Depends what you mean by technical ... any non-linear resistance where the design has assumed there to a correct continuity is liable to cause effects. As a mental exercise, consider the whole circuit, every component on the board, is connected on the board not by solder, but by a plug-in arrangement - what faith would you have that the performance in every area would match that of a fully soldered board?
Personal experience. Every time I reduced the number of non-soldered connections in a system the sound improved; I don't need a textbook to confirm the value of doing this. And, I very specifically don't like gold to gold, I spent quite a lengthy period confirming that unless the connection is truly gas-tight that electrically such a connection is not good enough, at least in the audio game ...
All the preamps would probably improve in quality if the connections were soldered ... and there would still be differences due to variations in topology and component quality.Are you saying that you're 100% sure that the character of sound of this design and of opamps themselves is purely a result of poor connections? Would the major hassle of unsoldering all those sockets and soldering in the opamps 100% make the SQ of this design equal to that of the others? Surely you can see there's a logical flaw in that argument - swapping opamps produces a different sound but they are in the same sockets! Furthermore, the other opamp preamps I'm comparing it to contain the same dreaded socketed ICs and yet they are ok
The opamps would vary in their susceptibility to less than perfect connections, hence variation in sound quality.
Personally, if I had the units, I would carefully solder the opamps to the sockets as is - removing the socket entirely would be of only marginal benefit.
Hi Alex, Frank,
In this case it is a much better PCB than SC has ever produced, having been designed (I gather) by a professional PCB designer, though certain SC staff seem to be getting better. While the pads may be slightly smaller, being plated through the holes can withstand a lot more rework as they tend to stop the pads from peeling away. The problem is to de-solder an IC you need to cut the legs, thereby wrecking it in the process. Plus of course it's very time consuming with quite a few opamps involved.
Frank I would have no issue if you'd said your experience was that soldering ICs into designs where they were previously socketed had improved SQ on many occasions and you were sure of this because you had two of the same design, one with sockets and one without, to compare directly, especially if you admitted there was no clear reason why. But start by implying I'm a fool to have used sockets because you know better based on audiophile pseudo scientific speculation like "low level distortion" due to lack of integrity etc and I lose all interest. And your remarks on needing to let things settle reminds me of my audiophile friends who keep their system on 24/7 because they're convinced it takes 3 days to start sounding good after being switched on from cold. And that the type of wood their CD player sits on affects the sound massively. Etc etc. Sorry but I'm not interested in the whole mystical side, only the art and science
Plenty of faith if they were high quality connectors. I spend my days working on state-of-the-art medical imaging equipment that contains literally hundreds of connectors (with wires crimped into them too) with thousands and thousands of connections, and I'm quite sure their performance and reliability would not be improved by soldering every single connection. Not to mention how much fun servicing them would be then. And before you say anything I've rarely if ever seen any of this equipment fail due to the connectors. Now I know audio is a different beast as it involves our emotional response, but I don't see that's a good excuse to disregard physics and start inventing mysterious reasons for things.
More Golden Rule (no pun intended
) dogma based on extrapolating one observation into a general principle - eg replacing an electrolytic capacitor in a particular part of one design improved the sound, therefore all electrolytic capacitors must degrade the sound in any part of any circuit (presumably as they also add low level distortion ). Having studied materials engineering at uni, I'm pretty sure I recall correctly that dissimilar metal joints are bad news in terms of corrosion. Hard to see why gold to gold would be so bad and a solder joint so much better. And as for gas tight, well electrons are pretty small. The part of the IC leg that's in contact with the socket hole, however small this area, is just as gas tight as a solder joint. That's how crimping works, right?Oh so now you're saying the SQ difference is due to component and circuit differences after all, just that I can't observe this legitimately until I've soldered every single connection?
But wait, if this only applies to opamps themselves that must mean another win for the legendary 5532 - it is so much more resistant to the effects of imperfect socket connections (solder joints always being perfect of course) than the LM4562.
We are really seeing things from two different angles here - I perceive worrying about the precise nature of the opamp as heading across to the audiophool camp, I've heard excellent sound coming through the most mangy of these little critters - provided I sorted out the other things that I've been mentioning ...
If you're happy that your IC sockets are gas-tight quality then probably best to leave this conversation at this point ...
If you're happy that your IC sockets are gas-tight quality then probably best to leave this conversation at this point ...
Well I can certainly respect and agree to that. I'm not saying I completely disbelieve this could ever make a difference to SQ, just that your pseudo-technical arguments as to why are unconvincing. You did make the original statement pretty bluntly after all. I would prefer to solder all the opamps in if I was sure I would never change them, and may still do so. But I'm very skeptical of hearing any difference as a result.
