SY said:
In a street, with sound coming from the first floor window? I wouldn't want to bet a beer that I CAN reliably hear the difference. I have been fooled by myself a few times too many.
Jan Didden
Re: hmmm.
/OT on
If I may go slightly OT here, don't tell me behavioural health care is run scientifically! Don't tell me the drug problem is approached scientifically, it's not. I don't want to ramble on, but look at the prison system. There are tons of studies, mega statistics on crime, nobody really knows where it comes from. The only solution we seem to have is either to kill the guy or put him behind bars. Does it have any effect on crime? None whatsoever. Now if approached scientifically, 100 years ago somebody would have already realised something is wrong: we do all this, with zilch result. Conclusion: we do it wrong. Let's study the problem, and develop a solution. That doesn't happen, we just go on squandering resources with nil result. Same with drugs. If we would have approached technology the way we approach drugs, we would still have hand-pushed carts.
/OT off
Jan Didden
Sawzall said:
/OT on
If I may go slightly OT here, don't tell me behavioural health care is run scientifically! Don't tell me the drug problem is approached scientifically, it's not. I don't want to ramble on, but look at the prison system. There are tons of studies, mega statistics on crime, nobody really knows where it comes from. The only solution we seem to have is either to kill the guy or put him behind bars. Does it have any effect on crime? None whatsoever. Now if approached scientifically, 100 years ago somebody would have already realised something is wrong: we do all this, with zilch result. Conclusion: we do it wrong. Let's study the problem, and develop a solution. That doesn't happen, we just go on squandering resources with nil result. Same with drugs. If we would have approached technology the way we approach drugs, we would still have hand-pushed carts.
/OT off
Jan Didden
Back to the original subject....
I agree with Jonathon Carr that different insulating pads will likely cause differing capacitive coupling to the heatsink and that this may be audible according to the transisent stability of the amplifier circuit.
I also agree that bending moments on the device may cause alteration of chip characteristics.
One other effect in my experience is that of the heatsink material itself.
I have built the same amp design using aluminium or copper heatsinks and this gave two subtly differing sounds - I preferred the copper one.
I think that local field effects are at work here, and by this method I would expect differing insulating pads to cause differing sounds.
Eric.
I agree with Jonathon Carr that different insulating pads will likely cause differing capacitive coupling to the heatsink and that this may be audible according to the transisent stability of the amplifier circuit.
I also agree that bending moments on the device may cause alteration of chip characteristics.
One other effect in my experience is that of the heatsink material itself.
I have built the same amp design using aluminium or copper heatsinks and this gave two subtly differing sounds - I preferred the copper one.
I think that local field effects are at work here, and by this method I would expect differing insulating pads to cause differing sounds.
Eric.
The aluminium heatsink had a clangy harshness about it.
The copper heatsink sounded more friendly and easier on the ear.
The aluminium had more 'detail', but this is false detail in my books.
Eric.
The copper heatsink sounded more friendly and easier on the ear.
The aluminium had more 'detail', but this is false detail in my books.
Eric.
That's a tough one to design an experiment for, so if I were a reviewer, I'd pound on that one as a major factor in the enjoyment of reproduced music.
I'm also still (on my professional end) trying to figure out how to test the claims of some wine glass manufacturers who sell nosebleed-priced stemware that supposedly makes wine taste "better."
Aluminium Used To Be Called 'Congealed Electricity"
I have a high power pro amp that uses copper heatsinks (fan cooled) and this amp has a gentler sonic characteristic than most amps.
I have also seen inside a Denon monoblock amp that used thin copper plates between the output devices and the aluminium heatsinks - this amp sounded rather good to my ear too.
I have been exploring local field effects for some time and let me assure you that local effects due to materials can have a very strong effect, and differing materials add particular sonic characters, and different materials have varying degree of effect.
Peter is voicing his amp by introducing particular materials sounds due to local field effects and not due to vibrations control I expect.
Try this experiment - have the same amp running on the bench and compare sounds with no top cover, aluminum top cover, steel top cover or wood top cover and expect to hear distinctly differing sounds - have I inspired your curiosity yet ?.
This is just the first step to some understanding of this.
Eric.
Congealed electricity
I did not mean according to temperature (summer/winter) but BTW I have heard a respected designer state that he regulates heatsink temperature to a particular temerature (55*C ? from memory) because he reckons this temp sounds best.
I have a high power pro amp that uses copper heatsinks (fan cooled) and this amp has a gentler sonic characteristic than most amps.
I have also seen inside a Denon monoblock amp that used thin copper plates between the output devices and the aluminium heatsinks - this amp sounded rather good to my ear too.
I have been exploring local field effects for some time and let me assure you that local effects due to materials can have a very strong effect, and differing materials add particular sonic characters, and different materials have varying degree of effect.
Peter is voicing his amp by introducing particular materials sounds due to local field effects and not due to vibrations control I expect.
Try this experiment - have the same amp running on the bench and compare sounds with no top cover, aluminum top cover, steel top cover or wood top cover and expect to hear distinctly differing sounds - have I inspired your curiosity yet ?.
