View Full Version : LDR preamp build
Light Dependant Resistor
15-10-2018, 09:36
Hi
I am posting up this thread to show what is involved with building a LDR preamp into casework.
This first image shows the transformer a toroidal with AC secondaries 12v- 0v 12v- 0v awaiting wiring the blue primary wires to a IEC connector with integral fuse
the remote control regulator, remote control board, and new main board.
Further images and description as it proceeds.
Yes, I'm looking forward to this arriving...:)
Marco.
walpurgis
18-10-2018, 22:14
And I'm interested in hearing about that Marco. I've fancied trying one for a while.
Firebottle
19-10-2018, 09:03
I have just wired one into a supplied case for a member on here. It was very transparent.
It is Steve from Birmingham but can't recall his forum name.
I have the 2010 version. As Alan says very transparent. Just let's the music flow through.
Have ordered the latest version which according to Chris (LDR) will be more transparent. Also ordered the remote control. Hopefully I will be able to install the lot easily.
@marco you are in front of me in the queue. :)
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Lol... Just looking forward to hearing what it sounds like and comparing it with my Croft, then reviewing it for the forum.
The review be in-depth and 'professional', magazine stylee, in a way I haven't produced for a long time, with references to various music recordings and plenty of pics, so stay tuned!:cool:
Marco.
montesquieu
19-10-2018, 18:59
I have the 2010 version. As Alan says very transparent. Just let's the music flow through.
Have ordered the latest version which according to Chris (LDR) will be more transparent. Also ordered the remote control. Hopefully I will be able to install the lot easily.
@marco you are in front of me in the queue. :)
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Is that the one we tried at my place Edward?
Is that the one we tried at my place Edward?The very one.
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Light Dependant Resistor
27-10-2018, 10:41
Final audition of main board tonight external to case. Very pleased with how it is sounding.
Looking good Chris.
I hope I can drop the new board into my case "as is" and then later fiddle around with changing over to the remote control and multiple inputs.
Any ideas of timing when you will be sending things out?
E
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Light Dependant Resistor
27-10-2018, 11:18
Hi Edward
With your build you will need to change to cathode wiring. You presently have volume in the anodes
-the change is pretty easy. I will get boards to you as soon as I can.
Hi Edward
With your build you will need to change to cathode wiring. You presently have volume in the anodes
-the change is pretty easy. I will get boards to you as soon as I can.Cheers.
But Marco first. :)
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Light Dependant Resistor
04-11-2018, 01:24
Image shows looking inward to rear panel IEC fitting connected, and ground tabs of RCA's soldered to each RCA not just relying on metal to metal touching , awaiting wiring. 24529
Light Dependant Resistor
06-11-2018, 00:06
RCA signal wiring all done, anodes and cathodes too, and just the front panel wiring to anode switch
and remote control board to go. The rectifier and regulator for remote board tested this morning delivering 13.3v
is neatly under the main board. 24534
Sherwood
06-11-2018, 13:41
Hi Edward
With your build you will need to change to cathode wiring. You presently have volume in the anodes
-the change is pretty easy. I will get boards to you as soon as I can.
A growing problem for the NHS! :o
Light Dependant Resistor
07-11-2018, 05:25
Hi Geoff
The NSL32SR3 is an audio purpose encapsulated LDR, unlike the open face types used in street lamps and ovens
which I think you are confusing it with, shown here. https://www.kitronik.co.uk/blog/how-an-ldr-light-dependent-resistor-works/
that indeed have issues with the way they are used.
The NSL32SR3 with indifference is entirely harmless from any health concern because of the care taken with encapsulation.
The data sheet provides the audio purpose encapsulated devices specifications http://lunainc.com/wp-content/uploads/2016/06/NSL-32SR3.pdf
See the difference ?
Light Dependant Resistor
09-11-2018, 08:14
Image showing completed build. The switch used for the anode switching of series pairs was a fairly chunky type
using a ball bearing type race, so has feature of positioning the contact at its center of travel when the input is changed,
which is a little different to normal switches that have a dead sort of center contact.
The shafts of the input and switch and the remote board worked out well for their length, which required some additional drilling
to get the bodies of each as close to the front edges. Wiring between boards and signal wiring was done with enamel wire
throughout, which required testing with a multimeter for continuity.
Very happy with the end result and sounding very nice too.
Hi Chris,
Is that mine?:)
Marco.
A little bird informs me an LDR pre has landed and awaiting test and feedback here.
Hello Marco. :eyebrows:
Interesting to see how one of these compares to a UK-Legal Khozmo 'pot-in-a-box' of similar resistance value. Both are passive types I understand.
A little bird informs me an LDR pre has landed and awaiting test and feedback here.
Hello Marco. :eyebrows:
Yes, but unfortunately life is getting in the way! :doh::D
Hopefully, I'll get some time during the week to fire her up.
Marco.
I built one years ago and it is the best pre I have....IMO of course. Not using a Pre now....and that is even better.
