| Bronze heatsinks, split from advanced GainClone thread - Click HERE for Original Thread |
| Upupa Epops |
| Bronze is the best material for tower bells...but for heatsink ? How do you mean it, that is sonically better, Peter ? ;) |
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| protos |
| Duuhh, the music is clear as a bell I guess!!:D |
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| poobah |
Anyone care to explain why bronze is sonically better?
:xeye: |
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| Upupa Epops |
| In oposite to copper is bronze free machining.... ;) |
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| meaghers |
I am a beginner here in every sense of the word. I am confused as to how different heatsink materials can (as you propose) affect the sonic characteristics of the opamp. Could someone explain this to me or provide a link to a place where I could read about this?
Peter, the amp looks great and is beyond me in many aspects. I look forward to researching it more in a few years. Keep up the good work! |
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| poobah |
Hi Upupa,
Anyone got an answer??? |
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| Upupa Epops |
| Make diamond heatsink - it have good thermal conductivity and will be probably the best ( except price, certainly... ) :D |
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| pinkmouse |
We could sit and argue heatsink audibility for days, and get nowhere. But I think we can all agree that once again, Peter's construction is top notch, and his design is perfectly pitched for his intended market.
Let's wait and see what the reviews say, I'm sure it will be on 6moons in the near future. ;) |
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| karma |
my guese
heat transfer, electrical field, grounding.
when the moon is in line with the earth:D
i have found using types of metals as a heatzinc changes the sound but very little. its all the little things that makes a good amp;) |
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| Peter Daniel |
I don't have any immediate plans to turn it into commercial product. I just wanted to share a design, that was started almost a year ago.
I don't care much what are the reasons for bronze to sound better or doing research what is written on that subject. I just built 4 different heatsinks (aluminum, copper, brass and bronze) and my choice went to bronze.
If Upupa is willing to donate diamond, I wouldn't mind testing it either. |
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| agent.5 |
| quote: | | I just built 4 different heatsinks (aluminum, copper, brass and bronz) and my choice went to bronze. |
what about gold and silver? With the rising gold and silver prices, the gold heatsinked amp may go up in value every day. |
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| Peter Daniel |
It is too expensive.
BTW, all the standoffs I'm using now are made of bronze as well. How about gold and silver? |
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| jneutron |
| quote: | Originally posted by poobah
Anyone care to explain why bronze is sonically better?
:xeye: |
1. The thermal diffusivity of bronze is lower than that of copper. This means that a heat pulse from the output die will not be able to form a large thermal gradient under the die. This reduces the stick-slip motion at the thermal interface. This lack of stiction frees up the musicality, regardless of the instrument involved.
2. The lower temperature gradient reduces the von mises stresses on the surface, which lowers the distortion of the surface under the die. This lowers listening fatigue, as well as die fatigue.
3. Bronze has a higher modulus, with a little less mass, lower heat capacity, which means that acoustic/thermal compressions will dampen out faster. Transients will be clearer and faster.
4. Lower electrical conductivity means the skin depth will be further down, this will drop the inductance/frequency equation to a flatter response, meaning that eddy current generation will be consistent across the audio bandwidth. (anybody wanna talk about your black background??)
Well.....how'd I do?? :angel:
And, only five days early...couldn't resist.
Seriously though..is that how the wires are going to be dressed in the final units?? Wow, they're just goin everywhere, total anarchy...no e/m logic...
Nice machining though..
Cheers, John |
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| karma |
If Upupa is willing to donate diamond, I wouldn't mind testing it either
would this fit;) |
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| Peter Daniel |
| quote: | Originally posted by jneutron
1. The thermal diffusivity of bronze is lower than that of copper. This means that a heat pulse from the output die will not be able to form a large thermal gradient under the die. This reduces the stick-slip motion at the thermal interface. This lack of stiction frees up the musicality, regardless of the instrument involved.
2. The lower temperature gradient reduces the von mises stresses on the surface, which lowers the distortion of the surface under the die. This lowers listening fatigue, as well as die fatigue.
3. Bronze has a higher modulus, with a little less mass, lower heat capacity, which means that acoustic/thermal compressions will dampen out faster. Transients will be clearer and faster.
4. Lower electrical conductivity means the skin depth will be further down, this will drop the inductance/frequency equation to a flatter response, meaning that eddy current generation will be consistent across the audio bandwidth. (anybody wanna talk about your black background??)
Well.....how'd I do?? :angel:
And, only five days early...couldn't resist.
Seriously though..is that how the wires are going to be dressed in the final units?? Wow, they're just goin everywhere, total anarchy...no e/m logic...
Nice machining though..
Cheers, John |
Thanks for explaining bronze advantage, I didn't have nerve to do that.
