I wish to take a survey to enable me to better understand what temperature parameters I will use in designing some amps. When you have time, and can provide the information being asked I believe this information will not only be useful to myself, but to everyone on diyaudio. the information should help those in need of this information to better plan and understand the effects of the different elements that affect the running temperature of the amps they wish to design or build. This is why I decided to post these questions.
I am aware the holiday season is almost upon most of you. I wish you all the best of the season. I do not need you to take the time over the holiday to measure, document , respond and comment to this request. I just finish playing with some math on output driver parameters of many of the common output devices and a few not so common output devices. While the thoughts of what I like to have sense of to better enable one to decide on practical desigh parameters are fresh in my head I decided to post this question now, before these thoughts go stale on me.
The questions are as follows:
1) Active or Passive crossover?
2) If active crossover is being used, list slopes and crossover frequencies?
3) If passive crossover being used, list slopes and crossover frequencies?
4) Indicate if active or passive crossover to subwoofer, crossover frequency range and slope, if summed or seperate woofer for each main channel?
5) Heat sink temperature when main channel amp is idle?
6) Heat sink temperature when main channel subwoofer amp is idle?
7) Heat sink temperature of main channel amp moderate SPL (for active system list woofer, mid range and tweeter)?
8) Heat sink temperature of main channel amp high SPL (for active system list woofer, mid range and tweeter)?
9) Heat sink temperature each main channel subwoofer amp moderate SPL?
10) Heat sink temperature each main channel subwoofer amp high SPL?
11) Number of output devices for one main channel amp?
12) Number of output devices for one main channel subwoofer amp?
13) Output device used for main channel amp and device case type?
14) Output device used for main channel subwoofer amp and device case type?
15) If main channel amp has one or two channels of devices on same/shared single heatsink?
16) If main channel subwoofer amp has one or two channels of devices on same/shared single heatsink?
17) If main channel amp heatsink is fan cooled?
18) If main channel subwoofer amp heatsink is fan cooled?
19) The main channel amp class/type, and if basically a "stock" diy design or extensively modified design - stock i.e. leach, aleph 5, SoZ Vx.x, A75, AV500, ESP amp type, LM3886 single, PA-100, BPA-200, et al?
20) The main channel subwoofer amp class/type, and if basically a "stock" diy design or extensively modified design - stock i.e. leach, aleph 5, SoZ Vx.x, A75, AV400, ESP amp type, LM3886 single, PA-100, BPA-200, et al?
21) The main channel amp rated watts for 8/4/2 ohms?
22) The main channel subwoofer amp rated watts for 8/4/2 ohms?
23) The main channel amp transformer VA, VRail, if amp is monoblock?
24) The main channel subwoofer amp transformer VA, VRail, if amp is monoblock?
25) Type of music generally played on system?
26) Overall SPL/1m/1W rating of main channel speakers (if active list for woofer, mid and tweeter)
27) Overall SPL/1m/1W rating of main channel subwoofer speakers ?
28) Any additional comments you feel may be revelant to temperatures measured.
29) ***** YOU HAVE BEEN WARNED!!! I TAKE NO RESPONSIBILITY IF YOU PERFORM THIS STEADY STATE SINEWAVE TEST. ***** If you feel some ambition you can measure (7), (8), (9), and (10) above with steady state sine wave, but please if you do be very very careful, as this could blow your output drivers of speakers if your system has not been designed to handle this. If you do not know if your system can handle a sinwave test then do not do the test. This is just listed shoudl someone really really know their entire system can in fact handle such a test. Most system generally cannot handle this type of steady state test. ***** YOU HAVE BEEN WARNED!!! I TAKE NO RESPONSIBILITY IF YOU PERFORM THIS STEADY STATE SINEWAVE TEST. *****
Regards,
John L. Males
Willowdale, Ontario
Canada
19 December 2004 06:53
I am aware the holiday season is almost upon most of you. I wish you all the best of the season. I do not need you to take the time over the holiday to measure, document , respond and comment to this request. I just finish playing with some math on output driver parameters of many of the common output devices and a few not so common output devices. While the thoughts of what I like to have sense of to better enable one to decide on practical desigh parameters are fresh in my head I decided to post this question now, before these thoughts go stale on me.
The questions are as follows:
1) Active or Passive crossover?
2) If active crossover is being used, list slopes and crossover frequencies?
3) If passive crossover being used, list slopes and crossover frequencies?
4) Indicate if active or passive crossover to subwoofer, crossover frequency range and slope, if summed or seperate woofer for each main channel?
5) Heat sink temperature when main channel amp is idle?
6) Heat sink temperature when main channel subwoofer amp is idle?
7) Heat sink temperature of main channel amp moderate SPL (for active system list woofer, mid range and tweeter)?
8) Heat sink temperature of main channel amp high SPL (for active system list woofer, mid range and tweeter)?
9) Heat sink temperature each main channel subwoofer amp moderate SPL?
10) Heat sink temperature each main channel subwoofer amp high SPL?
11) Number of output devices for one main channel amp?
12) Number of output devices for one main channel subwoofer amp?
13) Output device used for main channel amp and device case type?
