As I said before
"And if something or someone gets a hiding for it, so be it.
As we want diy here that works without voodoo or snake oil involved, and gives full exposure, all the circuit diagrams for the claims made, and that has no ulterior motive attached to it for commercial gain.
And if claims are not laid out on the table, There's a place for that called "The Vendors Forum" not the DIY section
Cheers George
"And if something or someone gets a hiding for it, so be it.
As we want diy here that works without voodoo or snake oil involved, and gives full exposure, all the circuit diagrams for the claims made, and that has no ulterior motive attached to it for commercial gain.
And if claims are not laid out on the table, There's a place for that called "The Vendors Forum" not the DIY section
Cheers George
Diy is no place for false claims, snake oil, and fake circuits. Diy is supposed to be a place to share ideas and concepts. If my memory is correct George shared the original concept and made it available for others to try his circuit and I will add without financial gain. Its a shame that some seem to be in it for monitary gain from the uneducated general population.
I would remind you of post 1 where this thread started,
Between that post which established simply that a DIY forum member on his own behalf, wished to share his experience ... and now... we have witnessed FUD but worse, a orchestrated campaign of FUD, with highlights of :understanding fully, but humiliating me never the less, to repeat the connections of a audio purpose LDR ,using defamatory language, one post humiliating me, because I do not have a degree in electrical engineering, and generally the worst kind of disruptive childish forum conduct.
The conduct is being discussed at another forum here:
Comparison Lightspeed DIY LDR Pre VS Stereo Coffee DIY - Page 2 - DIY Audio Projects - StereoNET
It has seen valuable contributions over- run with yet more FUD.
I have also provided quotation from The Art of Sound Forum as to reasons why listening to audio equipment rather than measuring, solves the grey areas that present equipment cannot approach. I own and use an oscilloscope, a digital multimeter x 2 , as well as many reference books
The circuit provided as a DIY kit, I have developed, for obvious reasons shown in the paragraphs above, is not public domain.
Further I have made approach to tomchr on the forum as to cost of having the kit measured for distortion. I am doing my best to save for that cost.
I have however provided outline, of how it achieves the sound quality that it does. I have been honest and polite in all my posts, obeying forum conduct rules. I have offered twice to have the unit evaluated for its sound quality, and yet, I see no reply to that offer. 😕
I remain extremely proud, as do those using the 3 input kit, of its achievements to improve our audio experience.🙂
Chris, I think it would be best if you could move your commercial activities to Vendor's Bazaar or get a Vendor's Forum. That's why those forums exist.
While this is just my opinion, it's been brought up in this thread earlier.
While this is just my opinion, it's been brought up in this thread earlier.
Agreed, but this thread should be either closed, or moved to the "Vendors Forum"
Others that do diy here, some big hitters like Nelson Pass Soran Christensen ect ect, supply all circuit and parts details for the claims they make, many even supply the artwork for the diy pcb's and measurement graphs/figures, why this was allowed to go on for so long is beyond me.
Cheers George
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Where have you been here John is usually on the sidelines cheering them forward?
Just going to keep reposting Neil from here on out as there’s nothing that hasn’t been said, just some who refuse to acknowledge what has already been said.
Feels a bit like the old Lemmings video game.
Didn’t we go over the “further reviews or anecdotal reports mean absolutely zero to me” thing?
We can go on forever like this, but I will not acquiesce until test data of Chris’ preamp is published here, period.
If he is a capable engineer he can do it himself and send a unit to another here for verification, no need for Tomchr and $$$$.
Reviews I’m not wholly against. I’m against one without the other.
I said it’s the same designer, Chris. Presumably the same concept. I imagine he didn’t “design” it for free. Sorry, I don’t know their books and don’t know their arrangement.
No I should not post my own data because that means I’d have to buy one or build from scratch something I am extremely certain is a complete waste of money.
The burden of proof to provide data is on Chris, who made it.
Why he is unable to provide verifiable test data on his own product raises a multitude of other questions, including his general competence as a designer / engineer.
This is routine and is found all over diyaudio by those not just selling commercial products, but doing group buys or just to verify their own project.
