Please, I am not being snarky here.
I have noticed here and elsewhere some very enlightened ideas on modifying. Even jumping in the old WAYBACK machine to remember the original POOGE in AA and SB.
But, I also see a lot of completely naïve attempts that may be more informed by a golden ear magazine reviewer than by sound engineering. Pun intended.
So, before you take on a mod, which I do encourage:
What do you know, or think you know, the original designer did not? Write it down. Look at it.
What do you think is deficient?
New technology?
Cost?
Different use?
Different feature?
Faulty design?
Packaging to suit your taste?
Can you measure the before and after?
Can you simulate the change?
Where did the idea come from? Understanding of circuit design, or some blogger's hot tip?
Many suggestions are well meaning and at first blush sound reasonable until think about it. $500 for some magic high purity gold plated cryogenically treated bi-wire jumpers? From a real engineering standpoint, a steel nail works just as well. Seriously. Save the cryo-treatment for your bench chisels. It works there following the laws of physics. ( Narlex Rictor, yea they do hold their edge better)
Cap can have issues, but some brand name will magically be better? Why? What value in the cap ( many) are you changing and how does that effect the circuit?
We have real data on resister design. Real data on Johnson noise, inductance and measured distortion, yet I almost never see mods concerning that.
I just saw a post where someone noticed a cap that was apparently hot to the touch. OK, sounds bad to me. Why? Mistake? Cheap? Fault? But the answer was a heat sink.
Another comment on adding I assume some magic film on a cap to reduce vibration or something. But that could be insulating causing a perfectly good component selection to run hotter than designed and fail.
I almost NEVER see anything about improving speaker crossovers, a huge opportunity. Even in the multi-thousand dollar speakers range, I see iron core inductors, too mall gauge inductor wire, wire wound resisters and electrolytic caps. That does not even count the overly simplistic design ignoring critical phase and linearity features the left out due to cost.
All I am saying is to think about what you are doing. There is almost nothing out there some thinking and money can't improve. Just think about it first. Consider where your ideas came from. Who knows, you might discover something really cool! You also might destroy an otherwise decent bit of kit.
This does not even approach the really discussing snake oil. $5,467 for a power cord to plug into what? Yea, 200 feet of Romex to you entrance panel. Several hundred if not thousand feet of aluminum wire to the pole. There are actually reviews testing power cords with claims of sonic magic bringing out details in the music. Really. A year long "shootout" of 27 power cords. How does someone with the where-with-all to buy a $5000 power cord get that kind of money? Clearly not with any common sense.
I saw an "audio grade" outlet for over $1000. Do use the $8 comercial grade outlets. Replace all the 97 cent "spec" grade in you house. Your stereo won't sound better, but less likely to fatigue, cause bad contact, and a fire. And don't use the push in terminals. Of course, don't do his unless you are an electrician, and if so, you know that anyway.
Hey, if you want to paint your amp case hot pink, that is your thing if you think it looks better. That's a valid reason. Not that someone said it would "brighten up the sound"
I have noticed here and elsewhere some very enlightened ideas on modifying. Even jumping in the old WAYBACK machine to remember the original POOGE in AA and SB.
But, I also see a lot of completely naïve attempts that may be more informed by a golden ear magazine reviewer than by sound engineering. Pun intended.
So, before you take on a mod, which I do encourage:
What do you know, or think you know, the original designer did not? Write it down. Look at it.
What do you think is deficient?
New technology?
Cost?
Different use?
Different feature?
Faulty design?
Packaging to suit your taste?
Can you measure the before and after?
Can you simulate the change?
Where did the idea come from? Understanding of circuit design, or some blogger's hot tip?
Many suggestions are well meaning and at first blush sound reasonable until think about it. $500 for some magic high purity gold plated cryogenically treated bi-wire jumpers? From a real engineering standpoint, a steel nail works just as well. Seriously. Save the cryo-treatment for your bench chisels. It works there following the laws of physics. ( Narlex Rictor, yea they do hold their edge better)
Cap can have issues, but some brand name will magically be better? Why? What value in the cap ( many) are you changing and how does that effect the circuit?