Regarding the wiring, only the section between two transformers is organized for now. The other connections are still under testing, so I didn't put any effort in arranging them. Although, after looking inside the Blowtorch preamp, I may actually leave them like that;) |
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| jimbo1968 |
| quote: | Originally posted by Peter Daniel
I don't care much what are the reasons for bronze to sound better or doing research what is written on that subject. I just built 4 different heatsinks (aluminum, copper, brass and bronze) and my choice went to bronze. |
Out of interest, how did you test them?
. |
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| Upupa Epops |
| Best heatsink is box with " dry ice " ( CO2 ).... ;) |
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| poobah |
| quote: | | I am a beginner here in every sense of the word. I am confused as to how different heatsink materials can (as you propose) affect the sonic characteristics of the opamp. |
You're probably better off to remain confused. The claims of sonic superiority are very questionable. However, the use a copper based (bronze, brass) heat spreader is reasonable; provided that the thermal junction between the spreader and the balance of the heat sink is made properly. With the cost of copper (and zinc... used to make brass) rising, coupled with the poor machining qualities of pure copper as Upupa mentioned; the lower cost of bronze would be a "sound" choice...
;) |
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| agent.5 |
| quote: |
Well.....how'd I do?? :angel: |
I think you need more adjectives and compound words. |
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| jneutron |
| quote: | Originally posted by agent.5
I think you need more adjectives and compound words. |
Sorry, I don't have the hang of it yet, I took english as a second language. What's an adjective?? Aren't compound words used to rub out bad words??
Cheers, John |
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| poobah |
Good work John... always a holophonic delight!
:cool: |
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| Upupa Epops |
| Bingo ! And promotional slogan : " In bronze age was sound more sweeter, 'cos electrons was younger ... " :cool: |
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| agent.5 |
| quote: | Originally posted by jneutron
Sorry, I don't have the hang of it yet, I took english as a second language. What's an adjective?? Aren't compound words used to rub out bad words??
Cheers, John |
well I was thinking those big, meaningless, open-ended, subject-to-interpretation descriptions used in Stereophile Magazine to justify the ridiculous, expensive, obscene prices. |
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| jneutron |
| quote: | Originally posted by poobah
Good work John... always a holophonic delight!
:cool: |
I should probably limit "april fool" posts to april 1, and not refer to it five days in advance..
Well, I learned..
Cheers, John |
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| darkfenriz |
Heatsink sonics?
Guys, you are crazy.
Didn't mean to offend, just feel moral need, that someone had to tell that.
I keep reading about different pieces of an amplifier sounding like this and that... fuses, cables, enclosures, heatsinks, mica/silicon washers... has any of you experimenters examined the sonics of frequency compensation circuits of any amp? Like go from undercompensated (read: ringing) through so-believed optimum time-constant to overcompensated (read: slew limited) ?
Hmmm......?? |
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| agent.5 |
| quote: | Originally posted by Upupa Epops
Bingo ! And promotional slogan : " In bronze age was sound more sweeter, 'cos electrons was younger ... " :cool: |
But some aging is mandatory. We need no Michael Jackson here. |
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| dsavitsk |
| quote: | Originally posted by Peter Daniel
I don't care much what are the reasons for bronze to sound better or doing research what is written on that subject. |
That's just depressing. |
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| Peter Daniel |
| quote: | Originally posted by dsavitsk
That's just depressing. |
Explain |
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| PeteM |
| Can someone explain how any heatsink material is better than the material the die is mounted on. |
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| dsavitsk |
| quote: | Originally posted by Peter Daniel
Explain |
Maybe others don't agree with me on this, but for me the spark that makes this hobby interesting and fun is reaching a deeper understanding of how it all works. Without that, you might as well go to the stereo store and try a bunch of brands of equipment without understanding the distinctions between them. So, I took your comment as saying that you really were just throwing a dart blindfolded and hoping for the best. I don't necessarilly care which material is the best as that's boring. I care why one is the best. This is DIY after all. If you just give me the answer without teaching me anything, then I am not really any better off.
The design is nice, b/t/w/ I wish my own wood/metal working skills were even half of yours.
-d |
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| darkfenriz |
| quote: | Originally posted by dsavitsk
If you just give me the answer without teaching me anything, then I am not really any better off.
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This is wise attitude.
How about answers to questions that you would never ask?