This is just the first step to some understanding of this.
Eric.
Congealed electricity
Turn the ship upside down Unk......
If I can stop laughing long enough to type while watching you lunatics run around in circles.......... the usual intelectual and physical laziness. Please do not read this if you are trying to do R and D outside the influence of this forum, particularly if you are later going to claim to have done it this without any ideas from the DIYaudio forum.
If you want to investigate the effect of the capacitance between the heat sink the Power op amp measure it for each insulator and add the delta to the lower capacitance configuration and add a capacitor. The National parts have the tab connected the negative supply. I believe the capacitance will be in the range of a few pF for the case insulator interface heat sink interface and probably not that influential. The capacitance could also be changed by the addition of an external capacitor to investigate this effect independent of the insulator.
I am also dumbfounded by nobody suggesting applying damping to the other side of the op amp to allow further tuning of damping. There are several products to use for this. Marigo audio labs sells some devices and Michael Percy carries several types of EAR damping materials. Mechanical resonant systems can be modeled by the same differential equations as electrical circuits and mass and compliance are analogs of inductance and capacitance. Just as in critical damping for RCL circuits there is and optimum mechanical impedance for damping mechanical resonance. The amount of damping is important as well and mechanical systems can be easily over damped (its damped and not dampened BTW, people who refer to this as dampening are all wet) by using the wrong material or the wrong amount of material. damping materials are very temperature sensitive and should be allowed stabilize to the device operating temperature when evaluating them.
Lead foil should be used very carefully as it often over applied. Soft aluminum (hmmm, like skinned capacitors perhaps....) makes a very good damping material in conjunction with a viscoelastic polymer backing. I will not go into the subjective value judgments of how effective this is, but have supplied enough information for people to play with this effect. Vacuum tubes are pretty sensitive to this even in power amplifier applications. the first stage of phono preamps are critical and I have seen circuit boards mounted on rubber bands in one commercial Nuvistor based MC step up preamp. All of this stuff has been flogged to death for the last 10 years and is old news to everybody (except the people who read this forum it appears) who is a serious audio tweaker. It is amazing how much progress was made without the internet........ who knew?
http://www.percyaudio.com
http://marigoaudio.com/rone.htm
3mm White VTS Tuning Dots
http://www.positive-feedback.com/Issue1/marigovtsdots.htm
http://products3.3m.com/catalog/us/...ytapes_3_0/command_AbcPageHandler/output_html
http://www.earsc.com/CMSFrame.asp?SID=5&exturl=materials/dam.phtml
http://nadcoinc.com/FoilTapes.htm
http://products3.3m.com/catalog/us/...ytapes_3_0/command_AbcPageHandler/output_html
If I can stop laughing long enough to type while watching you lunatics run around in circles.......... the usual intelectual and physical laziness. Please do not read this if you are trying to do R and D outside the influence of this forum, particularly if you are later going to claim to have done it this without any ideas from the DIYaudio forum.
If you want to investigate the effect of the capacitance between the heat sink the Power op amp measure it for each insulator and add the delta to the lower capacitance configuration and add a capacitor. The National parts have the tab connected the negative supply. I believe the capacitance will be in the range of a few pF for the case insulator interface heat sink interface and probably not that influential. The capacitance could also be changed by the addition of an external capacitor to investigate this effect independent of the insulator.
I am also dumbfounded by nobody suggesting applying damping to the other side of the op amp to allow further tuning of damping. There are several products to use for this. Marigo audio labs sells some devices and Michael Percy carries several types of EAR damping materials. Mechanical resonant systems can be modeled by the same differential equations as electrical circuits and mass and compliance are analogs of inductance and capacitance. Just as in critical damping for RCL circuits there is and optimum mechanical impedance for damping mechanical resonance. The amount of damping is important as well and mechanical systems can be easily over damped (its damped and not dampened BTW, people who refer to this as dampening are all wet) by using the wrong material or the wrong amount of material. damping materials are very temperature sensitive and should be allowed stabilize to the device operating temperature when evaluating them.
Lead foil should be used very carefully as it often over applied. Soft aluminum (hmmm, like skinned capacitors perhaps....) makes a very good damping material in conjunction with a viscoelastic polymer backing. I will not go into the subjective value judgments of how effective this is, but have supplied enough information for people to play with this effect. Vacuum tubes are pretty sensitive to this even in power amplifier applications. the first stage of phono preamps are critical and I have seen circuit boards mounted on rubber bands in one commercial Nuvistor based MC step up preamp. All of this stuff has been flogged to death for the last 10 years and is old news to everybody (except the people who read this forum it appears) who is a serious audio tweaker. It is amazing how much progress was made without the internet........ who knew?
http://www.percyaudio.com
http://marigoaudio.com/rone.htm
3mm White VTS Tuning Dots
http://www.positive-feedback.com/Issue1/marigovtsdots.htm
http://products3.3m.com/catalog/us/...ytapes_3_0/command_AbcPageHandler/output_html
http://www.earsc.com/CMSFrame.asp?SID=5&exturl=materials/dam.phtml
http://nadcoinc.com/FoilTapes.htm
http://products3.3m.com/catalog/us/...ytapes_3_0/command_AbcPageHandler/output_html
Attachments
maybe not......