14) Output device used for main channel subwoofer amp and device case type?
15) If main channel amp has one or two channels of devices on same/shared single heatsink?
16) If main channel subwoofer amp has one or two channels of devices on same/shared single heatsink?
17) If main channel amp heatsink is fan cooled?
18) If main channel subwoofer amp heatsink is fan cooled?
19) The main channel amp class/type, and if basically a "stock" diy design or extensively modified design - stock i.e. leach, aleph 5, SoZ Vx.x, A75, AV500, ESP amp type, LM3886 single, PA-100, BPA-200, et al?
20) The main channel subwoofer amp class/type, and if basically a "stock" diy design or extensively modified design - stock i.e. leach, aleph 5, SoZ Vx.x, A75, AV400, ESP amp type, LM3886 single, PA-100, BPA-200, et al?
21) The main channel amp rated watts for 8/4/2 ohms?
22) The main channel subwoofer amp rated watts for 8/4/2 ohms?
23) The main channel amp transformer VA, VRail, if amp is monoblock?
24) The main channel subwoofer amp transformer VA, VRail, if amp is monoblock?
25) Type of music generally played on system?
26) Overall SPL/1m/1W rating of main channel speakers (if active list for woofer, mid and tweeter)
27) Overall SPL/1m/1W rating of main channel subwoofer speakers ?
28) Any additional comments you feel may be revelant to temperatures measured.
29) ***** YOU HAVE BEEN WARNED!!! I TAKE NO RESPONSIBILITY IF YOU PERFORM THIS STEADY STATE SINEWAVE TEST. ***** If you feel some ambition you can measure (7), (8), (9), and (10) above with steady state sine wave, but please if you do be very very careful, as this could blow your output drivers of speakers if your system has not been designed to handle this. If you do not know if your system can handle a sinwave test then do not do the test. This is just listed shoudl someone really really know their entire system can in fact handle such a test. Most system generally cannot handle this type of steady state test. ***** YOU HAVE BEEN WARNED!!! I TAKE NO RESPONSIBILITY IF YOU PERFORM THIS STEADY STATE SINEWAVE TEST. *****
Regards,
John L. Males
Willowdale, Ontario
Canada
19 December 2004 06:53
Hi John,
Wow, a ton of questions!
Try to post the speaker based questions in that forum. You wil get a better response.
Heatsink temperature is heatsink temerature. Why not just ask what most are running, and the design? I think idle and high level temps may give you what you want.
I have dummy loads and several amps. Most of us may not be so lucky. I will take some measurements for you.
-Chris
Wow, a ton of questions!
Try to post the speaker based questions in that forum. You wil get a better response.
Heatsink temperature is heatsink temerature. Why not just ask what most are running, and the design? I think idle and high level temps may give you what you want.
I have dummy loads and several amps. Most of us may not be so lucky. I will take some measurements for you.
-Chris
1) Active or Passive crossover?
active
2) If active crossover is being used, list slopes and crossover frequencies?
110Hz, 340Hz, 1.1k, 4.1k all 4th order LR
3) If passive crossover being used, list slopes and crossover frequencies?
none
4) Indicate if active or passive crossover to subwoofer, crossover frequency range and slope, if summed or seperate woofer for each main channel?
active to sub
5) Heat sink temperature when main channel amp is idle?
~10C above ambient
6) Heat sink temperature when main channel subwoofer amp is idle?
~15C above ambient
7) Heat sink temperature of main channel amp moderate SPL (for active system list woofer, mid range and tweeter)?
~15C above ambient
8) Heat sink temperature of main channel amp high SPL (for active system list woofer, mid range and tweeter)?
~25C above ambient
9) Heat sink temperature each main channel subwoofer amp moderate SPL?
~20C above ambient
10) Heat sink temperature each main channel subwoofer amp high SPL?
~25-30C above ambient
11) Number of output devices for one main channel amp?
1 pair for each P3A (four in all) 2 pairs for each 250W amp (midbasses, two)
12) Number of output devices for one main channel subwoofer amp?
4 pairs /ch for n channel amp for subs.
13) Output device used for main channel amp and device case type?
MJ15003/4 TO-3
14) Output device used for main channel subwoofer amp and device case type?
IRFP250 TO-247
15) If main channel amp has one or two channels of devices on same/shared single heatsink?
all amps on individual heatsinks
16) If main channel subwoofer amp has one or two channels of devices on same/shared single heatsink?
same as above
17) If main channel amp heatsink is fan cooled?
all my amps are fan cooled, thermally controlled.
18) If main channel subwoofer amp heatsink is fan cooled?
same as above
19) The main channel amp class/type, and if basically a "stock" diy design or extensively modified design - stock i.e. leach, aleph 5, SoZ Vx.x, A75, AV500, ESP amp type, LM3886 single, PA-100, BPA-200, et al?
tweets and mids use P3A's @ +/-35V
midbasses use modified class b amp kit @+/-50V
20) The main channel subwoofer amp class/type, and if basically a "stock" diy design or extensively modified design - stock i.e. leach, aleph 5, SoZ Vx.x, A75, AV400, ESP amp type, LM3886 single, PA-100, BPA-200, et al?
two 12" JBL's powered by two holton N channel amps @+/-70V
21) The main channel amp rated watts for 8/4/2 ohms?