If he did not make claims about it’s quality, no one would be asking him to provide supporting data.
Claims such as these by Chris on his website are extremely suspect in the absence of any test measurements whatsoever. Doubly so with schematics that have been examined by engineers with industry background, advanced education, etc. who suggest they basically resemble the output of a random schematic generating program.
“You could spend $10,000 on a preamp and still not get as good audio as this kit delivers, in fact we are certain.”
“It doesn't get any better !”
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It doesn't amplify anything therefore it isn't a preamp.
The word preamp can mean two things: a) the preamplifier circuit within any device b) a dedicated external device containing such a circuit. The purpose of a preamp is to amplify low level signals to line level, i.e. the “standard” operating level of your recording gear or other audio gear.
There is no preamplification circuit present in the optocoupler voltage divider therefore the term simply doesn't fit. Does it amplify? No, the signal isn't changed. In other words its a simple glorified volume control pot without a wiper.
There is no gain? Or even a buffer?
Then no it’s not a preamp. It’s an attenuator (volume control).
What downstream equipment are the staunch LDR believers using with it?
Then no it’s not a preamp. It’s an attenuator (volume control).
What downstream equipment are the staunch LDR believers using with it?
Why I don't trust the ear as much as I trust old fashoned instrumentation.
Probably 15 years ago I had several gentlemen drive to pick up some gear I was selling. I set it up in the garage to demo it. They wanted to have me do some tube rolling so I ran a number of different tubes thru the line stage they were interested in. Several times I used the same tube and simply tweeked the balance slightly. Their assessment was that the sound stage had more depth now and was spread out more. This was because I had put the notion into their head that this is what was going to happen. The mind if a funny thing.
If you measured a sample signal from a source it would be the same as what was coming out of the optocoupler voltage divider. I've already conducted tests and plots of a sample signal and the same signal as it came out of a standard Allen Bradley sealed control/pot. Its a passive device its not a preamp its a simple voltage divider used to control the audio level. As I mentioned and referenced a dictionary definition its not a preamp as it contains no electronics in the signal path.
There is most definately going to be a different sonic from the actual preamp they were using before simply because its sonic signature is gone.
Probably 15 years ago I had several gentlemen drive to pick up some gear I was selling. I set it up in the garage to demo it. They wanted to have me do some tube rolling so I ran a number of different tubes thru the line stage they were interested in. Several times I used the same tube and simply tweeked the balance slightly. Their assessment was that the sound stage had more depth now and was spread out more. This was because I had put the notion into their head that this is what was going to happen. The mind if a funny thing.
If you measured a sample signal from a source it would be the same as what was coming out of the optocoupler voltage divider. I've already conducted tests and plots of a sample signal and the same signal as it came out of a standard Allen Bradley sealed control/pot. Its a passive device its not a preamp its a simple voltage divider used to control the audio level. As I mentioned and referenced a dictionary definition its not a preamp as it contains no electronics in the signal path.
There is most definately going to be a different sonic from the actual preamp they were using before simply because its sonic signature is gone.
Nelson Pass designed the B1 which does contain a buffer and I believe it has 10db of gain. Others some have actually made an honest to goodness preamp with a preamp stage.
It is not necessary with a lot of audio gear to have a gain stage. most CD players will do a minimum of 1 volt peak to peak some will do 2 volts or more.
Example:
I have so much gain in any of my tube power amplifiers that I've barely turned the control pot. The SE amplifiers I have recently built will provide room filling volume simply off a tape deck/R-to-R, or CD.
It can be tested simply by inputting a signal from your sine wave generator and measuring it on your scope or RMS volt meter. Passive will result in the same level coming out of the generator and the volume control/voltage splitter. A true preamp and some buffer stages will result in more out than what has gone into it.
Preamps and buffers can and do for the most part help to color the signal and this is why the "difference in so called increased bass and for that matter midrange and hi frequency" might be heard when they are replaced with a passive device.
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Yes of course that is true and I was well aware of that before you came along. Nevertheless, the term "passive preamp" is in common use, even if incorrect in many circumstances.