I built one years ago and it is the best pre I have....IMO of course. Not using a Pre now....and that is even better.I have an LDR pre but with 8 year old boards. Am waiting for the new boards which the maker Chris says is is even better. The current one is very good. Detailed, transparent, uncolored and just lets the music flow.
How are you attenuating things?
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Bigman80
24-11-2018, 19:53
Interesting to see how one of these compares to a UK-Legal Khozmo 'pot-in-a-box' of similar resistance value. Both are passive types I understand.
What do you mean by "UK-Legal Khozmo" Dave?
What do you mean by "UK-Legal Khozmo" Dave?
Suspect it's a subtle reference to the legal RoHS status (in the EU, and hence the UK) of devices using cadmium sulphide.
Think it depends on the PPM as stated below. Looks like its permitted to have less than 100ppm...
.....
RoHS Restricted Substances
RoHS specifies maximum levels for the following 10 restricted materials. The first six applied to the original RoHS while the last four were added under RoHS 3.
Lead (Pb): < 1000 ppm
Lead is commonly used in the electrical and electronics industry in solder, lead-acid batteries, electronic components, cable sheathing and in the glass of cathode-ray tubes.
Mercury (Hg): < 100 ppm
Mercury is widely used metals in the production of electrical and electronic appliances and is concentrated in batteries, switches and thermostats, and fluorescent lamps.
Cadmium (Cd): < 100 ppm
Cadmium is used in electronic equipment, car batteries, and pigments.
Hexavalent Chromium (Cr VI) < 1000 ppm
While some forms of chromium are non-toxic, Chromium VI can produce toxic effects.
Polybrominated Biphenyls (PBB): 1000 ppm
These are flame retardants found in electronic and electrical appliances. They have been found in indoor dust and air through evaporation from plastics.
Polybrominated Diphenyl Ethers (PBDE): < 1000 ppm
These are also flame retardants found in electronic and electrical appliances. Combustion of printed wiring boards release toxic emissions.
Bis(2-Ethylhexyl) phthalate (DEHP): < 1000 ppm
These are used to soften PVC and vinyl insulation on electrical wires.
Benzyl butyl phthalate (BBP): < 1000 ppm
These are used to soften PVC and vinyl insulation on electrical wires.
Dibutyl phthalate (DBP): < 1000 ppm
These are used to soften PVC and vinyl insulation on electrical wires.
Diisobutyl phthalate (DIBP): < 1000 ppm
These are used to soften PVC and vinyl insulation on electrical wires.
I have an LDR pre but with 8 year old boards. Am waiting for the new boards which the maker Chris says is is even better. The current one is very good. Detailed, transparent, uncolored and just lets the music flow.
How are you attenuating things?
§
I built mine P2P with a schematic posted on Diyaudio. I always thought that the LDR's would have a finite life, but many years on they are still going. The 100k pot is (I have always understood, but someone might correct me) a voltage control. The design as many others has variable resistors to give some control over channel imbalance given the nature of LDR's. However I use 2 additional pots that give much greater control over balance and work to very good effect.
Bigman80
25-11-2018, 08:19
I don't think I am too worries about it. Legal or not, it sounds superb.
Bigman80
25-11-2018, 08:21
Looks like a really tidy build. Looking forward to reading the feedback.
Can it oust Marcos Croft pre?
Weee Neeeed a Baaake Offff !!! :ner::lol::ner::mental:
Weee Neeeed a Baaake Offff !!! :ner::lol::ner::mental:
We had one a while back https://theartofsound.net/forum/showthread.php?32677-Are-LDR-pres-the-ultimate-passive
Bigman80
25-11-2018, 09:31
Are we talking, DCB1 V LDR V CROFT V PASSIVE.
That's a decent lineup for a bakeoff.
It would appear that there are individuals with a history of intensity about building a system, now arrived at a position where they are settling on their choice of Pre amp devices.
There will be two versions of a DCB1, Macca will have a previous device he favoured.
Marcus has the Croft and a LDR.
When Marcus has evaluated the LDR, I am sure it would gather a wider interest, if a date was set, to let the devices be evaluated against each other.
As already stated, to move beyond such performance of a DCB1, much more monies would need to be parted with. It would be nice to see how the models as whole compare.
Are we talking, DCB1 V LDR V CROFT V PASSIVE.
That's a decent lineup for a bakeoff.
There was another bake off after that one I linked to that included Marco's Croft but I can't find it.
Should point out that Marco's Croft is heavily modified and has a power supply in a separate box that weighs as much as a small moon so it isn't like any Coft pre you can actually buy.
Bigman80
25-11-2018, 09:59
It would appear that there are individuals with a history of intensity about building a system, now arrived at a position where they are settling on their choice of Pre amp devices.
There will be two versions of a DCB1, Macca will have a previous device he favoured.
Marcus has the Croft and a LDR.
When Marcus has evaluated the LDR, I am sure it would gather a wider interest, if a date was set, to let the devices be evaluated against each other.
