john65b said:
Hi John;
Power supply and volume pot are in an ugly small box. I also use dual 1k pot for balance. Connection is for Ground, shunt LDR and Series LDR ( Left, Right).
Vincent
May I ask if all the devices with SR2 LDRs are MKII models ?
Secondly, if the load impedance is less than 100 k, what happens ? Is there is no more than insertion losses, how do you compute them ?
Thanks,
Secondly, if the load impedance is less than 100 k, what happens ? Is there is no more than insertion losses, how do you compute them ?
Thanks,
georgehifi said:
Tried the linear as opposed to the SMPS for the initial 12v supply, and it still sounds fantastic. Problem is though, can't tell if it's better than the SMPS because I didn't do a head to head and to be honest am a bit lazy to do a direct comparison....
Have yet to try some bypass caps on the LDRS though... welcome any suggestions on values -- have everything from 150uf to 0.1uf in my modest parts bin...
here my LED/LDR solution.
it's a fully Preamplifier with some GAIN, powered by two 12V SLA battery.
R45 is a LED/LDR, R44 a resistor (series configuration).
I sacrificed regulation linearity in favor of harmonic distorsion, all is controlled with a remote by a commercial (ebay) PCB.
marzio
it's a fully Preamplifier with some GAIN, powered by two 12V SLA battery.
R45 is a LED/LDR, R44 a resistor (series configuration).
I sacrificed regulation linearity in favor of harmonic distorsion, all is controlled with a remote by a commercial (ebay) PCB.
marzio
LDR bypass caps
Tried some bypass caps last night on the legs of the LDRs (PSU side) as described in prior posts:
Vishay MKP1837 0.1uf 160v
Wima 0.22uf (the little red ones)
Black Gate NH 150uf 350v (a bit cumbersome for this circuit)
Elna Silmic II 1000uf 16v
Elna Silmic II 1000uf 16v + Vishay MKP1837 0.1uf
Whether or not they changed it for the better I can;t tell. Problem is I'm terrible at evaluating incremental improvements... and wouldn't trust my ears and brain to be immune to placebo, given that there was a five minute listening gap between each cap... none of them seemed to ruin anything. Still, I thought that perhaps the 1000uf bypassed with the 0.1uf may have sounded slightly better... so all subjective and I have no measuring equipment...
I did notice a difference between using an SMPS and linear supply for the 12v part of the PSU, however (the linear being better). And of course a very clear difference between the lightspeed and my alps pots. Maybe I should try and train my ears a bit more for the tweaking.
Would be nice if anyone with thoughts on caps could share their findings... 🙂
Tried some bypass caps last night on the legs of the LDRs (PSU side) as described in prior posts:
Vishay MKP1837 0.1uf 160v
Wima 0.22uf (the little red ones)
Black Gate NH 150uf 350v (a bit cumbersome for this circuit)
Elna Silmic II 1000uf 16v
Elna Silmic II 1000uf 16v + Vishay MKP1837 0.1uf
Whether or not they changed it for the better I can;t tell. Problem is I'm terrible at evaluating incremental improvements... and wouldn't trust my ears and brain to be immune to placebo, given that there was a five minute listening gap between each cap... none of them seemed to ruin anything. Still, I thought that perhaps the 1000uf bypassed with the 0.1uf may have sounded slightly better... so all subjective and I have no measuring equipment...
I did notice a difference between using an SMPS and linear supply for the 12v part of the PSU, however (the linear being better). And of course a very clear difference between the lightspeed and my alps pots. Maybe I should try and train my ears a bit more for the tweaking.
Would be nice if anyone with thoughts on caps could share their findings... 🙂
jameshillj said:
Hi James
yes, that would be great because I am just a breadboard and veroboard guy and not a PCB layouter.
@ssmith
I don't think that anyone of us can hear a sonic difference between a Black Gate 150µF and a Elna 1000µF at the position you used it. 😉 Don't visit the audio doctor!
The difference between SMPS and linear PS is more obvious.
Tolu said:
That's a relief, thought I had cloth ears and may need to see one of the local ear cleaners..
Thomas system pcb
I use the old Protel system which works okay and apparently can be converted to other programs.
If you send me the circuit with any proposed variations, extras, etc with the power supplies and I'll put it together for your perusal, no problems.
... Jh
I use the old Protel system which works okay and apparently can be converted to other programs.
If you send me the circuit with any proposed variations, extras, etc with the power supplies and I'll put it together for your perusal, no problems.
... Jh
Lightspeed Attenuators
Just discovered this thread. Are these still available for purchase and if so how can I get them. Thanks in advance.
Just discovered this thread. Are these still available for purchase and if so how can I get them. Thanks in advance.
Re: Lightspeed Attenuators
Send me a PM with your email, as your PM is locked and I'll email you all the details, info, history and pics.
Cheers George
clio09 said:
Send me a PM with your email, as your PM is locked and I'll email you all the details, info, history and pics.
Cheers George
Since I'm still new here my account does not allow me to send PMs. Hopefully that will change shortly as I post a bit more. As soon as I can I will PM you. Thanks
possible Shunt Reg for Lightspeed -> Group buy info!