100Wx4 into 4 ohms + 250Wx2 into 4 ohms
22) The main channel subwoofer amp rated watts for 8/4/2 ohms?
400Wx2 into 4 ohms
23) The main channel amp transformer VA, VRail, if amp is monoblock?
+/-35V, two channels per tranny in all amps.
24) The main channel subwoofer amp transformer VA, VRail, if amp is monoblock?
same as above
25) Type of music generally played on system?
almost anything under the sun
26) Overall SPL/1m/1W rating of main channel speakers (if active list for woofer, mid and tweeter)
~90db/1w/1m
27) Overall SPL/1m/1W rating of main channel subwoofer speakers ?
~93db/1w/1m
28) Any additional comments you feel may be revelant to temperatures measured.
measured temp's are with music signals. I don't think my amps can handle continuous sine testing. but I have tried playing bass CD's for car stereos and the amps handled it well.
active
2) If active crossover is being used, list slopes and crossover frequencies?
110Hz, 340Hz, 1.1k, 4.1k all 4th order LR
3) If passive crossover being used, list slopes and crossover frequencies?
none
4) Indicate if active or passive crossover to subwoofer, crossover frequency range and slope, if summed or seperate woofer for each main channel?
active to sub
5) Heat sink temperature when main channel amp is idle?
~10C above ambient
6) Heat sink temperature when main channel subwoofer amp is idle?
~15C above ambient
7) Heat sink temperature of main channel amp moderate SPL (for active system list woofer, mid range and tweeter)?
~15C above ambient
8) Heat sink temperature of main channel amp high SPL (for active system list woofer, mid range and tweeter)?
~25C above ambient
9) Heat sink temperature each main channel subwoofer amp moderate SPL?
~20C above ambient
10) Heat sink temperature each main channel subwoofer amp high SPL?
~25-30C above ambient
11) Number of output devices for one main channel amp?
1 pair for each P3A (four in all) 2 pairs for each 250W amp (midbasses, two)
12) Number of output devices for one main channel subwoofer amp?
4 pairs /ch for n channel amp for subs.
13) Output device used for main channel amp and device case type?
MJ15003/4 TO-3
14) Output device used for main channel subwoofer amp and device case type?
IRFP250 TO-247
15) If main channel amp has one or two channels of devices on same/shared single heatsink?
all amps on individual heatsinks
16) If main channel subwoofer amp has one or two channels of devices on same/shared single heatsink?
same as above
17) If main channel amp heatsink is fan cooled?
all my amps are fan cooled, thermally controlled.
18) If main channel subwoofer amp heatsink is fan cooled?
same as above
19) The main channel amp class/type, and if basically a "stock" diy design or extensively modified design - stock i.e. leach, aleph 5, SoZ Vx.x, A75, AV500, ESP amp type, LM3886 single, PA-100, BPA-200, et al?
tweets and mids use P3A's @ +/-35V
midbasses use modified class b amp kit @+/-50V
20) The main channel subwoofer amp class/type, and if basically a "stock" diy design or extensively modified design - stock i.e. leach, aleph 5, SoZ Vx.x, A75, AV400, ESP amp type, LM3886 single, PA-100, BPA-200, et al?
two 12" JBL's powered by two holton N channel amps @+/-70V
21) The main channel amp rated watts for 8/4/2 ohms?
100Wx4 into 4 ohms + 250Wx2 into 4 ohms
22) The main channel subwoofer amp rated watts for 8/4/2 ohms?
400Wx2 into 4 ohms
23) The main channel amp transformer VA, VRail, if amp is monoblock?
+/-35V, two channels per tranny in all amps.
24) The main channel subwoofer amp transformer VA, VRail, if amp is monoblock?
same as above
25) Type of music generally played on system?
almost anything under the sun
26) Overall SPL/1m/1W rating of main channel speakers (if active list for woofer, mid and tweeter)
~90db/1w/1m
27) Overall SPL/1m/1W rating of main channel subwoofer speakers ?
~93db/1w/1m
28) Any additional comments you feel may be revelant to temperatures measured.
measured temp's are with music signals. I don't think my amps can handle continuous sine testing. but I have tried playing bass CD's for car stereos and the amps handled it well.
Re[02]: Wow, a ton of questions!
Hi Chris,
Chris, if your dummy load is purely resistive I think it would not be worth your time to run the tests. I rather have real life load data with speakers. Any responses with active crossovers with be as resistive a load as one will likely have in real world with woofers/subwoofers being the least likely to being purely resistive in active system.
The list of questions did start very small, but it was pointless to just ask temperature without properly knowing certain parameters to be able to quantify. Some variables are if two amps both running about 60C temp but one is using single output driver pair and another is using 4 pairs is very important, or amp is Class A or AB makes big difference to what one can take from the temperature data. As this is a diy audience, idle was asked because many may tweek the bias higher then others. These are only some of the reasons behind being better able to quanify the core questions I have about temperature.