As already stated, to move beyond such performance of a DCB1, much more monies would need to be parted with. It would be nice to see how the models as whole compare.
Yes i agree.
Marco's Chroft is a CharismaX i believe and thats bar far the most expensive and heavily customised preamp here. I think a bakeoff is definitely in order and id be happy to bring my DCB1 Level 3 preamp if one were to happen.
Maybe I ought to hold off upgrading my LDR (2010 boards) so that can be compared to Marco's LDR (2018 boards)? Happy to mail it if I am unable to make it to a bake off.
I don't think I am too worries about it.
Me neither, despite the angst surrounding it from certain elderly members of 'care in the community';)
Marco.
Looks like a really tidy build. Looking forward to reading the feedback.
Can it oust Marcos Croft pre?
We'll arrange a bake-off in the New Year, which will both give me time to get a proper handle on what the LDR is doing, versus the Croft, and post an in-depth review of it (as promised) for the forum:)
Marco.
Looks like a really tidy build. Looking forward to reading the feedback.
Can it oust Marcos Croft pre?
I think it is highly unlikely because, at the end of the day, it is still a passive pre (or a unity gain buffer) and the Croft is an active pre-amp. If Marco prefers the way his active pre drives his power amps then no passive will better it. Detail, delicacy etc will be great and drive and dynamic contrast will not be as good.
Bigman80
25-11-2018, 11:08
I think it is highly unlikely because, at the end of the day, it is still a passive pre (or a unity gain buffer) and the Croft is an active pre-amp. If Marco prefers the way his active pre drives his power amps then no passive will better it. Detail, delicacy etc will be great and drive and dynamic contrast will not be as good.Yep, I agree with that. BUT what happens if he prefers the LDR!!!!!!
Bigman80
25-11-2018, 11:09
We'll arrange a bake-off in the New Year, which will both give me time to get a proper handle on what the LDR is doing, versus the Croft, and post an in-depth review of it (as promised) for the forum:)
Marco.Sounds good. The DCB1 might also be built by then [emoji23][emoji23]
Bigman80
25-11-2018, 11:09
Me neither, despite the angst surrounding it from certain elderly members of 'care in the community';)
Marco.[emoji1787][emoji1787]
Me neither, despite the angst surrounding it from certain elderly members of 'care in the community';)
Marco.
Health & Safety seems to be taken lightly. I would be asking how much cadmium is actually in on of these pre's.
Sorry if this puts a spanner in the works.
Health & Safety seems to be taken lightly. I would be asking how much cadmium is actually in on of these pre's.
Sorry if this puts a spanner in the works.
Not really. You would have to eat the LDRs for it to be potentially harmful. Not that eating any type of resistor is a good thing to do for your health.
Health & Safety seems to be taken lightly.
It really isn’t. However, some like to spread FUD, presumably in an attempt to deflect criticism from their own woeful lack of attention to health and safety - like no output protection in their amps (specifically, the ones you use).
A very cursory Google shows that cadmium is present in a large range of electronic components (along with a host of other heavy elements). Whilst this is not good for the environment the individual is not at immediate risk.
Bigman80
25-11-2018, 18:44
It really isn’t. However, some like to spread FUD, presumably in an attempt to deflect criticism from their own woeful lack of attention to health and safety - like no output protection in their amps (specifically, the ones you use).
A very cursory Google shows that cadmium is present in a large range of electronic components (along with a host of other heavy elements). Whilst this is not good for the environment the individual is not at immediate risk.Let's not go down that road again!!
Antonio, I have looked into the whole cadmium thing after yesterday's comments but in all truth, as YNWan says, it's not really an issue to the consumer. Bad for the environment, yes.
A bit like my deodorant [emoji23]
Question:
Just for talking sake, if you walked into your local Curries and bought, say, a TV, and part of the circuit contained cadmium [let's assume this was possible]. which was claimed as being illegal, would you be expected to know that *before* you bought the TV in question, and thus reject it on that basis, especially when the manufacturer who built it (and the retailer who was selling it), were seemingly both happy that making it available for sale was both safe and legal?:hmm:
If the answer is 'no', then how would that be any different from buying an LDR preamp from a hi-fi manufacturer, on *exactly* the same premise...?
Marco.
P.S In any case, once Brexit kicks in, all this 'banned by the EU' bollocks will be consigned to history!:D
Tv tubes have cadmium in em as does tobacco and tomatos True it's about levels but humans are going to get more exposure to it from someone smoking beside them than from a diode even if it goes pfut
Question:
Just for talking sake, if you walked into your local Curries and bought, say, a TV, and part of the circuit contained cadmium [let's assume this was possible]. which was claimed as being illegal, would you be expected to know that *before* you bought the TV in question, and thus reject it on that basis, especially when the manufacturer who built it (and the retailer who was selling it), were seemingly both happy that making it available to the general public was both safe and legal?:hmm:
If the answer is 'no', then how would that be any different buying an LDR preamp from a hi-fi manufacturer, on *exactly* the same premise...?
