:53 AM   #2608
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Default Oh my god

You can not place transformers so near the pot. It will off course result in hum. The 2x 110 is no problem when coupled i series.
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Old 29th January 2013, 10:15 AM   #2609
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You can not place transformers so near the pot. It will off course result in hum. The 2x 110 is no problem when coupled i series.
just to clarify, the pot is just there hanging and the buffer is not connected to any source. By the hum I meant physical hum from transformers.
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Old 29th January 2013, 11:17 AM   #2610
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just to clarify, the pot is just there hanging and the buffer is not connected to any source. By the hum I meant physical hum from transformers.
ok then you have to buy new transformers .
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