This is why the list of questions is "long", so the data can be useful, not just for me, but for anyone else that may find such data helpful to their own amp design. There are in fact a number of factors that impact how hard the devices have to work. It seems wiser to better to quantify the information and try to ask for it only once.
I also feel indirectly the questions I pose provide a list for those designing an amp to consider in order to determine their SOA output device(s) needs. So, even without any answers this set of questions provides a checklist of factors to consider that will translate to the thermal demands the output device(s) will experience.
Based on alot of math I have done with various output drivers it became very apparent how operating temperature of output devices in SOA can easily be under estimated and the various factors in design one considers and uses to run in the SOA. My questions are based on reading various threads. Some have used very agressive safety factors to avoid thermal issues or device failure, some are also very agressive how far they believe a device can be pushed. The output devices have many ratings that can combine to fall short or have taken so much safety factor it that it may reduce the sonic quality of the amp designed.
As this survey is primarily about output driver temperature, of which speakers being used (active or passive, etc) are a definite factor in the load the amp sees, I placed the survey questions here. I am trying to evaulate and determine how many output drivers I need. What I found hard to know in advance was what the real life operating temeprature would be. I found through the math that even a difference of 10C had quite a remarkable difference in device power handling ability and lifespan. I felt I may not be the only one considering this important question based on many prior discussions in many threads asking various questions realted to thermal aspects of amp design. There were those that felt they knew what would be real life and found real life operating temperatures very different to what they had assumed. Others based thermal design with assumptions on less qualified questions of others temperature data with result generally much hotter results than had planned even when they choose to design to design to much higher operating temperature than they ever expected.
Opps, now I have already realize I should of asked how the devices were thermally insulated. See one more question I failed to ask. Oh well time to update the questions.
Regards,
John L. Males
Willowdale, Ontario
Canada
19 December 2004 18:22
anatech said:
Hi Chris,
Chris, if your dummy load is purely resistive I think it would not be worth your time to run the tests. I rather have real life load data with speakers. Any responses with active crossovers with be as resistive a load as one will likely have in real world with woofers/subwoofers being the least likely to being purely resistive in active system.
The list of questions did start very small, but it was pointless to just ask temperature without properly knowing certain parameters to be able to quantify. Some variables are if two amps both running about 60C temp but one is using single output driver pair and another is using 4 pairs is very important, or amp is Class A or AB makes big difference to what one can take from the temperature data. As this is a diy audience, idle was asked because many may tweek the bias higher then others. These are only some of the reasons behind being better able to quanify the core questions I have about temperature.
This is why the list of questions is "long", so the data can be useful, not just for me, but for anyone else that may find such data helpful to their own amp design. There are in fact a number of factors that impact how hard the devices have to work. It seems wiser to better to quantify the information and try to ask for it only once.
I also feel indirectly the questions I pose provide a list for those designing an amp to consider in order to determine their SOA output device(s) needs. So, even without any answers this set of questions provides a checklist of factors to consider that will translate to the thermal demands the output device(s) will experience.
Based on alot of math I have done with various output drivers it became very apparent how operating temperature of output devices in SOA can easily be under estimated and the various factors in design one considers and uses to run in the SOA. My questions are based on reading various threads. Some have used very agressive safety factors to avoid thermal issues or device failure, some are also very agressive how far they believe a device can be pushed. The output devices have many ratings that can combine to fall short or have taken so much safety factor it that it may reduce the sonic quality of the amp designed.
As this survey is primarily about output driver temperature, of which speakers being used (active or passive, etc) are a definite factor in the load the amp sees, I placed the survey questions here. I am trying to evaulate and determine how many output drivers I need. What I found hard to know in advance was what the real life operating temeprature would be. I found through the math that even a difference of 10C had quite a remarkable difference in device power handling ability and lifespan. I felt I may not be the only one considering this important question based on many prior discussions in many threads asking various questions realted to thermal aspects of amp design. There were those that felt they knew what would be real life and found real life operating temperatures very different to what they had assumed. Others based thermal design with assumptions on less qualified questions of others temperature data with result generally much hotter results than had planned even when they choose to design to design to much higher operating temperature than they ever expected.
Opps, now I have already realize I should of asked how the devices were thermally insulated. See one more question I failed to ask. Oh well time to update the questions.
Regards,
John L. Males
Willowdale, Ontario
Canada
19 December 2004 18:22
Hi John,
No problem with that. Basically, you want to know the operating conditions and temperature. Some amplifiers do not use drivers (Counterpoint SA-100 family). Others may mount the drivers to the heatsink which is what you initially assumed I think. This is what I'd tend to do in a new design. (I'm working on one now).
As far as dummy loads are concerned, they are valid as they are the only constant we have. A phase angle can be introduced, just pick a standard load. I use the 250W Dale resistors mounted on heatsinks. From time to time I throw 0.22uF across them. I also have 4 ohm 225W resistors.
You may want to ask about ventillation space as that will affect the inside case ambient temp. This is also very important to know.
Anyway, I will take some measurements for you. I normally do this on amp test with a digital lab thermometer. I fully agree with you on the use of this data. Also the difference that 10C will make. Good project!