At least I wouldn't. I remember being once told by a world class physicist "The greatest quest is to be able to tell sense from nonsense". Simple words but much meaning. Back to topic I could find some reasons for 0.1K/W heatsink being better than 10k/W and otherwise, but sonics of the heatsink material is nonsense. I am sorry for that. Now I will 5HU+ up as I told everything I wanted.
regards |
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| dsavitsk |
| I don't know, I think I could believe that the temperature stability of the chips could matter, and that different sinking materials could maintain that stabity better than others. I certainly find that warmed up opamps sound better than when they are first switched on. But, I do think that the burden of poof is pretty high here. |
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| Peter Daniel |
| quote: | Originally posted by dsavitsk
Maybe others don't agree with me on this, but for me the spark that makes this hobby interesting and fun is reaching a deeper understanding of how it all works. Without that, you might as well go to the stereo store and try a bunch of brands of equipment without understanding the distinctions between them. So, I took your comment as saying that you really were just throwing a dart blindfolded and hoping for the best. I don't necessarilly care which material is the best as that's boring. I care why one is the best. This is DIY after all. If you just give me the answer without teaching me anything, then I am not really any better off.
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I look at that in a different way: I don't need to know how engine works to be able to drive a car, I don't need to know how SACD works in order to enjoy the sound.
For me, the spark that makes this hobby interesting is creativity I find within myself. The creativity that allows me to create devices that are recognized and hold their ground in comparisons with other.
If you took my comment that I "were just throwing a dart blindfolded and hoping for the best" you must be pretty new to this forum and then you shouldn't be commenting in such careless way.
I don't care why the given material sounds the best, most of the folks in the world don't know the answer. What I care about is how it sounds, and to decide about that I already spent 4 years experimenting with different chassis materials, resonanses control, structural design and heat dissipation.
I'm not here to teach you anything. Being the member of that forum you should consider yourself lucky that I care enough to actually show anything. If you don't know how to utilize that information it's not my problem, it can only be yours. I don't need to explain myself in any way.
But putting judgement on people in such careless way certainly does not spark any interest in that hobby.
What I find depressing, is that soon, along with changing forum logo, the forum motto will be also changed and we will be looking at:
diyAudio
place where fanatics don't post anymore
What I find depresing is that some folks really need to know why, before they actually decide to try something. |
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| jleaman |
| quote: | Originally posted by Peter Daniel
What I find depressing, is that soon, together with changing the forum logo, the forum motto will be also changed and we will be looking at:
diyAudio
place where fanatics don't post anymore
What I find depresing is that some folks really need to know why, before they decide to try anything. |
Why would you say this ? |
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| Peter Daniel |
| Read the whole thread and you will know why. |
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| metalman |
| quote: | Originally posted by jneutron
I should probably limit "april fool" posts to april 1, and not refer to it five days in advance. |
Dang John, you took away all my fun. For a second there I thought you were serious, and I had already pulled out my Thermodynamics / Heat Transfer references to provide a technical rebuttal. Got myself all spooled up for a good debate just to have it evaporate before I could join in.:clown:
Cheers, Terry
P.S. Lower thermal diffusivity and lower specific heat values would increase the thermal flux at the heatsink, not decrease it. Just couldn't resist! :devilr: |
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| poobah |
"Fanatic" is a word that perhaps should not be confused with "lunatic"... sometimes similar, but often different...
Why not just say that bronze is cheaper and easier to machine? Leave all the sonic nonsense out?
:xeye: |
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| jleaman |
| quote: | Originally posted by Peter Daniel
Read the whole thread and you will know why. |
I guess, But what picture is every one referring to ? |
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| pinkmouse |
| Thread split from here. |
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| Peter Daniel |
| quote: | Originally posted by poobah
Why not just say that bronze is cheaper and easier to machine? Leave all the sonic nonsense out?
:xeye: |
Where I live, bronze its at least double the copper cost. Machining is not an issue here. |
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| PauSim |
| quote: | Originally posted by Peter Daniel
What I find depressing, is that soon, along with changing forum logo, the forum motto will be also changed and we will be looking at:
diyAudio
place where fanatics don't post anymore
What I find depresing is that some folks really need to know why, before they actually decide to try something. |
Bravo!
:smash: |
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| metalman |
Dang nabbit! I realized I didn't say it right. The thermal flux does decrease, but the thermal gradient does increase in response to a thermal pulse. Not that anyone actually cares, but I hate leaving my mistakes uncorrected. Less embarrasing than having someone else correct me later!:D
As much as I hate to say it, brass does have a scientifically documented benefit over copper for vibration and resonance control. Lubricity is only one of several reasons whey bronze is a favoured material for large scale industrial bearings.
Cheers, Terry |
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| tomtt |
seems a lot of japanese diyers are using brass, bronze, and
granite, in systems, for 'dead mass'.
would granite make a usable heatsink? |
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| Eva |
What a tremendous ability humans have to waste prime materials
:bigeyes:
It's really discouraging to see people building randomly and being proud of it. |
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| redunzelizer |
| quote: | Originally posted by Peter Daniel
What I find depresing is that some folks really need to know why, before they actually decide to try something. |
Yes, It's DO-It-Yourself. But different peeps not only will DO things different, also their *approach* to a certain subject is very individual. *Each* of these approaches is valid. Period.
