Bruno's RCA to XLR drawing looks just like 'tomchr' drawing.
http://www.diyaudio.com/forums/vend...er-achieving-0-0004-thd-n-20.html#post4154946
http://www.diyaudio.com/forums/vend...er-achieving-0-0004-thd-n-20.html#post4154946
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I see a difference.
Tom's has a connection from Shield to Signal Return at the Source.
Bruno's has a connection from Shield and Signal Return to Chassis at the Source.
That seems quite fundamental to me.
Planet IX, what X2Y library are you using?
The one I work with produces almost perfect gerber results, but somewhat misbehaves in the schematic editor...
Thanks,
Sebastian.
PS: Also, your differential signal pairs seem to be melting into a single copper strip.
I made the symbol and footprint by myself, since I did not find any useful library.
Yes the signal-pairs are pretty close to each other. It is still possible for the board production but it may generate some extra costs.
When it comes to production I possibly will change that...
Regards, Boris
So if the cable is a Shielded Twisted Pair and the cable connector is a RCA plug, just how would they be different?
I don't think the Source equipment Chassis should be connected to the Signal Return between the Source and the Receiver.
Look at just about every writers' advice.
Isolate the RCA/Phono from the Chassis. This is just about universal.
I can't understand why B.Putzeys has connected the Enclosing Chassis to the Signal line.
Look at just about every writers' advice.
Isolate the RCA/Phono from the Chassis. This is just about universal.
I can't understand why B.Putzeys has connected the Enclosing Chassis to the Signal line.
a] You should buy it, it and 6 other great papers, total of about 85 pages. The US price is $15 shipped to your door, I would think that the UK price is also reasonable.
b] Just do a search for: (it's out there somewhere)
"Noise Susceptibility in Analog and Digital Signal Processing Systems"
c] It's about all shields being connected to the chassis.
b] Just do a search for: (it's out there somewhere)
"Noise Susceptibility in Analog and Digital Signal Processing Systems"
c] It's about all shields being connected to the chassis.
I am aware of the later Whitlock version.
http://www.rane.com/note110.html
Pin 1 Problem
http://www.prosoundweb.com/article/finding_problems_in_balanced_audio_equipment_interfaces/
He and many others all tell us repeatedly about the proper way to wire pin1.
All consistently tells not to wire Pin1 to audio ground.
Shield goes to Pin1 Pin 1 goes to Chassis.
Signals go to the audio connections, not to Chassis.
That's why I can't understand B.Putzeys diagram that does show Signal return going to chassis.
http://www.rane.com/note110.html
Pin 1 Problem
http://www.prosoundweb.com/article/finding_problems_in_balanced_audio_equipment_interfaces/
He and many others all tell us repeatedly about the proper way to wire pin1.
All consistently tells not to wire Pin1 to audio ground.
Shield goes to Pin1 Pin 1 goes to Chassis.
Signals go to the audio connections, not to Chassis.
That's why I can't understand B.Putzeys diagram that does show Signal return going to chassis.
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Many thanks Jan!
It took me a while, but today I finally found some time to make my way through all the Eurocircuits options and offerings
I would like to go for the RF pool offering, either Isola I-TERA at pooling prices or Rogers 4000 series non-pooled (need to further get into the details). I would prefer Rogers 4000, recommended by Rogers for power amplifiers here with interesting additional information here.
Should work price-wise (will come up with calculation shortly, once I understand all these parameters...).
What do we all think of going RF PCB (Isola/Rogers) please? Overkill, useful, nonsense, ideal?
If Eurocircuits produced the original board for Linear Audio or Bruno, whoever organised the original 'free' board. Would they not have the details still on file ?
Assuming there is no IP being breached.
If 1000 of these boards were distributed before, then why is there so little feedback on the perfomance of the Pre. I wonder ?
I have e#mailed Hans Polak about the boards for his Volume control Mod.
He says he has none left, but it might be worthwhile to ask him if we could get some made.
It seems like a better idea than infinite volume, and also Bruno's notes on vol. control sensitivity at low level.
I wonder though if it has any implications for SQ.
Assuming there is no IP being breached.
If 1000 of these boards were distributed before, then why is there so little feedback on the perfomance of the Pre. I wonder ?
I have e#mailed Hans Polak about the boards for his Volume control Mod.
He says he has none left, but it might be worthwhile to ask him if we could get some made.
It seems like a better idea than infinite volume, and also Bruno's notes on vol. control sensitivity at low level.
I wonder though if it has any implications for SQ.
Jan (aka jan.didden) had produced the first run of 1,000 boards through Eurocircuits. I have the Gerbers, they are available from Linear Audio in the Downloads section here: Downloads | Linear Audio
True. As has been mused before, unfortunately quite a few of them unfortunately have ended up as shelveware or are still awaiting their build.
I have two more measurements from Hans Polak, confirming what an excellent preamp design this is, will post them later today.
I appreciate adding another option probably complicates matters, but a few months ago, I was in touch with a small UK company (Quick-circuits) who do very high quality PCB assembly. They specialise in surface mount and aren't too keen on through hole as it's a manual labour (in other words expensive in the UK), but I could enquire as to having a batch of 50 bare and assembled PCBs if of interest.
They did quote me for an assembled PCB of similar complexity and I was pleasantly surprised by the cost (around €20 per board assembled) although it was for simple / cheap components.
They did quote me for an assembled PCB of similar complexity and I was pleasantly surprised by the cost (around €20 per board assembled) although it was for simple / cheap components.
Hello community, I would like to ask for some information to modify the circuit pre.
1- I would eliminate the power supply because I have at home two 12V 7Ah batteries that will connect in series and the central +/- I connect it to ground. it's correct?
2- I would leave the pot 10k circuit without digital volume, but avoid the situational infinite gain while avoiding damage to the speakers and amplifier. What should I connect and where? I sound degraded?
Thank you all.
Alessandro
1- I would eliminate the power supply because I have at home two 12V 7Ah batteries that will connect in series and the central +/- I connect it to ground. it's correct?
2- I would leave the pot 10k circuit without digital volume, but avoid the situational infinite gain while avoiding damage to the speakers and amplifier. What should I connect and where? I sound degraded?
Thank you all.
Alessandro