Marco.
P.S In any case, once Brexit kicks in, all this 'banned by the EU' bollocks will be consigned to history!:D
The product wouldn’t be for sale as it has to be ROHS compliant from: http://www.rohsguide.com/rohs-faq.htm
Any business that sells applicable electronic products, sub-assemblies or components directly to EU countries, or sells to resellers, distributors or integrators that in turn sell products to EU countries, is impacted if they utilize any of the restricted materials.
Also:
All applicable products in the EU market after July 1, 2006 must pass RoHS compliance.
The only way a product could come to market is if there is explicit exception in place for it.
The product wouldn’t be for sale as it has to be ROHS compliant from: http://www.rohsguide.com/rohs-faq.htm
Yes, but the above presumes that the *product itself* is illegal, due to its use of cadmium, rather than simply cadmium, as a material. Surely it would all depend on how its use has been implemented, and whether that amount exceeds the levels allowed (as mentioned earlier)?
The main point I'm making however, is that any issues pertaining to illegality (or otherwise) is the responsibility of the manufacturer and/or retailer, not the buyer/end-user, as they're simply relying on both to ensure that the product being sold to them complies with the regulations.
Marco.
I'm confused. Is it the LDR or the Khozmo that contains cadmium?
Bigman80
25-11-2018, 19:31
P.S In any case, once Brexit kicks in, all this 'banned by the EU' bollocks will be consigned to history!:D
[emoji23][emoji23] Oh no, don't talk politics.
Bigman80
25-11-2018, 19:33
I'm confused. Is it the LDR or the Khozmo that contains cadmium?I think we were talking Khozmo but appear to be confusing the subject of the discussion. Or maybe it's just me that is confused.
[emoji23][emoji23] Oh no, don't talk politics.
I know... My regular wine-buying trips to France will soon be rather more expensive!;)
And that's about the extent of my interest in Brexit.
Marco.
Ah right. That was my initial impression but then there was a reference to swallowing LDRs.
I know... My regular wine-buying trips to France will soon be rather more expensive!;)
And that's about the extent of my interest in Brexit.
Marco.
Why? So far as I can make out the UK has said they will not be imposing additional tariffs on imports.
I'll believe it when I see it....
Post-Brexit, I'm expecting all sorts of things here in the UK to become rather more expensive than they are now - at least for a period of time initially.
Marco.
Yes, but the above presumes that the *product itself* is illegal, due to its use of cadmium, rather than simply cadmium, as a material. Surely it would all depend on how its use has been implemented, and whether that amount exceeds the levels allowed (as mentioned earlier)?
The main point I'm making however, is that any issues pertaining to illegality (or otherwise) is the responsibility of the manufacturer and/or retailer, not the buyer/end-user, as they're simply relying on both to ensure that the product being sold to them complies with the regulations.
Marco.
Levels yes but use/implementation no. If the levels of the prohibited substance exceeds that laid out in the directive the product will not meet compliance.
Yes the responsibility is with the manufacturer, this is why the directive was put in place, to protect the consumer and the environment. Just like the British kite mark, the CE mark is there to provide a level of protection for the consumer.
Hopefully you have built up a large temperature controlled cellar by now Marco? :cool:
Levels yes but use/implementation no. If the levels of the prohibited substance exceeds that laid out in the directive the product will not meet compliance.
So in the case of the design of an average LDR preamp, how would you determine if the levels used exceeded those laid out in the directive? And if you can't accurately determine/measure them, then it's not guaranteed that the product in question is illegal.
Baring in mind that such products are produced solely by 'artisan' manufacturers, not huge multi-national companies with the necessary resources to test for such. Or is it easy for any manufacturer, large or small, to accurately test for cadmium levels in the design of their products?
Yes the responsibility is with the manufacturer, this is why the directive was put in place, to protect the consumer and the environment.
Indeed, therefore anyone buying an LDR preamp from such a manufacturer (including folks here), is exempt from the responsibility of buying a product claimed as being illegal.
Marco.
Hopefully you have built up a large temperature controlled cellar by now Marco? :cool:
Hang on, and I'll consult my sommelier... I just drink the stuff;)
Marco.
montesquieu
25-11-2018, 20:01
Levels yes but use/implementation no. If the levels of the prohibited substance exceeds that laid out in the directive the product will not meet compliance.
Yes the responsibility is with the manufacturer, this is why the directive was put in place, to protect the consumer and the environment. Just like the British kite mark, the CE mark is there to provide a level of protection for the consumer.
It's not principally about consumers. The directive is primarily to protect:
1) the employees engaged in manufacture - while levels of cadmium may be 'safe' for consumers, this is almost certainly not the case for those exposed in the workplace. The EU could say 'not my problem' but has chosen instead to ban devices containing components with high levels of these substances, in part I'm sure to level the playing field for EU manufacturers but also for sure to make a difference in those places where workers are endangered. Many things have been banned for this reason. And it must surely have an impact in some aspects.