-Chris
No problem with that. Basically, you want to know the operating conditions and temperature. Some amplifiers do not use drivers (Counterpoint SA-100 family). Others may mount the drivers to the heatsink which is what you initially assumed I think. This is what I'd tend to do in a new design. (I'm working on one now).
As far as dummy loads are concerned, they are valid as they are the only constant we have. A phase angle can be introduced, just pick a standard load. I use the 250W Dale resistors mounted on heatsinks. From time to time I throw 0.22uF across them. I also have 4 ohm 225W resistors.
You may want to ask about ventillation space as that will affect the inside case ambient temp. This is also very important to know.
Anyway, I will take some measurements for you. I normally do this on amp test with a digital lab thermometer. I fully agree with you on the use of this data. Also the difference that 10C will make. Good project!
-Chris
Good Points
Hi Chris,
I hit the enter button when I meant to hit the shift button!!! Err. so the first instance of this reply was just your message in quotes with no comments from me. lol lol I suppose that would suit some people fine
Yes, I want to know about those amps with output drivers. If the amp like the CounterPoint SA-100 does not, then it is implied it is not of interest to these questions.
I have not stated if drivers are mounted to a heatsink, use case for heatsink, et al. I used "heatsink" to mean what the output device(s) are thermally connected to to reduce their operating temperature. All that is important is whatever is being used to draw heat from the output device(s) temperature. I leave it up to the person choosing to respond to indicate if there a if case or something else is used in lieu of "heatsink" in any additional comments question I have.
If you feel a dummy resistor load test and/or dummy resistive load test with inductor or capacitor is useful, feel free to post those. My suggestion is to make one post of the data for a combination used for a test to keep things clear. So if one does a pure resistive non-inductive resistor, a resistor/capacitor, a resistor/inductor/capacitor set of tests, then I would suggest three different postings. If you do same test with different values such as a resistive test of 8 and then 4 ohms I would suggest post each one seperately. This just avoids confusion.
Your point about ventillation space is interesting, but out of scope for what data is being asked for. Just like I have not asked how much heat sink is being used. Fan cooling was asked as very different to convection cooling in terms of how much implied heatsinking was designed for in terms of temperature/watt of cooling. One could then start to asked if open cage, if equipment is around amp blocking air flow, etc. Those are not the foundation of the questions here. The foundation is what is the output device seeing as a temperature, not how do I make the output decice(s) operate at a cooler temperature.
Regards,
John L. Males
Willowdale, Ontario
Canada
19 December 2004 19:59 (opps, actual reply to the message, not just reposte message as quoted)
19 December 2004 20:10 (Minor type corrections)
anatech said:
Hi Chris,
I hit the enter button when I meant to hit the shift button!!! Err. so the first instance of this reply was just your message in quotes with no comments from me. lol lol I suppose that would suit some people fine
Yes, I want to know about those amps with output drivers. If the amp like the CounterPoint SA-100 does not, then it is implied it is not of interest to these questions.
I have not stated if drivers are mounted to a heatsink, use case for heatsink, et al. I used "heatsink" to mean what the output device(s) are thermally connected to to reduce their operating temperature. All that is important is whatever is being used to draw heat from the output device(s) temperature. I leave it up to the person choosing to respond to indicate if there a if case or something else is used in lieu of "heatsink" in any additional comments question I have.
If you feel a dummy resistor load test and/or dummy resistive load test with inductor or capacitor is useful, feel free to post those. My suggestion is to make one post of the data for a combination used for a test to keep things clear. So if one does a pure resistive non-inductive resistor, a resistor/capacitor, a resistor/inductor/capacitor set of tests, then I would suggest three different postings. If you do same test with different values such as a resistive test of 8 and then 4 ohms I would suggest post each one seperately. This just avoids confusion.
Your point about ventillation space is interesting, but out of scope for what data is being asked for. Just like I have not asked how much heat sink is being used. Fan cooling was asked as very different to convection cooling in terms of how much implied heatsinking was designed for in terms of temperature/watt of cooling. One could then start to asked if open cage, if equipment is around amp blocking air flow, etc. Those are not the foundation of the questions here. The foundation is what is the output device seeing as a temperature, not how do I make the output decice(s) operate at a cooler temperature.
Regards,
John L. Males
Willowdale, Ontario
Canada
19 December 2004 19:59 (opps, actual reply to the message, not just reposte message as quoted)
19 December 2004 20:10 (Minor type corrections)
Hi John,
Understood. But the ventillation does affect the circuit operation. Case in point. Revox B242 amps. Forced air cooling with 2" above the unit in the Revox rack - Boom. Marantz 2500, forced air. Just had a customer with 4" in the back. Took a while but - Boom. In the case of the Revox, O/P's were fine but the other circuits were overheated. I'm not trying to pick on extremes. I am just trying to point out that in my experience, ambient case teperature is very important. Lack of ambient may invalidate some of your figures.
I am with you on this by the way, don't take any of this as critisism.