With condemning others for doing analysis and gaining a better understanding, probably carefully sorting out choices before even touching the materials, you, Peter, might leave a very ignorant and narrowminded impression.
That's what I would find depressing, someone telling me how and if to think...
regards |
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| tomtt |
i saw this movie, at a theater, after, i was so depressed,
the next day,bought a-lot 'o Cr-4p at numerus thrift stores,
and some caps' n' perf board just to get feellin better.
http://www.imdb.com/title/tt0065571/
````````````````````````````````````
All Our Products Now Come Infused With 'Cr-4p' |
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| Upupa Epops |
| Sound of heatsinks ? Do you really mean it seriously ? :D I'm curious, what will be your next " experience " .... Sound of PCB ? Sound of power station ? Sound of maple ? Or what ? ;) I'm wailing.... |
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| Elso Kwak |
Thermal resistance?
:rolleyes: |
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| Elso Kwak |
| quote: | Originally posted by Upupa Epops
Sound of heatsinks ? Do you really mean it seriously ? :D I'm curious, what will be your next " experience " .... Sound of PCB ? Sound of power station ? Sound of maple ? Or what ? ;) I'm wailing.... |
Yeah, yeah round the sharp corners of the PCB, pour some laquer over it, C37? Teflon sounding better than epoxy or poly iso-cyanate ester? Or better p2p wiring? It is up to you! Life and engineering is about choices you know ;)
BTW I have a can of Maple juice. What should I do with it?
:cool: |
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| dfdye |
| quote: | Originally posted by tomtt
would granite make a usable heatsink? |
Short answer: No. |
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| Elso Kwak |
| quote: | Originally posted by dfdye
Short answer: No. |
Short explanation: high thermal resistance
:cool: |
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| dfdye |
WARNING: CONSTRUCTIVE POST!!!!! Some may wish to disregard this post! :D
Quick question for Peter if you are still keeping up with this thread: what brass alloy are you using for the heatsink? Also, what thermal paste or pads are you using? (I think those look like silicon pads, but I wanted to ask.)
I must admit that I am not sold on the "sound of heatsinks," but whether it sounds any different or not, it definitely looks great! So I figured I would try and see for myself how it works/sounds since I have a stash of brass sitting around. :D
Thanks for sharing! |
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| AudioFreak |
| quote: | Originally posted by dfdye
Also, what thermal paste or pads are you using? (I think those look like silicon pads, but I wanted to ask.)
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If memory serves correctly, Peter uses beryllium oxide (tsk! tsk!) and then coats it on both sides with silicon grease. |
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| peranders |
I have a good material for heat transfer. It's an insulator and conducts heat better than silver. Which material? :idea: I'll let you think about this for a while. :nod:
I don't know what Peter really thinks but bronze and brass are very nice materials to work with, much nicer than copper. |
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| jimbo1968 |
I am wondering if the material is irrelevant but the chip temperature is the factor.
This would/could lead to a different conclusion on 'best' material for every amp/speaker configuration.
I note that many designs (including Peter's) look 'under heatsinked' to my novice eyes. Maybe the secret is keeping the chip at just the right (high) temperature. |
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| karma |
| with all the holes im sure it works good. and if you look at the pic you can see the front faceplate and back has heatzinc grease so really the hole amp works as a heatzinc. just not the sides;) |
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| jimbo1968 |
| maybe all the components like a nice warm working environment. |
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| Elso Kwak |
| quote: | Originally posted by jimbo1968
maybe all the components like a nice warm working environment. |
I for one like the climate in Greece or the Filipines much more than in UK.
:D |
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| komen |
| quote: | I am wondering if the material is irrelevant but the chip temperature is the factor.
This would/could lead to a different conclusion on 'best' material for every amp/speaker configuration.
I note that many designs (including Peter's) look 'under heatsinked' to my novice eyes. Maybe the secret is keeping the chip at just the right (high) temperature. |
This sounds like really sound explanation to me. But in this case we would have different best heatsink for each volume level also.
Solution could be using thermistor to measure chip or heatsink temperature and use active heating/cooling to adjust that temperature. Has anyone tried this or interested enough to try? This kind of equipment would give nice possibility to compare same chip in different temperatures. |
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| setmenu |
| quote: | Originally posted by Eva
What a tremendous ability humans have to waste prime materials
:bigeyes:
It's really discouraging to see people building randomly and being proud of it. |
I guess it depends on your approach to the hobby and the reasons for doing it.
As a sculptor I might just use a material because I like it and for no other logical reason.
Most things people want , have or desire are not necessities of life.
If anything hobbyists tend to recycle thrown out material or products more so than 'mere' consumers.