2) the wider environment. To an extent this is the same discussion as the one about palm oil - cheap palm oil is damaging the rain forest. Should we care or should we just enjoy the products made with it and consider environmental impact of our consumption to be a local issue, not worthy of our attention?
BTW we have health and safety rules now for a reason - the reason being that too many nasty things happened when companies were allowed not to care about it, and workers fought over decades to change that. Here's an extreme example https://www.telegraph.co.uk/books/what-to-read/the-forgotten-factory-girls-killed-by-radioactive-poisoning/
I grew up in a steel working town where there were horrific industrial accidents every other week. While some idiotic things have happened - goggles to play conkers springs to mind - overwhelmingly the world is a better place for health and safety legislation.
Bigman80
25-11-2018, 20:02
Levels yes but use/implementation no. If the levels of the prohibited substance exceeds that laid out in the directive the product will not meet compliance.
Yes the responsibility is with the manufacturer, this is why the directive was put in place, to protect the consumer and the environment. Just like the British kite mark, the CE mark is there to provide a level of protection for the consumer.Yet we buy Chinese DACs and don't think twice about plugging them in without the safety marks.
Yet we buy Chinese DACs and don't think twice about plugging them in without the safety marks.
Yeah 'China Export'. The fact that it very closely resembles the Conformité Européenne marking is sheer coincidence. Just one of those crazy accidents of chance.
Yet we buy Chinese DACs and don't think twice about plugging them in without the safety marks.
And Chinese valve amps, too... But then, I don't believe that they feature the use of cadmium. However, in my experience, they're certainly not guaranteed to be electrically safe on our mains voltage!
Marco.
Bigman80
25-11-2018, 20:20
Yeah 'China Export'. The fact that it very closely resembles the Conformité Européenne marking is sheer coincidence. Just one of those crazy accidents of chance.Exactly.
The "UK-Legal" questioning of the Khozmo does feel a little like FUD to be honest.
I'll ask Arek for a comment when I get a chance.
TBH if they told me they made the Khozmo with tears from baby seals, I'd still buy one. Probably two. It IS that good.
So in the case of the design of an average LDR preamp, how would you determine if the levels used exceeded those laid out in the directive? And if you can't accurately determine/measure them, then it's not guaranteed that the product in question is illegal.
Baring in mind that such products are produced solely by 'artisan' manufacturers, not huge multi-national companies with the necessary resources to test for such. Or is it easy for any manufacturer, large or small, to accurately test for cadmium levels in the design of their products
Marco.
No, not true. The steps required to obtain compliance are laid out in the directive, the manufacture will need to check his supply chain and obtain the declaration of conformity for all the parts/components he uses, this includes none electrical parts as well. IE. If buying resistors from RS or Digikey etc, these documents are available on-line from them.
If they have an LED that probably has cadmium in it. But it's okay in LEDs because...whatever. It's boring and no-one cares.
When is this thing turning up then?
Bigman80
25-11-2018, 20:22
And Chinese valve amps, too... But then, I don't believethat they feature the use of cadmium. However, in my experience, they're certainly not guaranteed to be electrically safe!
Marco.That was my point mate. They rarely conform to any UK safety standards yet we're concerning ourselves with cadmium in a stepped attenuator. Ridiculous.
Yet we buy Chinese DACs and don't think twice about plugging them in without the safety marks.
Yeah like the one I bought a few years back with fake CE mark, metal case, IEC inlet and no earth connection...great purchase....not.
Bigman80
25-11-2018, 20:28
Yeah like the one I bought a few years back with fake CE mark, metal case, IEC inlet and no earth connection...great purchase....not.Exactly mate. There's a lot of this sort of thing and for someone to take a stab at a truly wonderful stepped attenuator is ridiculous. We could have an entire thread on unsafe items. The Khozmo wouldn't be in it.
That was my point mate. They rarely conform to any UK safety standards yet we're concerning ourselves with cadmium in a stepped attenuator. Ridiculous.
We might be discussing it, but that doesn't mean we're concerned, especially if we're convinced that there's nothing to be concerned about;)
Oh, and as for the 'disposal of a volatile material' argument, that's only valid if the product in question is disposed of irresponsibly! As an example, the LDR I've received from Chris is likely be with me, sitting safely on my equipment rack, unmolested (as it were), until I croak.
I have no plans whatsoever for getting rid of it in my lifetime, and after that there's no reason why it shouldn't be disposed of responsibly.
So why does it need to be harmful? As ever, it's a question of context!
Marco.
Good idea to clarify things though, don't you think?
Many Chinese valve amps blow up (or at least used to) unless they've been properly sorted for European consumption I remember. Who buys them - a few hobbyist nutters like us probably ;)
My thing with this LDR preamp is all the electronics around said LDR's making 'it' happen with the signal somehow finding its way through the circuit board when a simple 'pot/attenuator in a box' is just the attenuating unit plus a few wires to the sockets.