We have real data on resister design. Real data on Johnson noise, inductance and measured distortion, yet I almost never see mods concerning that.
I just saw a post where someone noticed a cap that was apparently hot to the touch. OK, sounds bad to me. Why? Mistake? Cheap? Fault? But the answer was a heat sink.
Another comment on adding I assume some magic film on a cap to reduce vibration or something. But that could be insulating causing a perfectly good component selection to run hotter than designed and fail.
I almost NEVER see anything about improving speaker crossovers, a huge opportunity. Even in the multi-thousand dollar speakers range, I see iron core inductors, too mall gauge inductor wire, wire wound resisters and electrolytic caps. That does not even count the overly simplistic design ignoring critical phase and linearity features the left out due to cost.
All I am saying is to think about what you are doing. There is almost nothing out there some thinking and money can't improve. Just think about it first. Consider where your ideas came from. Who knows, you might discover something really cool! You also might destroy an otherwise decent bit of kit.
This does not even approach the really discussing snake oil. $5,467 for a power cord to plug into what? Yea, 200 feet of Romex to you entrance panel. Several hundred if not thousand feet of aluminum wire to the pole. There are actually reviews testing power cords with claims of sonic magic bringing out details in the music. Really. A year long "shootout" of 27 power cords. How does someone with the where-with-all to buy a $5000 power cord get that kind of money? Clearly not with any common sense.
I saw an "audio grade" outlet for over $1000. Do use the $8 comercial grade outlets. Replace all the 97 cent "spec" grade in you house. Your stereo won't sound better, but less likely to fatigue, cause bad contact, and a fire. And don't use the push in terminals. Of course, don't do his unless you are an electrician, and if so, you know that anyway.
Hey, if you want to paint your amp case hot pink, that is your thing if you think it looks better. That's a valid reason. Not that someone said it would "brighten up the sound"
About loudspeaker crossover modifications: as a rule don't unless your measurement equipment and environment are better than that of the loudspeaker company. What may look like too thin wire on an inductor, for example, may actually be just right because the incorporated resistance is part of the design.
Thank you! I have been trying to redesign a dynaco mk4 driver board in an attempt to use more common tubes. (And improve overall specs.) I have really learned a lot from the original design and other attempts targeted at the ST 70. It's amazing how hard it is to get a meaningful improvement. Please, have a great deal of respect for the original design when attempting a redesign. Keep this in mind when offering advice to others.
Was hoping by now we wouldn't keep hearing the same old argument that power cords only act as resistors, simply adding with all the other resistance in the power distribution system. A more up-to-date view might be that some power cords can act as distributed filters. One engineer said he investigated why a preamp sounded different with different power cords. He decided that RFI/EMI from the AC power line was making its way into the preamp power supply which then looked like modulation of the preamp noise floor (different power cords measured as being correlated with different FFT noise floor levels that then varied further in level with the presence of an audio signal). A power filter was fitted to the preamp which fixed the problem. So, probably best not to assume people reporting SQ changes with power cords are necessarily imagining things. At least we can agree some power cord prices are way too expensive. That said, having custom cable manufactured can get expensive, especially if several prototypes have to be built before a final design is arrived at.
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vacuphile, good point on the loudspeaker xovers! Replacing an iron core LPF choke in series with the woofer by an ironless air cored one certainly will affect the woofer's QTS parameter, unless the new one is overly bulky and heavy to keep the DCR unchanged.
A xover might be improved, though, if polarized electrolytics (yes, I've encountered that indeed!) are replaced by non polarized ones or plastic foil capacitors. This mod might impact it's durability rather than it's sonic properties.
In any other aspect I fully concur with tvrgeek.
A xover might be improved, though, if polarized electrolytics (yes, I've encountered that indeed!) are replaced by non polarized ones or plastic foil capacitors. This mod might impact it's durability rather than it's sonic properties.
In any other aspect I fully concur with tvrgeek.