I would guess the best way to be kind to the earths resources
would be to cull most of the earths human population and have
the remainder return to living in the proverbial mud huts.;)
That said, I do understand what you are getting at as there is a
lot of wasteful consumption of finite resources happening on this
planet.:(
Mark |
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| poobah |
| quote: | | Comparison between all those heatsinks isn't certainly an easy one. Maybe you remember that my first monoblock amp was using large copper piece acting as heatsink and structural bar. Initially, I liked the sound, but after CES, we came to conlusion that the air was somewhat missing in that amp. I was also using a clamping bar to attach the chip to the heatsink. After removing that calmp and replacing it with a regular screw things improved, but eventually we decided for aluminum heatsink as it provided more air extention, with copper it was a bit less. Those are not only my observations, but also from the people who worked with me while developing the amp. |
it gets better...
| quote: | | I later built the first Patek using bronze and I found that that material provided nicely balanced sound: it was less zingy and harsh than aluminum, but didn't damp higher frequencies as much as copper. It seemed that the sound gained more refinement as well. |
and better...
| quote: | | Brass also worked well, but somehow I didn't feel convinced about using it, I'm not sure why, maybe because of the qualities of the metal iself. |
and better still...
| quote: | | The amount of damping and air extention will depend on the mass of the heatsink and cannot be easily estimated untill tried in an actual design. It will also depend how the hetasink is attached and supported. |
Now I understand...
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| jimbo1968 |
| quote: | Originally posted by karma
maybe thay do. if its anything like the patek it will have a Perforated Aluminum top. |
according to my theory, Peter should be able to tune the amp with different size perforations. |
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| jimbo1968 |
| quote: | Originally posted by komen
This sounds like really sound explanation to me. But in this case we would have different best heatsink for each volume level also. |
We are lucky, the dissipation curve versus output power is quite flat.
| quote: | | Solution could be using thermistor to measure chip or heatsink temperature and use active heating/cooling to adjust that temperature. Has anyone tried this or interested enough to try? This kind of equipment would give nice possibility to compare same chip in different temperatures. [/B] |
Once we have established the optimum temperature there are many possibilities.
I quite fancy bi-metallic surfaces that open and close, a sort of breathing amplifier. |
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| karma |
| quote: | Originally posted by jimbo1968
according to my theory, Peter should be able to tune the amp with different size perforations. |
if you can prove it be sure to post it here.
heh i was thinking more on the lines of ventilation
;) :rolleyes: |
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| jimbo1968 |
| quote: | Originally posted by karma
if you can prove it be sure to post it here
;) :rolleyes: |
I eagerly await Peter's confirmation of my theory.
My own testing will have to wait until I've eliminated a few more basic things like hum and oscillation. |
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| GG |
| quote: | Originally posted by jimbo1968
I am wondering if the material is irrelevant but the chip temperature is the factor.
This would/could lead to a different conclusion on 'best' material for every amp/speaker configuration.
I note that many designs (including Peter's) look 'under heatsinked' to my novice eyes. Maybe the secret is keeping the chip at just the right (high) temperature. |
Temperature would be the only logical guess as to how a heat sink (material) could affect quality of sound. However, if that is the case, there would be no 'best' heat sink material for sound, rather it would be any heat sink that could maintain the chip at the optimal temperature for best sound quality. But considering that quality of sound is person dependent, this could be a never ending and is already a pointless debate.
It seems funny (in a sad way) that the bronze heat sink has generated more buzz than the amp. It seems clear that advertising the superior sonic capabilities of a heat sink is a poor marketing idea for amplifiers.
Gio. |
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| Bas Horneman |
A lot of people are sceptical about the properties of certain materials when relating to sound. And I don't blame them. I will not say anything for or against that kind of approach because I simply have not studied it.
But let's put it this way. Each metal does have unique damping characteristics. This is scientifically accepted no?
The type of insulation used for a conductor of electricity also has an influence on the sound. (Accepted by I suppose a large part of the audiophile community. This is I suppose not scientifically "provable" )
The type of metal used as a conductor also has an influence on sound. (Even when taking capacitance,resistance and inductance into consideration) (This once again is only accepted by a part of the audiophile community) But once again this cannot be proven by science I believe.
Which brings me to my point.
There are 2 stances to be taken IMO. Either these "phenomenon" don't exists. Or we don't know what to measure or can't measure them.
Either science is not advanced enough to explain the influence of natural materials near an electric/magnetic field or conductor. Or materials near a conductor or electric/magnetic field simply don't have an influence on sound. I believe that either could be the case. But there is simply no way I would dismiss either of the 2
"camps". Because I accept that there might be more to it than we know at the moment. |
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| Peter Daniel |
| quote: | Originally posted by dfdye
what brass alloy are you using for the heatsink? Also, what thermal paste or pads are you using? (I think those look like silicon pads, but I wanted to ask.)