-Chris
Understood. But the ventillation does affect the circuit operation. Case in point. Revox B242 amps. Forced air cooling with 2" above the unit in the Revox rack - Boom. Marantz 2500, forced air. Just had a customer with 4" in the back. Took a while but - Boom. In the case of the Revox, O/P's were fine but the other circuits were overheated. I'm not trying to pick on extremes. I am just trying to point out that in my experience, ambient case teperature is very important. Lack of ambient may invalidate some of your figures.
I am with you on this by the way, don't take any of this as critisism.
-Chris
Re[02]: Survey - Actual Amp Temperatures
I cannot edit the inital posting so to refine or add additional questions to this thread I am replying to my own first post so people do not have to dig through the thread to "accumulate" the questions. I will keep the numbering the same for the question being asked so the numbers to answers do not change throughout this to avoid adding complicated confusion to the data. This message post will be where to find the "reference" for the questions being asked from now on.
I wish to take a survey to enable me to better understand what temperature parameters I will use in designing some amps. When you have time, and can provide the information being asked I believe this information will not only be useful to myself, but to everyone on diyaudio. the information should help those in need of this information to better plan and understand the effects of the different elements that affect the running temperature of the amps they wish to design or build. This is why I decided to post these questions.
I am aware the holiday season is almost upon most of you. I wish you all the best of the season. I do not need you to take the time over the holiday to measure, document , respond and comment to this request. I just finish playing with some math on output driver parameters of many of the common output devices and a few not so common output devices. While the thoughts of what I like to have sense of to better enable one to decide on practical desigh parameters are fresh in my head I decided to post this question now, before these thoughts go stale on me.
Please state temperatures in absolute, not above abient. Somone could be in thr tropics with no air conditioning, another in Alaska, someone could have air conitioning in summer, someone else may not have air conditioning.
If you have different amps, condition combinations such as type of speaker, load, or different temperature due to time of year or air conditioning please post each seperate. Conditions such as these will be helpful for those needing to compare worse case time of year or environment conditions and be able to have some sense of how much this may impact the temperature the output device is operating at.
If you feel a dummy resistor load test and/or dummy resistive load test with inductor or capacitor is useful, feel free to post those. My suggestion is to make one post of the data for a combination used for a test to keep things clear. So if one does a pure resistive non-inductive resistor, a resistor/capacitor, a resistor/inductor/capacitor set of tests, then I would suggest three different postings. If you do same test with different values such as a resistive test of 8 and then 4 ohms I would suggest post each one seperately. This just avoids confusion.
The purpose and reason for questions in this thread is about design, not if someone blocks ventillation to the heatsink cooling, not if devices were properly matched to share load of paralled output devices, etc.
The questions are as follows:
1) Active or Passive crossover?
2) If active crossover is being used, list slopes and crossover frequencies?
3) If passive crossover being used, list slopes and crossover frequencies?
4) Indicate if active or passive crossover to subwoofer, crossover frequency range and slope, if summed or seperate woofer for each main channel?
5) Heat sink temperature when main channel amp is idle?
6) Heat sink temperature when main channel subwoofer amp is idle?
7) Heat sink temperature of main channel amp moderate SPL (for active system list woofer, mid range and tweeter)?
8) Heat sink temperature of main channel amp high SPL (for active system list woofer, mid range and tweeter)?
9) Heat sink temperature each main channel subwoofer amp moderate SPL?
10) Heat sink temperature each main channel subwoofer amp high SPL?
11) Number of output devices for one main channel amp?
12) Number of output devices for one main channel subwoofer amp?
13) Output device used for main channel amp and device case type?
14) Output device used for main channel subwoofer amp and device case type?
15) If main channel amp has one or two channels of devices on same/shared single heatsink?
16) If main channel subwoofer amp has one or two channels of devices on same/shared single heatsink?
17) If main channel amp heatsink is fan cooled?
18) If main channel subwoofer amp heatsink is fan cooled?
19) The main channel amp class/type, and if basically a "stock" diy design or extensively modified design - stock i.e. leach, aleph 5, SoZ Vx.x, A75, AV500, ESP amp type, LM3886 single, PA-100, BPA-200, et al?
20) The main channel subwoofer amp class/type, and if basically a "stock" diy design or extensively modified design - stock i.e. leach, aleph 5, SoZ Vx.x, A75, AV400, ESP amp type, LM3886 single, PA-100, BPA-200, et al?
21) The main channel amp rated watts for 8/4/2 ohms?
22) The main channel subwoofer amp rated watts for 8/4/2 ohms?
23) The main channel amp transformer VA, VRail, if amp is monoblock?
24) The main channel subwoofer amp transformer VA, VRail, if amp is monoblock?
25) Type of music generally played on system?
26) Overall SPL/1m/1W rating of main channel speakers (if active list for woofer, mid and tweeter)
27) Overall SPL/1m/1W rating of main channel subwoofer speakers ?
28) Any additional comments you feel may be revelant to temperatures measured.