It's only music ffs... What's the HiFi got to do with it? :D
Exactly mate. There's a lot of this sort of thing and for someone to take a stab at a truly wonderful stepped attenuator is ridiculous. We could have an entire thread on unsafe items. The Khozmo wouldn't be in it.
It's not the Khozmo being discussed, it's light dependant resistors.
Bigman80
25-11-2018, 20:34
It's not the Khozmo being discussed, it's light dependant resistors.[emoji23][emoji23] told you I was confused.
I'll get my coat.........*leaves*
No, not true. The steps required to obtain compliance are laid out in the directive, the manufacture will need to check his supply chain and obtain the declaration of conformity for all the parts/components he uses, this includes none electrical parts as well. IE. If buying resistors from RS or Digikey etc, these documents are available on-line from them.
Ok, so what we need to know is if the parts/components used, in any LDR preamp currently being sold, comply with the above or not. That may or may not be the case - we don't know for sure without the necessary evidence.
The main point is, it's not the case that ALL LDRs, by default, are illegal. It's all down to the levels of cadmium present. The former claim is simply ridiculous scaremongering, generated by manufacturers with commercial agendas, and potentially something to lose from competitors selling LDRs.
Marco.
Wakefield Turntables
25-11-2018, 20:53
Cadmium, who gives a $#!t, the components are going to be encased and are only really problem if you actually touch them. I don't see many Garrard 301 / 401 owners who have multiple components cadmium coated whinging about H&S, FFS get a grip. It's a pre-amp, I'm actually really looking forward to the review of the pre-amp, it's been ages since Marco has review anything, should be fun. Remember that?
Cadmium, who gives a $#!t, the components are going to be encased and are only really problem if you actually touch them. I don't see many Garrard 301 / 401 owners who have multiple components cadmium coated whinging about H&S, FFS get a grip. It's a pre-amp, I'm actually really looking forward to the review of the pre-amp, it's been ages since Marco has review anything, should be fun. Remember that?
Spot on, Andy, especially the above, and your point about having FUN (what LIFE ITSELF is all about, not just hi-fi)!! :exactly:
Unfortunately, there are some very bitter and irascible malcontents out there, determined to suck all the FUN out of this hobby of ours, simply because of their pathetic grudges and HUGE chips on their shoulders:rolleyes:
And I will *never* allow AoS to be negatively influenced by their blinkered and deliberately misleading bullshit. As such, I look forward to using/owning and reviewing the LDR in question, whilst offering a two-fingered salute to the fun-hoovering, wank-stained, agenda monkeys out there!:upyours::upyours:
Marco.
Wakefield Turntables
25-11-2018, 21:08
I have a small confession to make :o I did strip away all the cadium from the linkages when I restored my 301. I'm still alive apart from the second head I developed and far from :deceased:.
I have a small confession to make :o I did strip away all the cadium from the linkages when I restored my 301.
Lol... Word has it, it's an aphrodisiac:eek::D
Marco.
Wakefield Turntables
25-11-2018, 21:14
It's neurotoxic old bean so it will make things wilt! You'll not be seeing any of this :flasher:.
It's neurotoxic old bean so it will make things wilt! You'll not be seeing any of this :flasher:.
Heh-heh.... Can't have that then, eh? Some of us still get more than just a five-finger shuffle every Christmas:eyebrows:
Marco.
Wakefield Turntables
25-11-2018, 21:32
Some of us still get more than just a five-finger shuffle every Christmas:eyebrows:
Marco.
We might have a review from you if you spent less time doing this particular activity :wanker:.I can't believe I've used so many different smileys.
More seriously, in terms of this subject, as I mentioned before, when the UK leaves the EU on 29th March 2019, we'll no longer be subject to EU law, and that may include the ban on cadmium.
That provides plenty of time to raise awareness here of any sonic/musical advantages I perceive with the use of a well-designed LDR, and I don't give a monkeys if that should adversely affect the sales of anyone selling conventional passive preamps, which is the *ONLY* reason one manufacturer in particular has a mania about cadmium;)
Marco.
Well my post seemed to increase the flow on this thread, with some interesting info, I only saw one comment that had no relevance to this thread.
I was interested to read the review thread, and although Macca heard the LDR's he did not change his regular pre. He has however heard the DCB1 and this has encouraged him to purchase one for a long term comparison.
Bigman80
26-11-2018, 07:17
I only saw one comment that had no relevance to this thread.
Was it mine [emoji23][emoji23]
Spot on, Andy, especially the above, and your point about having FUN (what LIFE ITSELF is all about, not just hi-fi)!! :exactly:
Unfortunately, there are some very bitter and irascible malcontents out there, determined to suck all the FUN out of this hobby of ours, simply because of their pathetic grudges and HUGE chips on their shoulders:rolleyes:
And I will *never* allow AoS to be negatively influenced by their blinkered and deliberately misleading bullshit. As such, I look forward to using/owning and reviewing the LDR in question, whilst offering a two-fingered salute to the fun-hoovering, wank-stained, agenda monkeys out there!:upyours::upyours:
Marco.