I agree in a large part, but often come in conflict with engineers who only look at objective numbers and not to the subjectivity of "good sound" (whatever that may be for you). I like a healthy dose of harmonic distortion, i like a slow roll-off of high frequency in speaker and can put that to numbers. But some say i should not like that because it's not mathematical perfect. But perfect does not exist and different people find different things important, so opinions vary on what sounds good and that should not be a problem.
But it's true all is measurable, it's only that we may not know how to measure some things yet. But if you say it's better i also want to see why on a scientific based arguments and so.
But it's true all is measurable, it's only that we may not know how to measure some things yet. But if you say it's better i also want to see why on a scientific based arguments and so.
I guess NPE’s could be replaced with a mylar and resistor to get the ESR the same - then you never have to worry about them going bad. The problem with replacing vintage NPEs when repairing or revitalizing an old speaker is that you have no way of knowing what the ESR was when it was new. You could guess, and it may or may not be that critical. But you may or may not duplicate the original sound. The tendency is to realize that it instantly sounds brighter with a new poly cap in there instead of a forty year old dried out electrolytic.
When I “upgrade” amplifiers it’s usually limited to increasing undersized coupling (and sometimes power supply) cap values so they don’t eat as much bass, and using transistors with improved SOA so it doesn’t blow again.
When I “upgrade” amplifiers it’s usually limited to increasing undersized coupling (and sometimes power supply) cap values so they don’t eat as much bass, and using transistors with improved SOA so it doesn’t blow again.
Before you do, you have to understand the technical basics. You wouldn't go to the cliff, jump off and flap your arm fast trying to fly just because you've seen a claim that someone can, would you? You wouldn't bring home a dog poop after feeding it special diet that claims to produce fragrant poops that can be used for room air freshener, would you? You wouldn't if you understand the technical basics but the boutique audio shills are counting on the consumers' lack of basic technical understanding on the the subject.
But you didn't bother to find out that all important how the listening comparison was conducted because the report fits your business agenda, right? Just by moving your head couple inches while using the same power cord can sound different, especially in a room like this one.
You are saying that solely based on anecdotal experiences. People report all sorts of things, i.e. shakti stones and cable lifters making audible difference for their stereo setup. You would say not to assume that they are necessarily imagining things, right?
You are still reading my post. Whatever happened to your claim, "you are back on my ignore list"
You mean the audio business that you described as "You on the other hand are a dishonest audio businessman in the room treatment and room EQ business" but couldn't mention a company name or one example of room treatment / EQ product but chose to pick on my diy tube amp? You still haven't responded when I confronted you on this. https://www.diyaudio.com/community/threads/cd-playback-and-dac.354754/page-3#post-6215882
Some guy on the Internet said...
Ffs sake, did he bother to show his measurements or workings out, or explain how the rf coupled through the transformer, diodes, psu caps and following regulation stages... no course he didn't because he doesn't really exist outside the vapid imagination of fantasists.
Ffs sake, did he bother to show his measurements or workings out, or explain how the rf coupled through the transformer, diodes, psu caps and following regulation stages... no course he didn't because he doesn't really exist outside the vapid imagination of fantasists.
If your equipment power supply is so terrible it is unsuited to plug into the mains, throw it out and get a decent bit of kit. No excuse these days. I blame anyone using a toroid transformer and not including a DC blocker incompetent. Same with rudimentary surge suppression and RF suppression. One MOV, one cap. If you are so price sensitive you can't, you should be using a cheaper E-core anyway. Really, any external power conditioner is only a band aid for bad design. Instead of buying bad design and an expensive band aid, just buy/build better stuff to start with. And it does not include a magic cord.
I did not suggest blindly swapping parts in a crossover. Crossover parts are expensive, which is why all but the most exotic are cheaper than the designer probably wanted. In DIY, we can add that tweeter low pass. We can swap out that iron core. Add that zobel to make the amp happier. Deal with a too low tweeter crossover or a metal cone not crossed steep enough. Sure the designer knew about the coil resistance, but that does not make it optimal. I am talking proper design and improvements. Measure, model, prototype, measure, rinse lather and repeat. Cost? You can DIY a capsule mic and with any PC with a sound card do what half a million dollars could not when I started in the hobby. Even the free mic you probably have that came with your AVR is good enough. Here is a hint. You can listen to 10 amps or 10 DACs and split hairs with the difference, but just try and find two speakers that are remotely close even in a walk by! Huge opportunity!