And you may note that I have never said or thought that the design isn't sounding good because of the opamps it uses so I'm not "worrying about the precise nature of the opamp". I think 5532s can sound pretty good and rather that it's some aspect of this design that is having the effect on SQ. Anway
And you may note that I have never said or thought that the design isn't sounding good because of the opamps it uses so I'm not "worrying about the precise nature of the opamp". I think 5532s can sound pretty good and rather that it's some aspect of this design that is having the effect on SQ. Anway
My apologies if my original statement came across as being too blunt!! Would be my Germanic heritage getting the better of me, then ...You did make the original statement pretty bluntly after all. I would prefer to solder all the opamps in if I was sure I would never change them, and may still do so. But I'm very skeptical of hearing any difference as a result.
And you may note that I have never said or thought that the design isn't sounding good because of the opamps it uses so I'm not "worrying about the precise nature of the opamp". I think 5532s can sound pretty good and rather that it's some aspect of this design that is having the effect on SQ. Anway
Cheers, too,
Self's Variable Tone Control Preamplifier
I cannot find anyone on the forum actually answering your question (above). I have just ordered a copy of the Linear Audio Self article, so I am in the evaluation stage, but having built Self's original Advanced Preamplifier (still going strong) I am expecting his new design to be excellent.
Hence my question: Is anyone(or group) planning to build the variable tone control preamp and are there sources for PCBs for the project?
Are there any Forums addressing any of this?
Thanks for the help
George
Hi Carl,
I cannot find anyone on the forum actually answering your question (above). I have just ordered a copy of the Linear Audio Self article, so I am in the evaluation stage, but having built Self's original Advanced Preamplifier (still going strong) I am expecting his new design to be excellent.
Hence my question: Is anyone(or group) planning to build the variable tone control preamp and are there sources for PCBs for the project?
Are there any Forums addressing any of this?
Thanks for the help
George
Variable Tone Preamp
Based on my experience with Doug Self's designs, I shall be in the queue with you.
His Advanced Preamplifier design had switchable turnover points for the tone controls and I found them useful. Actually that Pre-amp is just 3 feet away.. I use it for ripping LPs onto myNAS. It has always worked perfectly.
Thanks fro that information
George
Based on my experience with Doug Self's designs, I shall be in the queue with you.
His Advanced Preamplifier design had switchable turnover points for the tone controls and I found them useful. Actually that Pre-amp is just 3 feet away.. I use it for ripping LPs onto myNAS. It has always worked perfectly.
Thanks fro that information
George
Hi George, Carl, others.
I few years back I did a layout of the original, using SMT & THT, but never mfg the pre-amp, due to cost overruns. Since I have the design captured for layout and Pspice, it would not be too much work to re-visit the design again. I guess that i have to pony up to Jan D. & get the article however.
Recall it was a real rats nest to sort out. Lucky, I was doing the pcb in 4 layers so power/gnd was so much easier. Do not suspect people would wan ta 4-layer pcb however for a simple design like this one.
I have issue of usefulness of a stand alone pcb that only has one function and is not a complete system = market
I was contemplating doing it electronically, but gets involved. Probably using a CS3318, as TI PGA2311/4311 method requires more pkgs.
I realize however that tone controls do not necessarily need to be electronically controlled.
I also have a 4 channel parametric eq. design from 1978 that does a better job, if tone control is your thing. It used TL074 so it is screaming for an upgrade as well.
Rick
Not that I am aware of.
I few years back I did a layout of the original, using SMT & THT, but never mfg the pre-amp, due to cost overruns. Since I have the design captured for layout and Pspice, it would not be too much work to re-visit the design again. I guess that i have to pony up to Jan D. & get the article however.
Recall it was a real rats nest to sort out. Lucky, I was doing the pcb in 4 layers so power/gnd was so much easier. Do not suspect people would wan ta 4-layer pcb however for a simple design like this one.
I have issue of usefulness of a stand alone pcb that only has one function and is not a complete system = market
I was contemplating doing it electronically, but gets involved. Probably using a CS3318, as TI PGA2311/4311 method requires more pkgs.
I realize however that tone controls do not necessarily need to be electronically controlled.
I also have a 4 channel parametric eq. design from 1978 that does a better job, if tone control is your thing. It used TL074 so it is screaming for an upgrade as well.
Rick
Last edited:
From what I have been following isn't this pre-amplifier offered in kit form? I forgot the name of the outfit that Doug is associated with but I know there are others who have built this pre and discussed it in another thread. Am I missing something here? Perhaps it is Elektor that I am thinking of, though I may be spelling that incorrectly?
First there was the 1996 precision preamp:
The Signal Transfer Company: Precision Preamplifier.
The subject of this thread (2012 precision preamp) is a kit of boards available (for better or worse) from Elektor Magazine who, I think, hold the copyright.
The Signal Transfer Company: Precision Preamplifier.
The subject of this thread (2012 precision preamp) is a kit of boards available (for better or worse) from Elektor Magazine who, I think, hold the copyright.
On the other hand
I think I read somewhere that the Precision preamp kit was going to be upgraded with variable tone controls too. However that is just one large motherboard and most of it I don't need. A stand-alone tone control module to insert after my preamp would be ideal. I suppose I could even rescue the switchable tone control from my 1976 Self Advanced Preamplifier but surely things have improved since then?