ROHS defines electrical and electronic equipment (EEE) as equipment that encompasses finished product ‘for direct use by the end user’ and also product as a 'component' placed on the market for further production or integration into a finished product, as the LDR pre-amp boards come populated and ‘complete’ and are intended to ‘perform an electrical function’ in a finished product they fall within the scope of ROHS. As no distinction is made between DIY or commercial product the above is an umbrella definition.
Important links:
Cadmium and you: Working with cadmium: Are you at risk? http://www.hse.gov.uk/pubns/indg391.pdf
ROHS REGULATIONS: Government Guidance Notes https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/31803/11-526-rohs-regulations-government-guidance-notes.pdf
Significant points:
EU amendment 2012/51/EU provided an exemption to the ROHS2 directive 2011/65/EU allowing the use of LDRs containing cadmium in Professional Audio Equipment. It is worth noting ROHS makes no distinction between professional and domestic uses EXCEPT when an amendment applies as in 2012/51/EU, therefore the amendment did not apply to domestic audio equipment, ever. Professional is defined as 'use by a professional' IE: by somebody working in a Professional capacity.
This amendment EXPIRED at the end of December 2013 and no extension or renewal application for it has been made or granted since...therefore the exemption for the use of "Cadmium in photoresistors for analogue optocouplers applied in professional audio equipment" under the ROHS2 directive no longer applies and never applied for domestic use, ever.
This means the importing and sale of these complete boards is illegal in the EU as it stands today. It does not matter that now alternative to an LDR is available, the legality of their use EXPIRED at the end of Dec 2013 and that legal exemption only covered Professional use.
The directive does allow though for the supply and sale of 'spare parts' where those parts are sold for the repair, reuse, updating or upgrading of specific EEE. Hence RS and Farnell can sell the LDR as a component.
With regard to some of the comments made elsewhere about other uses of cadmium and other harmful substances, yes, there is widespread use but a lot of this use is covered by specific exceptions to the directive like the use in PV panels... it's worth noting that NiCad batteries are already under 'use restriction' and that at the end of 2016 their use becomes illegal.
www.europarl.europa.eu/news/en/news-room/content/20131004IPR21519/html/MEPs-ban-cadmium-from-power-tool-batteries-and-mercury-from-button-cells
You had better hope that Brexit happens.:rolleyes:
Note that the limit for cadmium is 0.1% by weight, so the LDR is probably just about legal, but it depends on your opinion of the regulations.
More seriously, in terms of this subject, as I mentioned before, when the UK leaves the EU on 29th March 2019, we'll no longer be subject to EU law, and that includes the ban on cadmium.
That provides plenty of time to raise awareness here of any sonic/musical advantages I perceive with the use of a well-designed LDR, and I don't give a monkeys if that should adversely affect the sales of anyone selling conventional passive preamps, which is the *ONLY* reason one manufacturer in particular has a mania about cadmium;)
Marco.
I seriously doubt it. EU law will be rolled into British law and we’ll still have to abide by it, plus to continue to trade with the EU will mean we still have to stick with their laws.
The main point is, it's not the case that ALL LDRs, by default, are illegal. It's all down to the levels of cadmium present. The former claim is simply ridiculous scaremongering, generated by manufacturers with commercial agendas, and potentially something to lose from competitors selling LDRs.
Marco.
Well I’ve yet to find one that meets RoHS, the one referenced to earlier by Chris for audio use doesn’t meet RoHS as it appears to contain lead.
Well my post seemed to increase the flow on this thread, with some interesting info, I only saw one comment that had no relevance to this thread.
I was interested to read the review thread, and although Macca heard the LDR's he did not change his regular pre. He has however heard the DCB1 and this has encouraged him to purchase one for a long term comparison.
I also have an LDR pre-amp - it just needs some work on the volume control that I've not got around to yet.
As regards the legality/illegality I couldn't care less. I'll buy whatever I damn-well please.
Well I’ve yet to find one that meets RoHS, the one referenced to earlier by Chris for audio use doesn’t meet RoHS as it appears to contain lead.
"Appears", is not proof of anything. The only way you'd know for sure is to examine the unit in question appropriately, so until then you (or anyone else) is not qualified to state whether it meets RoHS regulations or not.
As an aside, Kevin makes some good points here: https://theartofsound.net/forum/showthread.php?60703-LDR-preamp-build&p=1034832#post1034832
Marco.
As regards the legality/illegality I couldn't care less. I'll buy whatever I damn-well please.
Hear, hear!! :clap:
Word, bro.
Marco.
I seriously doubt it. EU law will be rolled into British law and we’ll still have to abide by it, plus to continue to trade with the EU will mean we still have to stick with their laws.
Well, we'll see. If that's the case, then the status quo is retained, and I'll simply default to Macca's position on the matter!;)
Marco.
Anyway guys, there's been enough chat on this cadmium bollocks, so I now insist that all further posts made are in relation to LDRs in general, or their sound quality. Anything else will be removed without further notice.