Hello Guys,
in the NS10 Clone Thread....the guys started a group buy wiki for the Toole Shunt Reg PCBs......a very nice shunt regulator from CeToole. Its working with 18-24V.....and Toole did post a Spice schematic for 3.3-5V:
http://www.diyaudio.com/forums/showthread.php?postid=1676965#post1676965
So......the Toole Shunt Reg is tweakable for 5V Operation....sounds nice for me! I will try it with my upcoming Lightspeed mk2!
The Wiki for the group buy is here:
Toole Shunt Reg Group Buy Wiki
Pictures of the PCB Set:
Just as information as a possible Reg solution for Lightspeed!
cya
Alan
Hello Guys,
in the NS10 Clone Thread....the guys started a group buy wiki for the Toole Shunt Reg PCBs......a very nice shunt regulator from CeToole. Its working with 18-24V.....and Toole did post a Spice schematic for 3.3-5V:
http://www.diyaudio.com/forums/showthread.php?postid=1676965#post1676965
So......the Toole Shunt Reg is tweakable for 5V Operation....sounds nice for me! I will try it with my upcoming Lightspeed mk2!
The Wiki for the group buy is here:
Toole Shunt Reg Group Buy Wiki
Pictures of the PCB Set:
An externally hosted image should be here but it was not working when we last tested it.
Just as information as a possible Reg solution for Lightspeed!
cya
Alan
another Lightspeed
tnx George 😉 for popularization of concept
http://www.diyaudio.com/forums/showthread.php?postid=1675963#post1675963
tnx George 😉 for popularization of concept
http://www.diyaudio.com/forums/showthread.php?postid=1675963#post1675963
Re: another Lightspeed
No problems, thanx.
I don't want to rain on your parade, but I wish you all the luck getting channel tracking and balance using balanced output, I know it's almost impossible, been there done that.
Also you may want to reconsider the use of the NSL-32SR3S as with a spread of 60ohms to 25mohms this will be a major headache, as the spread makes it even more difficult, the NSL-32SR2S is only 40ohms to 1mohm spread and this was already a chore to balance, even in single ended mode, let alone balanced. Also the NSL-32SR3S minimum volume will not be low enough for a lot of people being 60 ohms.
To all members remember these things need to be built tested and debuged before you good people start spending your money.
Cheers George
Zen Mod said:
No problems, thanx.
I don't want to rain on your parade, but I wish you all the luck getting channel tracking and balance using balanced output, I know it's almost impossible, been there done that.
Also you may want to reconsider the use of the NSL-32SR3S as with a spread of 60ohms to 25mohms this will be a major headache, as the spread makes it even more difficult, the NSL-32SR2S is only 40ohms to 1mohm spread and this was already a chore to balance, even in single ended mode, let alone balanced. Also the NSL-32SR3S minimum volume will not be low enough for a lot of people being 60 ohms.
To all members remember these things need to be built tested and debuged before you good people start spending your money.
Cheers George
Re: Re: another Lightspeed
tnx George ;
anyway - intention of our little project is to made it and try ;
some tests were already made , general concept is proofed , and changing LDR type is easiest thing , if these aren't up to task
georgehifi said:
tnx George ;
anyway - intention of our little project is to made it and try ;
some tests were already made , general concept is proofed , and changing LDR type is easiest thing , if these aren't up to task
Re: Re: Re: another Lightspeed
Glad for the clarification, still even using the better NSL-32SR2S you will reduce the problem of minimum volume range.
But the matching for the balance/tracking of 2 x the amount of NSL-32SR2S needed for balanced mode has not been addressed, as the tracking of a stereo balanced mode Lightspeed output has 4 x the matching problems of a single ended mode.
Hence to get that many for a good balance/tracking you would need something in the order of 30-40 x NSL-32SR2S to ferret out enough for a balanced output, trust me, I've been there done that over the 30 odd years of doing Lightspeed Attenuators.
The only way to get that many to track and be in balance has been discussed in these pages back a few months, using digital controlled tracking sensors that will keep everything tracking and balanced, but it is very complex and not for the faint hearted.
Cheers George
Zen Mod said:
Glad for the clarification, still even using the better NSL-32SR2S you will reduce the problem of minimum volume range.
But the matching for the balance/tracking of 2 x the amount of NSL-32SR2S needed for balanced mode has not been addressed, as the tracking of a stereo balanced mode Lightspeed output has 4 x the matching problems of a single ended mode.
Hence to get that many for a good balance/tracking you would need something in the order of 30-40 x NSL-32SR2S to ferret out enough for a balanced output, trust me, I've been there done that over the 30 odd years of doing Lightspeed Attenuators.
The only way to get that many to track and be in balance has been discussed in these pages back a few months, using digital controlled tracking sensors that will keep everything tracking and balanced, but it is very complex and not for the faint hearted.
Cheers George
Any advice for caps across the LDRs?
I have Sanyo Oscon SC 10uF and 100uF left over.......did used in a DAC circuit but dont have any experience in analog circuits.
Any experiences with Oscon Caps?
I have also Roderstein 47uF MKP 1837......overkill and unusable?
I am waiting for my PCB for my Lightspeed....so I can not test for myself and hope for advice from you all!
Thanks
Alan
I have Sanyo Oscon SC 10uF and 100uF left over.......did used in a DAC circuit but dont have any experience in analog circuits.
Any experiences with Oscon Caps?
I have also Roderstein 47uF MKP 1837......overkill and unusable?
I am waiting for my PCB for my Lightspeed....so I can not test for myself and hope for advice from you all!
Thanks
Alan