George
I think I read somewhere that the Precision preamp kit was going to be upgraded with variable tone controls too. However that is just one large motherboard and most of it I don't need. A stand-alone tone control module to insert after my preamp would be ideal. I suppose I could even rescue the switchable tone control from my 1976 Self Advanced Preamplifier but surely things have improved since then?
George
Yes, you are correct. The latest from DS is the 2012 Pre featured in Elektor last year. 3 or 4 part series. I don't believe the Linear Audio article address the Elektor pre or not, although the tone control circuits may be the same or very similar. Don't have the articles in front of me to verify. I built the 2012 pre and couldn't be happier with it's performance. Albeit a significant project and investment ($).
Rick
The Signal Transfer Company: Precision Preamplifier
Quite possible? not sure if this design uses the new tone ckt or the older one?
Says, only opamps used are NE5532 & TL072! so does the new tone control ckt use other types of opamps?
We have now 4 designs here in discussion
1) Original Precision pre-amp '96 as published in "Self on Audio" & was, I recall, offered by Signal Transfer co. earlier.
2) Elektor 2102 pre-amp
3) new tone control ckt as published in LA vol6
4) The Signal Transfer Company: Precision Preamplifier
Tone control in Elektor 2102 pre-amp is not the variable freq tone control.
Rick
Quite possible? not sure if this design uses the new tone ckt or the older one?
Says, only opamps used are NE5532 & TL072! so does the new tone control ckt use other types of opamps?
We have now 4 designs here in discussion
1) Original Precision pre-amp '96 as published in "Self on Audio" & was, I recall, offered by Signal Transfer co. earlier.
2) Elektor 2102 pre-amp
3) new tone control ckt as published in LA vol6
4) The Signal Transfer Company: Precision Preamplifier
Tone control in Elektor 2102 pre-amp is not the variable freq tone control.
Rick
Last edited:
The preamp that holds Dougs latest tone control vision can be found only here ...
A low-noise preamplifier with variable-frequency tone controls
Linear Audio volume 5
A low-noise preamplifier with variable-frequency tone controls
Linear Audio volume 5
Preamp of Interest
Yes, I think that about sums it up.
Personally I would like to build the version from LA (vol 5, not vol6). However, in the absence of PCBs I shall probably fall back on the Elektor version. Of course if PCBs become available and the tone control is modular in the sense of the Elektor design then the LA design, having upgraded opamps, is the version of choice.... for me at least.
Yes, I think that about sums it up.
Personally I would like to build the version from LA (vol 5, not vol6). However, in the absence of PCBs I shall probably fall back on the Elektor version. Of course if PCBs become available and the tone control is modular in the sense of the Elektor design then the LA design, having upgraded opamps, is the version of choice.... for me at least.
I guess this calls for a bit of a criticism of many mag articles in that they do not supply people with easy access to pcb's or faqb files, to evaluate. Elektor has figured this out in the most part, so did old popular electronics.
Doug Self gave Bob Cordell a similar slam, that in Bob's PA design book, there was no living proof that the ckts worked in reality. Only simulations supposedly except for the original MOSFET design that was published many moons ago. pooh pa.
I did offer to Bob C. that i'd layout a few selected ckts for him but he did not seem too interested in my offer.
I do not have the LA article so do not know how this new tone control ckt has been tested out.
Oh well it is DIY so you have to layout your own ckts it seems.
Doug Self gave Bob Cordell a similar slam, that in Bob's PA design book, there was no living proof that the ckts worked in reality. Only simulations supposedly except for the original MOSFET design that was published many moons ago. pooh pa.
I did offer to Bob C. that i'd layout a few selected ckts for him but he did not seem too interested in my offer.
I do not have the LA article so do not know how this new tone control ckt has been tested out.
Oh well it is DIY so you have to layout your own ckts it seems.
1976!
Just to get my feet back on the ground, after going round in circles re. the Self pre-amp / tone controls/ kit .... I decided to resurrect the 1976 Advanced Preamplifier that I built many years ago. Apart from some poor volume controls it sounds pretty good .. in fact I hate to say it, but overall I prefer it to the sound of the Pass B1 buffer! No hate mail please.
My construction back in those days left a lot to be desired but is encouraging... and I am assuming that Self + New technology has improved a lot since then. So, the B1 is coming out and in goes a 1976 design until I get the 2012 or later Self design implemented!!!
Just to get my feet back on the ground, after going round in circles re. the Self pre-amp / tone controls/ kit .... I decided to resurrect the 1976 Advanced Preamplifier that I built many years ago. Apart from some poor volume controls it sounds pretty good .. in fact I hate to say it, but overall I prefer it to the sound of the Pass B1 buffer! No hate mail please.
My construction back in those days left a lot to be desired but is encouraging... and I am assuming that Self + New technology has improved a lot since then. So, the B1 is coming out and in goes a 1976 design until I get the 2012 or later Self design implemented!!!