As Andy mentioned, it's time to put the FUN back into this thread and return to discussing hi-fi!:cool:
Marco.
I also have an LDR pre-amp - it just needs some work on the volume control that I've not got around to yet.
As regards the legality/illegality I couldn't care less. I'll buy whatever I damn-well please.
I did not know you had a LDR Pre, my thoughts were you had heard one and decided to stay as you were.
If your last comment was aimed at me, I have never said you cannot buy one.
I did not know you had a LDR Pre, my thoughts were you had heard one and decided to stay as you were.
If your last comment was aimed at me, I have never said you cannot buy one.
I got it a fair few years ago now - if something interests me I'll generally buy one so I can evaluate it at leisure - and no, my last comment not aimed at you. :)
One last point on these.
The LDRs within are illegal, and do not meet ROHS requirements. You already know that.
The important point:
If it breaks, please dispose of it properly, and don’t just dump it in the bin where it will more than likely find it’s way to a landfill site.
Kevin,
I did say no more comments on this, and when I say no more discussion on a particular subject I *mean* it. Therefore, I will respond, and then that't an END to the matter.
One last point on these.
The LDRs within are illegal, and do not meet ROHS requirements. You already know that.
No I don't, not for sure (beyond question) until one has been properly examined. I repeat what I said earlier to Neal:
"Appears", is not proof of anything. The only way you'd know for sure is to examine the unit in question appropriately, so until then you (or anyone else) is not qualified to state whether it meets RoHS regulations or not.
The important point:
If it breaks, please dispose of it properly, and don’t just dump it in the bin where it will more than likely find it’s way to a landfill site.
Indeed - now *that* is an important point, simply because if the cadmium content is not tampered with and doesn't find its way into landfill, then it creates no danger to anyone whatsoever. Therefore, the key, if you're going to dispose of anything containing cadmium, is to dispose of it RESPONSIBLY.
Now, if I see any more comments here on this subject, the posts in question will be removed and the user banned for a week. Let's get back to discussing HI-FI!:cool:
Marco.
Marco If you will allow me one last courtesy to reply on this debate I asked for clarification from the manufacturer, their reply:
Hello Mr ,
Thank you for the inquiry below.
Our part number NSL-32SR3 contains cadmium which makes the part non-RoHS compliant (with no exceptions reported).
At this time, we do not have a compliant alternative to offer.
Kind regards,
Kim Garcia
Inside Sales Manager
(805)987-0146
KGarcia@AdvancedPhotonix.com
Ok, that's fine, but it's not *conclusive* proof that the LDRs discussed here are 'illegal', as there are still too many grey areas.
Now *that* is an end to the matter. The next person to post on this thread on the subject of cadmium will be out for a week, regardless of any pleas!
Let's get back to HI-FI now, and for the remainder of this thread, STAY on HI-FI matters:cool:
Marco.
ha, ha, ... oh sorry. Still talking about that cad..
I have one of Chris LDR attenuators, I guess one of the first ones. I sometimes take it out of the chain and swap it out with a Dada'd Quad 34 . But after a while it always finds its way back into my stereo. Wonder why ?
Hi All
How good is this LDR pre
I've been following in the hope of a review
S.
Well I have the LDR with 2010 boards. Massively open, detailed and punchy. Single input, battery powered.
Chris has sent me his updated 2018 boards but I have yet to install them. Stuff like work gets in the way. :)
Wanna try the 2010 version for a while and do a review? Good to know compared to the DCB1 you built.
Do you come up to London sometime? PM if you wish.
E
Well I have the LDR with 2010 boards. Massively open, detailed and punchy. Single input, battery powered.
Chris has sent me his updated 2018 boards but I have yet to install them. Stuff like work gets in the way. :)
Wanna try the 2010 version for a while and do a review? Good to know compared to the DCB1 you built.
Do you come up to London sometime? PM if you wish.
E
Hi Edward
I only ever get to north London, Stanford hospital.
Quite like the idea of putting the ldr against the dcb1 for a comparison in sound.
S.
Light Dependant Resistor
23-02-2019, 00:28
Looks like a really tidy build. Looking forward to reading the feedback.
Can it oust Marcos Croft pre?
Eagerly awaiting for that comparison
Bigman80
23-02-2019, 00:28
Eagerly awaiting for that comparisonI'll bet!
Eagerly awaiting for that comparison
Indeed, so am I... It's getting nearer though, thank goodness!:doh:
Don't worry, you'll be the first to know the results, Chris, as soon as I've carried out a proper comparison.
Marco.
I gave some of my thoughts on the latest LDR (all positive) in a thread started by Firebottle.
E
Typing from a warm sunny Sri Lanka. :)
§
I gave some of my thoughts on the latest LDR (all positive) in a thread started by Firebottle.
E
Typing from a warm sunny Sri Lanka. :)
§
nice holiday Ed..:)
Any updates Marco?
I’d be interested in trying one of these but would appreciate your opinions compared to the valve preamp.
Thanks :cool:
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