Lightspeed Attenuator a new passive preamp - Page 394 - diyAudio
Go Back   Home > Forums > Source & Line > Analog Line Level

Analog Line Level Preamplifiers , Passive Pre-amps, Crossovers, etc.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 22nd January 2011, 06:57 PM   #3931
udailey is online now udailey  United States
diyAudio Member
 
Join Date: Mar 2008
It is expensive and the 2sj74 and 2sk170 are a guarantee. I dont blame you. Glad you are enjoying George's creation and happy I could help.
__________________
purchase LDRs anytime Also try my Resistor Replacers or LDR based Input Selector Email me. diyldr@gmail.com
  Reply With Quote
Old 23rd January 2011, 10:19 PM   #3932
diyAudio Member
 
georgehifi's Avatar
 
Join Date: Sep 2003
Location: Manly Australia (Jewel of the Pacific)
Send a message via MSN to georgehifi
Here's an interesting snippet from the latest Stereophile review of the DCS Debussy Dac which has volume control in the digital domain. Yet two stage adjustable analogue level output stage 2v or 6v, this means you can use it straight into a poweramp and only use the top 25% of the digital volume control, this way you should not be "bit striping".

Sterophile Quote: The differences in sound between the Debussy into a preamplifier and the Debussy directly driving a power amplifier will depend on the preamp's transparency, dynamic capabilities, and overall quality. Sending signals directly to my Musical Fidelity Titan amp from the Debussy or through my reference preamp, a darTZeel NHB-18NS, I heard minimal differences. Given the darTZeel's price of $29,500, that's what you should expect. :Stereophile Quote

Guess what the Dartzeel uses as a volume control? you guessed it. A Lightspeed setup, they tried to patent when they first released it but I quickly put a stop to it showing proof to the patent offices in Eu and USA that I first did the LDR volume control back in early 1974.

Quote from the Stereophile Review of the darTZeel NHB-18NS
"For the first time in all audio history," said Delétraz, "the signal path does not pass through any physical switch, relay, or even transistor switch." Instead, inputs are enabled or disabled using electro-optical analog components. Because there is no physical input switch or FET-based analog switch, there is no "diode effect," either electrical or chemical (electrovalence differential), to alter the signal, he explained in an e-mail. Quote



Cheers George
__________________
Avatar : Production Lightspeed Attenuator
www.lightspeedattenuator.com
  Reply With Quote
Old 27th January 2011, 09:55 PM   #3933
ua100k is offline ua100k  United States
diyAudio Member
 
ua100k's Avatar
 
Join Date: Dec 2009
Location: Bernardsville, NJ
Quote:
Originally Posted by georgehifi View Post
A Lightspeed setup, they tried to patent when they first released it but I quickly put a stop to it showing proof to the patent offices in Eu and USA that I first did the LDR volume control back in early 1974.
George,
Curious, how did you know they were about to patent this idea. Great that you caught it!!
  Reply With Quote
Old 28th January 2011, 03:11 AM   #3934
diyAudio Member
 
georgehifi's Avatar
 
Join Date: Sep 2003
Location: Manly Australia (Jewel of the Pacific)
Send a message via MSN to georgehifi
In the 6 Moons review. The interview with Herve is after the review of the NHB-18NS.
6moons audio reviews: darTZeel NHB-18NS

Quote:
Q: What is wrong with conventional volume controls?
A: You lose something. I use a system that varies resistance with light. However, until all the patents are in place, I would prefer not to specify the details.
Quote:

Cheers George
__________________
Avatar : Production Lightspeed Attenuator
www.lightspeedattenuator.com
  Reply With Quote
Old 28th January 2011, 11:39 AM   #3935
ua100k is offline ua100k  United States
diyAudio Member
 
ua100k's Avatar
 
Join Date: Dec 2009
Location: Bernardsville, NJ
Great catch. Thank you for doing that and taking care of the community. I see they do not use that statement on they web site now.
  Reply With Quote
Old 28th January 2011, 06:51 PM   #3936
diyAudio Member
 
Join Date: Nov 2007
Location: Scotland
I see that the $23,500 darTZeel NHB-18NS has "a Pleasure control" and an "Enjoyment Source". Is it an amplifier or an upmarket sex toy?

My little Lightspeed is starting to look a bit dull. Can I call it an "Optical Relief"?
  Reply With Quote
Old 28th January 2011, 08:18 PM   #3937
diyAudio Member
 
sepolansky's Avatar
 
Join Date: Nov 2007
Location: Maryland
Quote:
Originally Posted by Ryelands View Post
I see that the $23,500 darTZeel NHB-18NS has "a Pleasure control" and an "Enjoyment Source". Is it an amplifier or an upmarket sex toy?

My little Lightspeed is starting to look a bit dull. Can I call it an "Optical Relief"?
Is the darTZeel push-pull?
  Reply With Quote
Old 28th January 2011, 08:37 PM   #3938
diyAudio Member
 
Join Date: Jun 2008
....and does it suffer midrange suck out ?
  Reply With Quote
Old 29th January 2011, 06:33 PM   #3939
diyAudio Member
 
Join Date: Sep 2009
I have a quick newbie question. On the 100k volume control dual potentiometer, what is the purpose of shorting pin 2 and 3 on one gang and pin 1 and 2 on the other gang? Can we just use the pin 2 on both gang, and leave pin 3 and pin 1 alone?
  Reply With Quote
Old 29th January 2011, 10:11 PM   #3940
diyAudio Member
 
Join Date: Sep 2009
Just finished building the Lightspeed kit I bought from udailey. Good news is it works! However the volume control is reversed somehow. The volume goes down when turned clockwise, and goes up when turned counter clockwise. Can I simply swap the leads going to main LDR and shunt LDR from the potentiometer?
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



New To Site? Need Help?

All times are GMT. The time now is 04:14 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2