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Old 23rd June 2007, 02:53 PM   #761
john65b is online now john65b  United States
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I could have swore it was an "100K Audio Taper" pot - which is a Log Pot correct?

If it is a Linear pot, I guess I can try a Law Fake 10K resistor across the wiper and ground on both gangs...

If all is well I may update to the single 100K log pot (so no chance of channel mismatch on pot side)
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Old 23rd June 2007, 05:51 PM   #762
john65b is online now john65b  United States
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OK, I confirmed that the Pot I am using is indeed a 100k Log pot.

I reconnected the pot so I am using just the one side of the Dual pot per last schematic and it works fine. I need to do some more critical listening and may have to recalibrate the channels since I changed things around a bit...so far looks/sounds promising...
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Old 25th June 2007, 08:52 PM   #763
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Default What do you guys make of this????

I don't know what to make of it, remember the Dartzel NHB-18NS preamp that I posted back on page 69, the designer Hervé Delétraz, where he stated that the reason for the great sound out of this pre was mainly due to the LDR (Lightspeed) volume control, well the links to this seem to have disappeard of Dartzel website.
http://www.dartzeel.com/pages_E/NHB18_info_E.html

And now Stereophile have released the review free to read on their website,
http://www.stereophile.com/solidpreamps/607dart/
but again no mention of the LDR (Lightspeed) volume control that I can see.

6 Moons review is still there
http://www.6moons.com/audioreviews/d...l2/preamp.html

I have also noticed that the so called patent application on the volume control still has not been lodged as Hervé Delétraz said in that interview he had made.

Cheers George
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Old 25th June 2007, 11:59 PM   #764
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I don't mean to be disparaging, but it seems to me that the Lightspeed is simply an implementation of the level control as seen on the Silonex website. Pretty much a copy of the series/shunt design that they suggest for their parts.

So OK you have been kind enough to draw our attention to how good the Silonex parts sound, but it does not seem as if you have come up with anything particularly original. OK so you say that you had been experimenting with LDRs for years, but as far as I am aware, so have other people. But the first version of the Lightspeed used a Silonex part, right?

So why the fuss about whether anyone else is using the same idea. Silonex surely want as many people as possible to use their parts in the way that they meant to be used. (I am thinking here of the comments about audio synthesis for example, or indeed, the Dartzel)

I know that this sort of thing is common in audiophile-land - after all, look at all the fuss made over the "gain clone" which after all is pretty much wiring up a chip according to the Nat Semi datasheet.
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Old 26th June 2007, 12:21 AM   #765
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Go back 35 years ago then you have when I started it, and not with Silonex parts, read the thread from the begining, and you will be better informed as to the history.
And the very first version (35 years ago) of the Lightspeed, I built out of cds cells I removed from light meters of old broken down cameras.


Cheers George
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Old 26th June 2007, 12:59 AM   #766
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George, yes I had read the whole thread. I noted that you say you have been doing this for a long time, and can prove it. (Care to prove it?)

You also mention that the first Lightspeed prototype is about 5 years old.

I also note that the very first post shows a circuit diagram lifted from the Silonex website.

Also I saw this:
Quote:
I have a small problem with Audio Synthesis for using the system and not disclosing it because they would know that Melos and I have done it, and probally want to be seen as innovators and not copiers of a new system, why else keep it quiet.And with Dartzeel trying to give the impression that they are innovators of this LDR system as well and giving the impression that they will get a patent for it.
How would Audio Synthesis have known that you were doing this?

It seems that there were people doing this before you were, even if you were doing this 35 years ago.

I very much doubt that Datzeel were hoping to get a patent for something that appears on Silonex's website. I think it's more likely that they were thinking of patenting some other aspect of their design.
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Old 26th June 2007, 01:42 AM   #767
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Haven't you got a life, here are some names, find out yourself.



No1: George Cronin Master violin teacher at the Conservatorium of Music Sydney

No2: Otto Major the only person who has been completely re-diaphraming/rebuilding Quad ESL57 since they were first released, recomended by the late Peter J. Walker

No3: Elson Silver Australia's primo Tube amp builder

No4: Christian Feillafe Australia first pure Class A stereo amp manufacture, also in partnership with Otto Major in the Quad 57 program

No5: Steven Dertatz my mentor from the age of 16 and Australia's and probably the world foremost authority on Photo Electronics

And a host of others which some are no longer with us



You realy don't do your homework before frothing forth.
Quote>I very much doubt that Datzeel were hoping to get a patent for something that appears on Silonex's website. I think it's more likely that they were thinking of patenting some other aspect of their design.<Quote

Herve Delaratz interview
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



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Old 26th June 2007, 01:49 AM   #768
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Haven't you got a life
Sounds like Ad Hominem to me
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Old 26th June 2007, 05:24 AM   #769
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Quote:
Originally posted by john65b
OK, I confirmed that the Pot I am using is indeed a 100k Log pot.

I reconnected the pot so I am using just the one side of the Dual pot per last schematic and it works fine. I need to do some more critical listening and may have to recalibrate the channels since I changed things around a bit...so far looks/sounds promising...

Hi John,

If you need any help, I have a circuit board design for you. The log pot is just a standard Radio Shack one and the 1k variable trimmers you can get there too. The 6th south store has em.

You will like these preamps with the proper amp.

Bear
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Old 26th June 2007, 05:55 AM   #770
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You realy (sic) don't do your homework before frothing forth.
The quote is from the interview that you just pointed out had been removed, right? Well that's why I could not check that out (as I failed to look that up when it was available).

OK so I went to the Dartzeel website. If you read about their preamp you find that there are many different aspects they claim make their device sound so good.

They claim that their various "circuits are patented", not specifically the volume control.

Now when it comes to the volume control they say:

Quote:
The sound signal is attenuated in a fully passive way, using special analog optical couplers controlled by a dedicated processor, providing a dynamic range of 96 dB, through 192 discrete steps of 0.5 dB.
So clearly they are using a similar thing to what you are. But whereas the Lightspeed is basically the design from the Silonex website, they have produced a design that uses a "dedicated processor" to produce a series of 192 steps providing a dynamic range of 9dB.

Given the problems that you have noted of getting these devices to match, I suspect that they may well have come up with a clever way of controlling these devices such that they (a) track together properly and (b) give a much larger dynamic range.

If they have, then this may well be worthy of a patent.

Hardly "not doing my homework". And btw, "frothing forth" is not what I was doing. I was commenting. That sort of language says a lot more about you than it does about me.
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