I did not suggest blindly swapping parts in a crossover. Crossover parts are expensive, which is why all but the most exotic are cheaper than the designer probably wanted. In DIY, we can add that tweeter low pass. We can swap out that iron core. Add that zobel to make the amp happier. Deal with a too low tweeter crossover or a metal cone not crossed steep enough. Sure the designer knew about the coil resistance, but that does not make it optimal. I am talking proper design and improvements. Measure, model, prototype, measure, rinse lather and repeat. Cost? You can DIY a capsule mic and with any PC with a sound card do what half a million dollars could not when I started in the hobby. Even the free mic you probably have that came with your AVR is good enough. Here is a hint. You can listen to 10 amps or 10 DACs and split hairs with the difference, but just try and find two speakers that are remotely close even in a walk by! Huge opportunity!
Torroids don't have to be designed so they need DC blockers and or RF input filter caps. It just costs more to make them right. You can end up spending more money on fixes for cheap torroids.
Actually, what I object to here is that the very people who appear to be claiming they know better than everyone else don't know enough to know how little they really know. Best not to be too smug or overconfident. No problem with sharing hints to help fix stuff though.
Regarding Mr.Harmonics, he is the one who likes to make false claims that other people are trying to sell stuff or are paid shills. If that's allowed then I guess anyone can make any claim against him too. Knowing how he is likely to respond to this, I will say that I have expressed opinions about designs by friends that have never been offered for sale. There is nobody here who can say I have tried to sell them anything either (other than two Rohm dac chips I sold for 25% of what they cost me).
Actually, what I object to here is that the very people who appear to be claiming they know better than everyone else don't know enough to know how little they really know. Best not to be too smug or overconfident. No problem with sharing hints to help fix stuff though.
Regarding Mr.Harmonics, he is the one who likes to make false claims that other people are trying to sell stuff or are paid shills. If that's allowed then I guess anyone can make any claim against him too. Knowing how he is likely to respond to this, I will say that I have expressed opinions about designs by friends that have never been offered for sale. There is nobody here who can say I have tried to sell them anything either (other than two Rohm dac chips I sold for 25% of what they cost me).
Anyway, the point is before one jumps into making mods, think about what you are doing. Really, that's all.
There was a great picture and caption in an old book on race car design. Picture of a McLaren CAN-AM car. Caption was something like: " So you think you can do better"
People have over the years, but it is not easy as they knew what they were doing.
There was a great picture and caption in an old book on race car design. Picture of a McLaren CAN-AM car. Caption was something like: " So you think you can do better"
People have over the years, but it is not easy as they knew what they were doing.
Did you read his 3 volume autobiography? ? A fantastic history about a time after the war when we had the notion we could do anything and no one was stopping us, so we did. Cars aside, a great read about people and times. Even my wife loved it.
If you wrote a script on his life, no studio would by it as it is unbelievable. But, that was Smokey.
A lesson he teaches is to think. Think from other disciplines or pull it out of the air. Think about where others have failed. Dis they miss something. This applied to all endeavors from race cars to DIY audio.
If you wrote a script on his life, no studio would by it as it is unbelievable. But, that was Smokey.
A lesson he teaches is to think. Think from other disciplines or pull it out of the air. Think about where others have failed. Dis they miss something. This applied to all endeavors from race cars to DIY audio.
There's a name for that: https://en.wikipedia.org/wiki/Dunning–Kruger_effect
But in general I'm with the OP, understanding the original design and choices made, including compromises, should be the proper starting point for any considered modifications.
McLarens are rare in audio as they are on the road though. For all the flack Amir takes, ASR's measurements of common consumer audio do much to remedy the impression of an industry controlled by highly skilled and motivated engineers in the relentless pursuit of excellence.