I must admit that I am not sold on the "sound of heatsinks," but whether it sounds any different or not, it definitely looks great! So I figured I would try and see for myself how it works/sounds since I have a stash of brass sitting around. :D
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The alloys I'm using are the ones available from Metal Supermarkets, there is not much choice there and there is only one available for brass and few for bronze. I used the softer alloy for bronze, but don't know what specific type it is.
Thermal paste is nothing special, Thermalcote from Thermalloy. I'm not using any pads under the chips, as two years ago I switched to insulated package. I noticed it sounded better than non insulated with pads. At that time I was using indeed aluminum and beryllium oxide pads with compound.
| quote: | Originally posted by jimbo1968
I am wondering if the material is irrelevant but the chip temperature is the factor.
I note that many designs (including Peter's) look 'under heatsinked' to my novice eyes. Maybe the secret is keeping the chip at just the right (high) temperature. |
Actually, it seems to me that the chip sounds better with lower temperatures. |
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| SY |
| quote: | | This is I suppose not scientifically "provable" |
Yes it is. It just hasn't been. |
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| Peter Daniel |
| quote: | Originally posted by GG
Temperature would be the only logical guess as to how a heat sink (material) could affect quality of sound. However, if that is the case, there would be no 'best' heat sink material for sound, rather it would be any heat sink that could maintain the chip at the optimal temperature for best sound quality. But considering that quality of sound is person dependent, this could be a never ending and is already a pointless debate.
It seems funny (in a sad way) that the bronze heat sink has generated more buzz than the amp. It seems clear that advertising the superior sonic capabilities of a heat sink is a poor marketing idea for amplifiers.
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I don't think it is related to temperature, as I mentioned already, when the heatsink gets really hot the amp does not sound better than when it's cold.
There were many previous discussions on that forum with regards to material properties and their influence on the sound, here's one: http://www.diyaudio.com/forums/show...t=&pagenumber=1 BTW, I'm presently using air suspension table under my CD transport that was mentioned in a linked thread.
As Upupa touched already the subject of sound of Maple, I may add, that at one time I was experimenting with different pieces of wood under the footing of the amp (cones). Each wood was affecting sound signature slightly, to the point that one could tune it in a similar way it's done with interconnects. Replacing wood with metal pieces or polycarbonate brought even bigger changes to the sound.
IIRC, there is at least one high end manufacturer that supports using myrtle blocks as footing for the equipment.
It's indeed peculiar that the main focus of disussion goes to the heatsink material, the element of design that actually has least importance here. I just learned I need to be more carefull with wording next time and don't mentione everything. One never knows what crowd he will be dealing with;) |
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| GG |
| quote: | Originally posted by Peter Daniel
It's indeed peculiar that the main focus of disussion goes to the heatsink material, the element of design that actually has least importance here. I just learned I need to be more carefull with wording next time and don't mentione everything. One never knows what crowd he will be dealing with;) |
Agreed. Peculiar focus and no agrument that people are strange.
BTW - your chassis skills are exceptional. If mine were anywhere close to as good as yours, I would have to buy new furniture so my amps would not stick out. Keep up the good work.
Gio. |
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| Bas Horneman |
| quote: | | Yes it is. It just hasn't been. |
LOL. |
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| Upupa Epops |
| As I see in the end, many people think, that amp is " musical instrument ", which can be tuneable like guitar by various exotic material... By these experiments they have feeling like Stradivari... :D They know nothing about physic, most important is to think up theory for reasoning.... This prism with holes have interesting design, but as heatsink is it for nothing, 'cos for " vent stack " have it too small diametres and is free, which material is used..... |
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| Peter Daniel |
| quote: | Originally posted by Upupa Epops
As I see in the end, many people think, that amp is " musical instrument ", which can be tuneable like guitar by various exotic material... By these experiments they have feeling like Stradivari... :D They know nothing about physic, most important is to think up theory for reasoning.... This prism with holes have interesting design, but as heatsink is it for nothing, 'cos for " vent stack " have it too small diametres and is free, which material is used..... |
You touched the subject of PCBs as well, and now the exotic materials. From our previous conversations, I got impression that you kept Madrigal in the realm of sound engineering practises and no gimmicks. Here's what they say about exotic materials and tuning an electronic device in a way similar to musical instrument: |
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| Upupa Epops |
| It is mostly only promotional blables, Peter... Less absorbtion of moisture is not interesting for normal people, if aren't living in rain forest... ;) BTW, at ML : on one side similar blables and on other side using of OPA 604, which is not so perfect opamp.... |
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| Peter Daniel |
| quote: | Originally posted by Upupa Epops
This prism with holes have interesting design, but as heatsink is it for nothing, 'cos for " vent stack " have it too small diametres |
Actually, the holes are not there for looks and I'm aware that some of them are too small for ventilation, but that's what experimentation is all about.
