Can anyone suggest some sort of a buffer that would split the signal out of a channel on a preamp into 3 feeds that would go to 3 amps?
Using a simple 3-way splitter cable results in horrible sound degradation, something is clearly needed to take care of impedance.
Not necessarily DIY, commercially available stuff would actually be preferred.
Transformer based devices are out of question.
Using a simple 3-way splitter cable results in horrible sound degradation, something is clearly needed to take care of impedance.
Not necessarily DIY, commercially available stuff would actually be preferred.
Transformer based devices are out of question.
Not sure what level of performance you need. Lot's of choices, search "audio distribution amp" either on Amazon or Parts Express.
Source is Bryston BP-26 preamp, intent was to drive a pair of 3 channel Bryston 6B amps, thus the need to split the signal 3 way.
As mentioned, using simple cable splitter the performance degradation is tremendous.
Same kind of degradation is observed no matter what kind of source is used, for example I also tried a multichannel DAC with digital volume control, so I had a chance to compare one to one connection without signal splitting (one output from DAC to one input on amp) and one to 3 connection with cable splitter (one DAC output to 3 inputs) and again the performance determination was enormous.
So clearly a buffer is needed to maintain impedance, and I am looking at best possible solution that will not impart any signature of its own).
As mentioned, using simple cable splitter the performance degradation is tremendous.
Same kind of degradation is observed no matter what kind of source is used, for example I also tried a multichannel DAC with digital volume control, so I had a chance to compare one to one connection without signal splitting (one output from DAC to one input on amp) and one to 3 connection with cable splitter (one DAC output to 3 inputs) and again the performance determination was enormous.
So clearly a buffer is needed to maintain impedance, and I am looking at best possible solution that will not impart any signature of its own).
The preamp manual claims to be able to output up to 15V into any load of 600 ohms or greater. That should be fine, although it also admits that the circuit is discrete so perhaps not as low an output impedance as an op-amp circuit.
The 6B manual indicates an input impedance of 50k.
That should all be fine. Direct connection should preserve the signal with no problems. Perhaps your units are faulty?
The 6B manual indicates an input impedance of 50k.
That should all be fine. Direct connection should preserve the signal with no problems. Perhaps your units are faulty?
buffer stage
IIU correctly you are wanting to split your left and right to drive three (each) amp inputs. If so the input impedance of the three 50k amp inputs in parallel works out to 16700 ohms. Even if you have extremely low output impedance from your preamp the frequency responce is going to be impacted. There are lots of choices, but the challenge is to get up to the performance level of your Bryston's.
I have used Kramer, CE labs, Audio Authority and RDL. You can check them all out at Markertek (no affiliation). I'd lean toward a Kramer or RDL product.
HTH
IIU correctly you are wanting to split your left and right to drive three (each) amp inputs. If so the input impedance of the three 50k amp inputs in parallel works out to 16700 ohms. Even if you have extremely low output impedance from your preamp the frequency responce is going to be impacted. There are lots of choices, but the challenge is to get up to the performance level of your Bryston's.
I have used Kramer, CE labs, Audio Authority and RDL. You can check them all out at Markertek (no affiliation). I'd lean toward a Kramer or RDL product.
HTH
A preamp that claims to be able to drive 600 ohms should have no difficulty driving 16700 ohms! Unless, of course, that 16700 ohms is highly non-linear - but in that case driving just one amp would be a (smaller) problem.
The only effect on frequency response would be a reduction in bass, if the preamp output cap is too small. But then it would already be far too small to drive 600 ohms.
Tell us more about this 'simple 3-way splitter cable'?
The only effect on frequency response would be a reduction in bass, if the preamp output cap is too small. But then it would already be far too small to drive 600 ohms.
Tell us more about this 'simple 3-way splitter cable'?
Perhaps you should ask Bryston why their preamp appears not to be able to meet its spec. 30ft of cable could give a capacitance of 1nF. Probably a bit high for many preamps, but Bryston claim theirs can drive 600 ohms. 1nF at 20kHz is 8k reactance, so small by comparison. Perhaps their output stage can't cope with a capacitive load and is verging on instability?
This is a 10 year old paper by Jim Brown on balanced splitters.
'Mic Splitters'
http://www.audiosystemsgroup.com/Mic_Splitters.pdf
'Mic Splitters'
http://www.audiosystemsgroup.com/Mic_Splitters.pdf
Hi,
We have tons of WSW 811453C (Siemens IA) modules, I would like to use some of them for splitting line and maybe instrument signals. Anyone knows output impedance?
I am sure they can drive 600 Ohms, they where also used for exactly this purpose in the internal distribution system of the ORF (Austrian Broadcasting), as far as I know.
But that seemed to have included an additional resistor network. I don't know if this makes sense.
I hope there is a way to get this to work without too much complication...
Interesting topic for studio owners!
Cheers
Richard
We have tons of WSW 811453C (Siemens IA) modules, I would like to use some of them for splitting line and maybe instrument signals. Anyone knows output impedance?
I am sure they can drive 600 Ohms, they where also used for exactly this purpose in the internal distribution system of the ORF (Austrian Broadcasting), as far as I know.
But that seemed to have included an additional resistor network. I don't know if this makes sense.
I hope there is a way to get this to work without too much complication...
Interesting topic for studio owners!
Cheers
Richard
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