29) ***** YOU HAVE BEEN WARNED!!! I TAKE NO RESPONSIBILITY IF YOU PERFORM THIS STEADY STATE SINEWAVE TEST. ***** If you feel some ambition you can measure (7), (8), (9), and (10) above with steady state sine wave, but please if you do be very very careful, as this could blow your output drivers of speakers if your system has not been designed to handle this. If you do not know if your system can handle a sinwave test then do not do the test. This is just listed shoudl someone really really know their entire system can in fact handle such a test. Most system generally cannot handle this type of steady state test. ***** YOU HAVE BEEN WARNED!!! I TAKE NO RESPONSIBILITY IF YOU PERFORM THIS STEADY STATE SINEWAVE TEST. *****
30) How are the output devices thermally insulated from the heatsink or if not thermally insulated at all please also state.
Regards,
John L. Males
Willowdale, Ontario
Canada
19 December 2004 06:53
19 Devember 2004 20:33 ( Asked for absolute temperature not relative to ambient, Added question 30, added points of guidance for using "dummy" load type tests, one set of resutls for each different load type/value/time of year/environment test, defining out of scope issues such as blocked ventillention, improperly matched paralled output devices, etc)
I cannot edit the inital posting so to refine or add additional questions to this thread I am replying to my own first post so people do not have to dig through the thread to "accumulate" the questions. I will keep the numbering the same for the question being asked so the numbers to answers do not change throughout this to avoid adding complicated confusion to the data. This message post will be where to find the "reference" for the questions being asked from now on.
I wish to take a survey to enable me to better understand what temperature parameters I will use in designing some amps. When you have time, and can provide the information being asked I believe this information will not only be useful to myself, but to everyone on diyaudio. the information should help those in need of this information to better plan and understand the effects of the different elements that affect the running temperature of the amps they wish to design or build. This is why I decided to post these questions.
I am aware the holiday season is almost upon most of you. I wish you all the best of the season. I do not need you to take the time over the holiday to measure, document , respond and comment to this request. I just finish playing with some math on output driver parameters of many of the common output devices and a few not so common output devices. While the thoughts of what I like to have sense of to better enable one to decide on practical desigh parameters are fresh in my head I decided to post this question now, before these thoughts go stale on me.
Please state temperatures in absolute, not above abient. Somone could be in thr tropics with no air conditioning, another in Alaska, someone could have air conitioning in summer, someone else may not have air conditioning.
If you have different amps, condition combinations such as type of speaker, load, or different temperature due to time of year or air conditioning please post each seperate. Conditions such as these will be helpful for those needing to compare worse case time of year or environment conditions and be able to have some sense of how much this may impact the temperature the output device is operating at.
If you feel a dummy resistor load test and/or dummy resistive load test with inductor or capacitor is useful, feel free to post those. My suggestion is to make one post of the data for a combination used for a test to keep things clear. So if one does a pure resistive non-inductive resistor, a resistor/capacitor, a resistor/inductor/capacitor set of tests, then I would suggest three different postings. If you do same test with different values such as a resistive test of 8 and then 4 ohms I would suggest post each one seperately. This just avoids confusion.
The purpose and reason for questions in this thread is about design, not if someone blocks ventillation to the heatsink cooling, not if devices were properly matched to share load of paralled output devices, etc.
The questions are as follows:
1) Active or Passive crossover?
2) If active crossover is being used, list slopes and crossover frequencies?
3) If passive crossover being used, list slopes and crossover frequencies?
4) Indicate if active or passive crossover to subwoofer, crossover frequency range and slope, if summed or seperate woofer for each main channel?
5) Heat sink temperature when main channel amp is idle?
6) Heat sink temperature when main channel subwoofer amp is idle?
7) Heat sink temperature of main channel amp moderate SPL (for active system list woofer, mid range and tweeter)?
8) Heat sink temperature of main channel amp high SPL (for active system list woofer, mid range and tweeter)?
9) Heat sink temperature each main channel subwoofer amp moderate SPL?
10) Heat sink temperature each main channel subwoofer amp high SPL?
11) Number of output devices for one main channel amp?
12) Number of output devices for one main channel subwoofer amp?
13) Output device used for main channel amp and device case type?
14) Output device used for main channel subwoofer amp and device case type?
15) If main channel amp has one or two channels of devices on same/shared single heatsink?
16) If main channel subwoofer amp has one or two channels of devices on same/shared single heatsink?
17) If main channel amp heatsink is fan cooled?
18) If main channel subwoofer amp heatsink is fan cooled?
19) The main channel amp class/type, and if basically a "stock" diy design or extensively modified design - stock i.e. leach, aleph 5, SoZ Vx.x, A75, AV500, ESP amp type, LM3886 single, PA-100, BPA-200, et al?
20) The main channel subwoofer amp class/type, and if basically a "stock" diy design or extensively modified design - stock i.e. leach, aleph 5, SoZ Vx.x, A75, AV400, ESP amp type, LM3886 single, PA-100, BPA-200, et al?
21) The main channel amp rated watts for 8/4/2 ohms?
22) The main channel subwoofer amp rated watts for 8/4/2 ohms?
23) The main channel amp transformer VA, VRail, if amp is monoblock?
24) The main channel subwoofer amp transformer VA, VRail, if amp is monoblock?
25) Type of music generally played on system?
26) Overall SPL/1m/1W rating of main channel speakers (if active list for woofer, mid and tweeter)
27) Overall SPL/1m/1W rating of main channel subwoofer speakers ?