The bronze heatsink was initially much bigger and had only one row of holes in a center. Initial using indicated that this is not the best approach. Because of low thermal conductivity and high mass, the bronze piece didn't work as heatsing but as a heat tank, accumulating thermal energy but not relasing it (the two adiitional copper panels are supposed to release the heat from bronze).
Later, I decided to reduce the "heatsink" mass and storage capacity, that's why those additional smaller holes. It works better now, but still not efficient as I wished.
I might consider adding additional metal plates between two copper panels. That will both improve shielding and increase the dissipating surface.
After changing the shape of bronze piece, I noticed slight difference in sound as well. So it's not only the material itself, but also mass and shape. |
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| Peter Daniel |
| quote: | Originally posted by Upupa Epops
BTW, at ML : on one side similar blables and on other side using of OPA 604, which is not so perfect opamp.... |
Remeber, it was 1994 ;)
The upraded, S versions, were using better chips too. |
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| poobah |
That's like using quotes from the Bible to prove other quotes from the bible. It's just nuts... proof should lie in extrinsic cooboration... not intrinsic... nuts.
sonic signature of wood...
:smash: |
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| Elso Kwak |
| quote: | Originally posted by poobah
That's like using quotes from the Bible to prove other quotes from the bible. It's just nuts... proof should lie in extrinsic cooboration... not intrinsic... nuts.
sonic signature of wood...
:smash: |
I like sandal wood; dunno why.......
:)
The sound maybe? |
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| jneutron |
| quote: | Originally posted by metalman
Dang nabbit! I realized I didn't say it right. The thermal flux does decrease, but the thermal gradient does increase in response to a thermal pulse. Not that anyone actually cares, but I hate leaving my mistakes uncorrected. Less embarrasing than having someone else correct me later!:D |
You are spending an awful lot of time on that stuff, now ain't ya??? I must admit, I did pull most of it from where the sun don't shine, but it is stuff I use everday.
Thermal diffusivity is a function of thermal conductivity and heat capacity. The more conductive, the higher the diffusivity. The lower the heat capacity, also the higher the diffusivity.
Copper at 4.5 Kelvin has incredibly high diffusivity, for example. This is because it's thermal conductivity remains the same (relatively) as it is at room temp, but it's heat capacity drops 2 to 3 orders of magnitude..heat flies through it at liquid helium temperatures.
Cheers, John
PS...ok, I admit...I woulda had fun wit youzes errahs.. |
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| poobah |
| John you left out the equation... units would be nice too! |
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| agent.5 |
| WOW. 9 pages already. Maybe it is time to arrange a heatsink shootout. |
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| jneutron |
In the old days, when dinosaurs ruled the world, most of the packaged silicon was put into non isolated packages. Kovar (magnetic), aluminum (god forbid), and now, for the most part, copper.
The isolated packages have a plastic layer on the bottom of the copper, and this has low thermal conductivity, essentially forcing the die to act as an isothermal island. This can be good for high power devices, as it lessens the thermal gradients which can form across the die. It does, of course, impact derating.
There are significant differences between the isolated and non isolated packages..It is unknown if those differences show as sonic, but one cannot easily brush the possibility aside.
Capacitance is changed. Thermal pulse response is changed. Indeed, proximity of the heatsink to the silicon die changes the system inductance as well as the coupling between the output currents and the input gain stages.
I can figure out at least three ways changing the heatsink material could conceivably alter the transfer function of an "all in one silicon die"..
Vibrational aspects are not one of them. Skin depth, thermal diffusivity, and thermal conductivity certainly, but not what I would consider silly.
The fact that someone reports a diff, well..are we all so sure? I'm not.
Cheers, John |
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| jneutron |
Thanks for the link.
It is a shame that on the first page is a big glaring error.:bawling: :smash:
Look at the picture of the packaged die..lower left hand side of the first page..
They drew the die with the die bottom surface on the same plane as the package case bottom????
That doesn't happen. They shoulda drawn the package base thickness there, as the die is soldered to that base. Typically, this thickness is about 40 mils, and increases the effective heat source dimension 80 mils by 80 mils. For die in the sub 250 mil range, this is a significant error component in calculation of thermal resistance from the junctions on the top of the die to the heatsink.
Without this heat spreader, as it were, the calculated heat flux through the insulator will be over estimated, the thermal drop overestimated...life as we know it would end!!!!!!!!!!
Sloppy, shame on them..
Cheers, John (aka, the puppeteer)
ps...of course, my little nitpick tirade has nothing to do with the article's intent...it is a very good article..
pps...I built me one of dem thermal testers, I like the fact that they specify measurement of the parameter of interest, as nuttin generally runs 2.2 mV/degree C. Power diodes generally run from .6 to 1.2 mV/C. I ran up to 100 amps DC, and had the choice of method...eitehr forcing current/measuring temp, or forcing temp with a feedback loop.. It was really neat, a bridge running 45 amperes and then unbolting the bridge from the sink, and watching the machine react by dropping the current.. |
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| Elso Kwak |
| quote: | Originally posted by jneutron
Thanks for the link.
