Since the UA2192 does not like Balanced to SE cabling, I added a neurochrome buffer on input to the DCB1. This take balanced input, and converts to SE then connects to Volume control, and the rest is the usual DCB1. I just used the 10V power available from the DCB1 to drive the buffer board.
The results are excellent.
If you are looking for a simple way to add balanced, I don't see a downside.
The results are excellent.
If you are looking for a simple way to add balanced, I don't see a downside.
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Is there any difference between :
1) connecting the output shields together and using a single ground wire to the board, and
2) running a single wire from each output to the board?
Electrically it's the same, but in practice, choice two allows for each ground to be twisted around the signal.
Am I overthinking this? Does it matter?
1) connecting the output shields together and using a single ground wire to the board, and
2) running a single wire from each output to the board?
Electrically it's the same, but in practice, choice two allows for each ground to be twisted around the signal.
Am I overthinking this? Does it matter?
Excellent. Thank you!
I'm chasing down a channel that stopped working after removing the white Input/output signal plugs. They were always a problem on my build -- they could be intermittent at times. The volume control ohmed out ok when I checked it.
I don't have much build experience, so it is probably something I did...... soldering the output wiring directly to the pins of the connector was probably a bad idea.
Can I replace with a terminal block?
I think the balanced buffer is OK, as the same output channel still works no matter which input from the buffer is connected as left or right.
But I'll recheck again tonight to make sure. The way I built it makes is hard to work on -- lack of experience again.
I'm chasing down a channel that stopped working after removing the white Input/output signal plugs. They were always a problem on my build -- they could be intermittent at times. The volume control ohmed out ok when I checked it.
I don't have much build experience, so it is probably something I did...... soldering the output wiring directly to the pins of the connector was probably a bad idea.
Can I replace with a terminal block?
I think the balanced buffer is OK, as the same output channel still works no matter which input from the buffer is connected as left or right.
But I'll recheck again tonight to make sure. The way I built it makes is hard to work on -- lack of experience again.
I found the issue. One leg of the TKD pot broke off -- looks like conductive plastic with pressure fitted tags.
When I tried fix it, it was showing good resistances. Even in circuit it shows good resistance. But it won't pass any current.
The test:
With a function generator outputting a sine wave at 60 Hz with 0.8 V amplitude, as simple DMM set to read VAC will read properly.
Since it is balanced in, a SE to balanced cable was used. The SE side connected to the function generator, the balanced plugged in to the buffer input.
Moving the XLR between channels, both outputs of the buffer were fine. However only one output of the buffer was functional.
On that channel, The input to the volume control was 0.8, the output at the wiper was zero.. the signal never even got to the DCB1.
Oh well.
I hear Khozmo makes a nice attentuator . and it is a ladder network, not conductive plastic.
This was a 10K pot. Given that the input is a powered buffer, perhaps there is a better choice of value now?
When I tried fix it, it was showing good resistances. Even in circuit it shows good resistance. But it won't pass any current.
The test:
With a function generator outputting a sine wave at 60 Hz with 0.8 V amplitude, as simple DMM set to read VAC will read properly.
Since it is balanced in, a SE to balanced cable was used. The SE side connected to the function generator, the balanced plugged in to the buffer input.
Moving the XLR between channels, both outputs of the buffer were fine. However only one output of the buffer was functional.
On that channel, The input to the volume control was 0.8, the output at the wiper was zero.. the signal never even got to the DCB1.
Oh well.
I hear Khozmo makes a nice attentuator . and it is a ladder network, not conductive plastic.
This was a 10K pot. Given that the input is a powered buffer, perhaps there is a better choice of value now?
The 2500 type TKD has screws at the back and can be opened to be better examined and maintained I think. See again about its wiper resistance and continuity. A 10K ladder has output impedance comparable to a 20K series (classic config) pot if I remember correctly. So get 10K when for ladder. They also make series step attenuators at Khozmo. In that case get their 25K one. Its cheaper too. Same mechanical reliability.
A lug to which you solder the wires too broke off. The way my unit is built, the inputs are in a lower enclosure, the board sits on top between two heatsinks.
I guess that when the heatsink/board was disconnected from the case, it slipped and tugged on the lug. The lug was pulled from the pcb that has grey conductive plastic on it taking some of the conductive "glue" with it.
I guess I could try wrapping a twist tie or cable tie around the broken joint and press it back together. Or just get some conductive glue....
It was intermittent. Now I know that was poor contact from the lug to pot. Nothing to do with wipers.....
I guess that when the heatsink/board was disconnected from the case, it slipped and tugged on the lug. The lug was pulled from the pcb that has grey conductive plastic on it taking some of the conductive "glue" with it.
I guess I could try wrapping a twist tie or cable tie around the broken joint and press it back together. Or just get some conductive glue....
It was intermittent. Now I know that was poor contact from the lug to pot. Nothing to do with wipers.....
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The TKD I was using was a 10K. I cannot get that side of it going -- it is now a mono pot.
It seems like the choices are 10K TKD, 10k ladder or 20K series.
Just to confirm, because it is stupidly expensive, if I was to buy a DACT CT2, it would be a series, so the 20K option would be the one?
It seems like the choices are 10K TKD, 10k ladder or 20K series.
Just to confirm, because it is stupidly expensive, if I was to buy a DACT CT2, it would be a series, so the 20K option would be the one?
I don't know about this rather economical EIZZ from China though. Seems well done mechanically but likely tube builds oriented by using carbon film resistors. Maybe its interesting: 25k series 24 positions from a European shop
They also offer the known economical ALLO from India. Although good electrically, surely rougher to handle: 10k ladder 24 positions
They also offer the known economical ALLO from India. Although good electrically, surely rougher to handle: 10k ladder 24 positions
Enough people are happy with the ALLO's precision SMD resistors ladder architecture for the price. Transparency should be fine if those surface resistors are thin film 25 ppm indeed. The mechanical feel and long term reliability should be so so though, its cheap. Valab style switch. Still doing the job. If stiff just use a larger knob.
I am happy with mine. Good feel and great sound. We will see how long it will last.
For $30 not bad.