Neil's lecture is a wonderful insight into the human mind in theology that I hadn't seen. People should watch it.
The substance of Neil's lecture is very general and could apply to all audio equipment including the LightSpeed, StereoCoffee. You are also casting doubts about the reason customers prefer LDR attenuators over other audio equipment like switched attenuators or pots.
1. Have you seen Lightspeed data? Yes or No.
2. What type of data did the engineers provide?
You didn't bother stating their qualifications.
3. What methodology did you use to analyse the data and what conclusion did you reach?
I currently have a DIY version of Lightspeed and I was very impressed with it but technology evolves over time an I prefer StereoCoffee because TO ME it is audibly better.
4. Have you heard a LightSpeed. Yes or No.
5. Have you heard a StereoCoffee? Yes or No.
6. Who are the nameless engineers who have examined StereoCoffee without having one, let alone the current model?
I almost unbelievable how someone with an an undisclosed advanced education background can analyse the performance of electronic equipment and provide meaningful data without having having it on the bench and measuring it.
Wil you will say the information is confidential and the people don't want their names published?
7. Please disclose what preamplifier you use or do you have an integrated amplifier?
8. What are YOUR own *technical qualifications in the audio industry?
*After all this is a DIY audio forum and people are interested.
As you know, I have challenged you in a previous post with similar question. Why didn't you didn't you provide the information?
You keep asking for data from Chris but you have never provided any against the StereoCoffee. Not even any data from George which I'm sure other members would like to see. How could you compare data for StereoCoffee with LightSpeed without that information?
For the record, StereoCoffee consists of two modules that a DIY customer assembles. It is a kit not a plug and play product like LightSpeed.
FYI. Your comment about preferring the JAVA casing suggests you are comparing it to the StereoCoffee. StereoCoffee does not have a casing but LightSpeed does. So what are you saying?
Will you supply this data critical please?
Please don't cherry pick this post and not answer these very basic questions. An honest reply could give you more credibility.
I'm sure other members of this forum will be interested.
Once more:
Chris sells a product
Chris makes exceptional claims about this product
This product has been repeatedly questioned by those who can interpret the schematic
Ethical issues have been raised on his marketing and forum behavior
The burden of proof is on Chris to substantiate his claims with measurable test data.
Anecdotal evidence is insufficient as a sole source of information to substantiate claims on a product which operates within the realm of science
Chris has provided a sum total of zero measurement evidence to support his claims or even evidence that his device functions properly
The lack of this evidence is concerning to many.
In order to put this matter to rest simply and quickly, chris can provide measurement data.
A sufficient measurement battery takes less than a day to accomplish.
Chris sells a product
Chris makes exceptional claims about this product
This product has been repeatedly questioned by those who can interpret the schematic
Ethical issues have been raised on his marketing and forum behavior
The burden of proof is on Chris to substantiate his claims with measurable test data.
Anecdotal evidence is insufficient as a sole source of information to substantiate claims on a product which operates within the realm of science
Chris has provided a sum total of zero measurement evidence to support his claims or even evidence that his device functions properly
The lack of this evidence is concerning to many.
In order to put this matter to rest simply and quickly, chris can provide measurement data.
A sufficient measurement battery takes less than a day to accomplish.
Well why don't you hear it for yourself, and if you be so kind then publish the findings here. There is evidence in my seller rating - evidence at many forums, evidence at many blog sites to the contrary .
If one of the many members here wishes to measure the distortion component - if any and do so either free or very low in cost, and publish that data here I would be happy to submit a kit or built unit which as a way of thanks they could then keep.
I would prefer that such measurement be done by one of the senior members such as Nelson Pass, Tom (tomchr ) or John Curl. I will send each a PM, beginning with Nelson.
If one of the many members here wishes to measure the distortion component - if any and do so either free or very low in cost, and publish that data here I would be happy to submit a kit or built unit which as a way of thanks they could then keep.
I would prefer that such measurement be done by one of the senior members such as Nelson Pass, Tom (tomchr ) or John Curl. I will send each a PM, beginning with Nelson.
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