Lightspeed Attenuator

[jonners]

Thanks for that Richard. PM sent.

[snip]

I've been interested in trying George's Lightspeed Attenuators for a while http://members.optusnet.com.au/~georgehifi/ , details of the Lightspeed are on here http://www.diyaudio.com/forums/showt...194&highlight=

I like it, a somewhat simpler implementation than the Twisted Pear Joshua Tree and without the scare of EMI bleed from relays.

Obviously one could control it from any old motorised potentiometer yes?

//Jan

[leo]

Hi Jan,

I'd imagine a motorised pot could be added easy enough it would make a nice and convenient remote attenuator

[aquapiranha]

I looked at remote motorised pots for mine, but they are 9imo0 too expensive. An excellent idae though.

[jonners]

With the help of Tripmaster in importing a matched pair of LDRs (Thanks Richard ) I have upgraded my attenuator to the series+shunt version with pleasing results. It does seem to improve on the fixed resistor/shunt LDR version, as others have noted.
I'm using a motorised pot with it for remote control:http://cgi.ebay.co.uk/Remote-Volume-...#ht_3491wt_708
I see that Uriah now has a very good offer going: Board, components and matched LDRs for $30 delivered. You just need to add a 5V power supply and a 100k log pot. http://www.buildanamp.com/LDRs-for-L...RsBOARDKIT.htm

[24bit]

Hello gentleman,

I am sound engineer, and few months ago I've found accidentally info about LDR.
After some research it's definitely a 'must have' for me. I run a little home based mastering studio and I can call myself a talented sound engineer my diy skills regarding electronic are minimal...
I use at my place a tube power amp and passive PMC TB2.
LDR seems to me a perfect solution. I am after transparency in audio signal.

Therefore I am kindly asking users of this forum here, able to build/solder LDR att. (without remote) for me, and I am happy obviously to pay for such job.

Please help!

all the best

[Clive]

Have you looked at http://members.optusnet.com.au/~georgehifi/

Also in the UK Paul Hynes may build one for you (though his is remote controlled): http://www.audiocircle.com/index.php?topic=87969.0

Paul looks in here from time to time.

[Puffin]

With the help of Tripmaster in importing a matched pair of LDRs (Thanks Richard ) I have upgraded my attenuator to the series+shunt version with pleasing results. It does seem to improve on the fixed resistor/shunt LDR version, as others have noted.
I'm using a motorised pot with it for remote control:http://cgi.ebay.co.uk/Remote-Volume-...#ht_3491wt_708
I see that Uriah now has a very good offer going: Board, components and matched LDRs for $30 delivered. You just need to add a 5V power supply and a 100k log pot. http://www.buildanamp.com/LDRs-for-L...RsBOARDKIT.htm

Jonners. I have one of those ebay r/c pre-amps. I was not sure how to modify it for use with the L/Speed. I have another r/c Alps pot which I am using at the moment, but would be grateful to know how you did it.

Rob.

[24bit]

Have you looked at http://members.optusnet.com.au/~georgehifi/

Also in the UK Paul Hynes may build one for you (though his is remote controlled): http://www.audiocircle.com/index.php?topic=87969.0

Paul looks in here from time to time.

Thank you for reply,
I sent an email to George and awaiting for his answer, but for my knowledge he lives in Australia, so shipment could be pricey... Anyway I will try to find out all costs,
The other guy's LDR is with remote which I don't need,
so my offer is still actual for UK based DIY'ers,
come on lads!

all the best

[jonners]

Jonners. I have one of those ebay r/c pre-amps. I was not sure how to modify it for use with the L/Speed. I have another r/c Alps pot which I am using at the moment, but would be grateful to know how you did it.

Rob.

Rob -

You've already seen this via PM, but in case anyone else wants to know the answer some help can be found here: http://www.diyaudio.com/forums/group...ml#post2168298 (Though I saw this after I had found my own way of doing it, which was slightly different.)