28) Any additional comments you feel may be revelant to temperatures measured.
29) ***** YOU HAVE BEEN WARNED!!! I TAKE NO RESPONSIBILITY IF YOU PERFORM THIS STEADY STATE SINEWAVE TEST. ***** If you feel some ambition you can measure (7), (8), (9), and (10) above with steady state sine wave, but please if you do be very very careful, as this could blow your output drivers of speakers if your system has not been designed to handle this. If you do not know if your system can handle a sinwave test then do not do the test. This is just listed shoudl someone really really know their entire system can in fact handle such a test. Most system generally cannot handle this type of steady state test. ***** YOU HAVE BEEN WARNED!!! I TAKE NO RESPONSIBILITY IF YOU PERFORM THIS STEADY STATE SINEWAVE TEST. *****
30) How are the output devices thermally insulated from the heatsink or if not thermally insulated at all please also state.
Regards,
John L. Males
Willowdale, Ontario
Canada
19 December 2004 06:53
19 Devember 2004 20:33 ( Asked for absolute temperature not relative to ambient, Added question 30, added points of guidance for using "dummy" load type tests, one set of resutls for each different load type/value/time of year/environment test, defining out of scope issues such as blocked ventillention, improperly matched paralled output devices, etc)
Re[04]: ventillation
Chris,
Understand your point about ventillation. I have defined the ventillation as out of scope as if the "user" had used the amp as it was designed and followed the need for enough space about the amp them the amp or internal circuits woudl not have blown. I have also limited this thread to the output devices, not output drivers, voltage ratings of capacitors, resistors, et al as again this in not the intent of the thread. It is too easy for people to loose sight of the conditions or what is in scope for matter at hand. I just like the data in thread to be about the data as much as possible and not diversion on heatsink calculations, SOA calculations, driver heatsink/SOA, driver voltage rating vs rail voltage, et al. Those are all valid design questions and considerations, but not the terms of the thread. I like the thread to be about the data, not wading through many posts to find data.
As for ventillation point you raise, no I am not offended at all by you raising the point. This to me is mostly user error, ignoring or simply not reading the amps manual. Sorry, but that is not design question unless the manual requested 20 feet of space around the amp! Your point about ventillation raises how easy it is for a topic to branch off in different directions. So my reply is not just to you Chris, but also to those reading this thread so they understand the importance to keep to the data so the data can be easly found and made use of.
Yes a 20 feet space requirement about an amp is insane as a design requirement, but why I point it out as an example. If at 20 feet open space about an amp means it performs fine and as expected, so be it. That was the design. If someone had an amp with such a design requirement and wanted to answer the questions of this thread, that would be just fine as long as the additional comments listed this unusual design requirement for 20 feet of space around the amp I have no problem with such data being provided, and expect nobody to rant about posting such data as long as it was real data of real design.
If I sound like I am offended Chris, I am not. I come from a Software QA Engineering backgound, so I know all to well how well to define or determine what is or not in scope. I know how most do not understnd this very well, and how ofen I can be out of scope as well branching off on several tangents of topic to "related" items. ) So I know all to well how I can get out of scope!
Regards,
John L. Males
Willowdale, Ontario
Canada
19 December 2004 20:57
anatech said:
Chris,
Understand your point about ventillation. I have defined the ventillation as out of scope as if the "user" had used the amp as it was designed and followed the need for enough space about the amp them the amp or internal circuits woudl not have blown. I have also limited this thread to the output devices, not output drivers, voltage ratings of capacitors, resistors, et al as again this in not the intent of the thread. It is too easy for people to loose sight of the conditions or what is in scope for matter at hand. I just like the data in thread to be about the data as much as possible and not diversion on heatsink calculations, SOA calculations, driver heatsink/SOA, driver voltage rating vs rail voltage, et al. Those are all valid design questions and considerations, but not the terms of the thread. I like the thread to be about the data, not wading through many posts to find data.
As for ventillation point you raise, no I am not offended at all by you raising the point. This to me is mostly user error, ignoring or simply not reading the amps manual. Sorry, but that is not design question unless the manual requested 20 feet of space around the amp! Your point about ventillation raises how easy it is for a topic to branch off in different directions. So my reply is not just to you Chris, but also to those reading this thread so they understand the importance to keep to the data so the data can be easly found and made use of.
Yes a 20 feet space requirement about an amp is insane as a design requirement, but why I point it out as an example. If at 20 feet open space about an amp means it performs fine and as expected, so be it. That was the design. If someone had an amp with such a design requirement and wanted to answer the questions of this thread, that would be just fine as long as the additional comments listed this unusual design requirement for 20 feet of space around the amp I have no problem with such data being provided, and expect nobody to rant about posting such data as long as it was real data of real design.
If I sound like I am offended Chris, I am not. I come from a Software QA Engineering backgound, so I know all to well how well to define or determine what is or not in scope. I know how most do not understnd this very well, and how ofen I can be out of scope as well branching off on several tangents of topic to "related" items.
) So I know all to well how I can get out of scope! Regards,
John L. Males
Willowdale, Ontario
Canada
19 December 2004 20:57
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