" Peter is voicing his amp by introducing particular materials sounds due to local field effects and not due to vibrations control I expect."
I expect not.
P.S. I recycle my cans.
" Peter is voicing his amp by introducing particular materials sounds due to local field effects and not due to vibrations control I expect."
I expect not.
P.S. I recycle my cans.
SY, Don't Be So Cynical....
I have a way of modifying the taste of wines in about five or six minutes by placing the glass on a special coaster of my creation.
The result is that acid/harshness is dramatically reduced and the fruit comes out, and one year old red tastes like three or four year old red - even cask wine can be made tolerable.
This was shown in a two glass test to a wine salesman friend who knew the flavours of his wines and he was astounded.
Eric.
I have a way of modifying the taste of wines in about five or six minutes by placing the glass on a special coaster of my creation.
The result is that acid/harshness is dramatically reduced and the fruit comes out, and one year old red tastes like three or four year old red - even cask wine can be made tolerable.
This was shown in a two glass test to a wine salesman friend who knew the flavours of his wines and he was astounded.
Eric.
Re: maybe not......
Hi Phred.
I should have said "..... and not SOLELY due to vibrations control I expect."
Mechanical damping is not the only effect at work here in my experience.
Eric.
Fred Dieckmann said:
Hi Phred.
I should have said "..... and not SOLELY due to vibrations control I expect."
Mechanical damping is not the only effect at work here in my experience.
Eric.
Re: Aluminium Used To Be Called 'Congealed Electricity"
that's why they use a thin plate of copper to cool those AMD cpus: so the electronics can run faster, 🙂.
I think there may be other reasons that particular amp runs better than the use of a thin copper plate. I guess what you experienced isn't conclusive for the purpose of discussion.
mrfeedback said:
that's why they use a thin plate of copper to cool those AMD cpus: so the electronics can run faster, 🙂.
I think there may be other reasons that particular amp runs better than the use of a thin copper plate. I guess what you experienced isn't conclusive for the purpose of discussion.
Referring to the pictures above, what are the tapes for?
To put added mass on the top of caps and by doing so to increase natural frequency? Or what?
To put added mass on the top of caps and by doing so to increase natural frequency? Or what?
Re: Turn the ship upside down Unk......
Wow, $2K for a piece of cable, and god knows how much for two "dots". No wonder people are rushing into high-end audio and after all these money pouring in, we are exactly where we were 20/30/50 years ago, 🙂
At least, 3M had the sense to NOT claim their damping products will covert mechanical vibration into better electrons.
Fred Dieckmann said:
Wow, $2K for a piece of cable, and god knows how much for two "dots". No wonder people are rushing into high-end audio and after all these money pouring in, we are exactly where we were 20/30/50 years ago, 🙂
At least, 3M had the sense to NOT claim their damping products will covert mechanical vibration into better electrons.
jh6you said:Referring to the pictures above, what are the tapes for?
To put added mass on the top of caps and by doing so to increase natural frequency? Or what?
I suspect that is to fasten the caps (where I do think vibration is more likely to produce audible difference).
It looks like a piece of metal so it would also add mass to the caps and lowers their resonance frequency.
Re: Turn the ship upside down Unk......
you are perfectly correct here, Fred. And to take it one step further, the whole white world can be modeled by a set of (partial) differentiaa equations. and your resistors and transistors can be modeled by differential equations but I haven't seen any one starting to claim that they are electrically identical to each other.
Fred Dieckmann said:
you are perfectly correct here, Fred. And to take it one step further, the whole white world can be modeled by a set of (partial) differentiaa equations. and your resistors and transistors can be modeled by differential equations but I haven't seen any one starting to claim that they are electrically identical to each other.
jh6you said:Referring to the pictures above, what are the tapes for?
To put added mass on the top of caps and by doing so to increase natural frequency? Or what?
I would rather think that natural frequency would be reduced in that case. I used similar approach to damp caps in my DAC. I also think that with that method, if you overdo, you may create less then desirable effect.
My first impression after adding all those damping pads, was more silence in a sound, it's like you would move your stereo from regular listening room to an anechoic chamber. I tried to add additional pads on the top cover, but it definitely didn't work (I would say not enough sparkle in the music)😉
Attachments
Peter Daniel said:
could it be that you didn't tighten your chassis and it was vibrating at will?
I will reserve other commets.
PD, you have an amazing sense of the structural arrangement, indeed!
PD, you have an amazing sense of the structural arrangement, indeed!
millwood said:
No, it didn't vibrate at will.
jh6you said:I will reserve other commets.
PD, you have an amazing sense of the structural arrangement, indeed!
That's were my strengths in building audio really are. And I usually do my own R & D's 😉
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