It is a shame that on the first page is a big glaring error.:bawling: :smash:
Look at the picture of the packaged die..lower left hand side of the first page..
They drew the die with the die bottom surface on the same plane as the package case bottom????
That doesn't happen. They shoulda drawn the package base thickness there, as the die is soldered to that base. Typically, this thickness is about 40 mils, and increases the effective heat source dimension 80 mils by 80 mils. For die in the sub 250 mil range, this is a significant error component in calculation of thermal resistance from the junctions on the top of the die to the heatsink.
Without this heat spreader, as it were, the calculated heat flux through the insulator will be over estimated, the thermal drop overestimated...life as we know it would end!!!!!!!!!!
Sloppy, shame on them..
Cheers, John (aka, the puppeteer)
ps...of course, my little nitpick tirade has nothing to do with the article's intent...it is a very good article..
pps...I built me one of dem thermal testers, I like the fact that they specify measurement of the parameter of interest, as nuttin generally runs 2.2 mV/degree C. Power diodes generally run from .6 to 1.2 mV/C. I ran up to 100 amps DC, and had the choice of method...eitehr forcing current/measuring temp, or forcing temp with a feedback loop.. It was really neat, a bridge running 45 amperes and then unbolting the bridge from the sink, and watching the machine react by dropping the current.. |
Yes the package metal is uncredible thin under the die in the picture. Must be a drawing error, as I think it is as thick as the tab there.
I my carreer as a repair tech I replaced so many transistors as they became too hot. Too small heatsink! Also in my Gas Ampzilla pre-drivers became way too hot; crazy! |
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| jneutron |
| quote: | Originally posted by Elso Kwak
Yes the package metal is uncredible thin under the die in the picture. Must be a drawing error, as I think it is as thick as the tab there. |
Yep..that is my experience.
Cheers, John |
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| metalman |
| quote: | Originally posted by jneutron
You are spending an awful lot of time on that stuff, now ain't ya??? I must admit, I did pull most of it from where the sun don't shine, but it is stuff I use everday.
.....
PS...ok, I admit...I woulda had fun wit youzes errahs.. |
My personal favorite was your von Mises reference. Wonderfully obscure! My clue to the sarcasm was that anyone who could reference the von Mises stress criteria pretty much by definition would have to understand it, and for Peters chassis and the temperature differences we're considering, the differential thermal expansions wouldn't come anywhere close to the von Mises stress.
If it weren't for the character limitations here, I'd post the differential equation for solving transient conduction in a semi-finite solid. Then we could build a finite element model and simulate the different materials. Ooh Ooh, who's with me!!! |
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| jneutron |
| quote: | Originally posted by metalman
My personal favorite was your von Mises reference. Wonderfully obscure! My clue to the sarcasm was that anyone who could reference the von Mises stress criteria pretty much by definition would have to understand it, and for Peters chassis and the temperature differences we're considering, the differential thermal expansions wouldn't come anywhere close to the von Mises stress.
If it weren't for the character limitations here, I'd post the differential equation for solving transient conduction in a semi-finite solid. Then we could build a finite element model and simulate the different materials. Ooh Ooh, who's with me!!! |
Thank goodness for character limitations. And I thought I was a sicko..:eek:
Cheers, John;) |
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| poobah |
Could we get back to the sound of bronze???
:smash: |
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| Upupa Epops |
| They can't talk about bronze, Rob... ;) |
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| peranders |
| quote: | Originally posted by Upupa Epops
Sound of heatsinks ? Do you really mean it seriously ? :D I'm curious, what will be your next " experience " .... Sound of PCB ? Sound of power station ? Sound of maple ? Or what ? ;) I'm wailing.... |
Everything sounds according to Peter. You ought to know that by now, Pavel :D hard to argue against that.. |
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| peranders |
| quote: | Originally posted by peranders
I have a good material for heat transfer. It's an insulator and conducts heat better than silver. Which material? :idea: I'll let you think about this for a while. :nod:
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Diamond! This is a very nice material and you don't have to use any insulation material. Diamond heatsinks sound really incredible, don't you agree Peter? :D |
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| SY |
| With some of the new CVD diamond thin film processes, this may not be as farfetched as you think. I could easily imagine a hunk of metal with a diamond film as insulator and thermal coupler. |
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| poobah |
Does anyone know if transparent aluminum will be conductive?... maybe a semiconductor?
I DO know we haven't actually made it yet... but someone knows this stuff.
:xeye: |
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