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Post by garbulky on Dec 1, 2017 18:10:41 GMT -5
So using 30% of the amps rated power for an hour is considered crazy? Have you guys seen the transformers movie?!  Since the "preconditioning" is done with "continuous" watts, and 100 watts driving a speaker with a decent sensitivity of 90dB would yield ~110 dBs, yeah, I kinda do...  Pshhhh....this is me when I do some quiet listening  |
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Post by doc1963 on Dec 1, 2017 18:23:17 GMT -5
Since the "preconditioning" is done with "continuous" watts, and 100 watts driving a speaker with a decent sensitivity of 90dB would yield ~110 dBs, yeah, I kinda do... Pshhhh....this is me when I do some quiet listening LOL... can’t say that I’m not guilty of this too... |
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Post by AudioHTIT on Dec 1, 2017 18:46:25 GMT -5
... The gen 3 is just a curiosity for me at this point. I'll wait till either Emotiva gets its head back on straight regarding its switching PS. Or if they transition to switching, then I'll just wait for the replacement company that is sure to come to occupy the niche of cheap heavy iron that Emotiva seems keen on leaving open to the competition. ... The Gen 3 for me however puts Emotiva back in the running for my next amp. Due to my feeling that the technology has matured more than enough for high quality audio, and because it’s efficiency is so much better, I had pretty much decided my next HT amp would be Class D. After seeing geebo’s idle measurements on the XPA-2 G3, and hearing Keith’s anecdotal account of the XPA-7 G3 idle rating, I saw that they compare favorably to Class D amps in efficiency. If the technology can deliver an amp that sounds good, doesn’t use more power than is needed to produce sufficient output, and doesn’t generate excess heat, then that’s what I want. I recognize from Gary Cook ’s efficiency thread, and my measurements thread, that I’m in a minority desiring an efficient amp that generates less heat, but that’s never bothered me. I’d really love it if someone would post idle power on an XPA G3 with 7, 9, or 11 channels, it seems like they all might be pretty close. The Post Your Measurements ThreadSo, they might lose you, but they might keep me, different strokes ... |
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Post by Casey Leedom on Dec 1, 2017 18:47:28 GMT -5
Huh. Thanks for the background KeithL, I stand ... er, sit corrected ... Casey |
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Post by mgbpuff on Dec 1, 2017 20:14:33 GMT -5
The 1/3 power test is standard in the amp testing world. If your amp doesn’t pass, then if you don’t want to fix it, just deny the validity of the test. Next, Bruno Putzey - this guy developed his class D amp by the Edison method, over many years which is a dogged try, try, and then try again approach. His designs only succeed if every detail of circuit board design is just so. Any relocation or spacing change of any given component can upset the apple cart. Locating wiring to his boards must be just so, and the power supplies must be carefully located. This is a high risk and high cost way to design and that is why his and other class D amps are sold in pre- manufactured modules. This is not likely to be a viable path for Emotiva. Then there's Nelson Pass who only does analog and hates Class D. I have no objection to negative feedback, in fact feedback is necessary in solid state design due to the increased non linearity of solid state devices compared to tubes.
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Post by geebo on Dec 1, 2017 20:33:25 GMT -5
The 1/3 power test is standard in the amp testing world. If your amp doesn’t pass, then if you don’t want to fix it, just deny the validity of the test. Next, Bruno Putzey- this guy developed his class D amp by the Edison method, over many years which is a dogged try, try, and then try again approach. His designs only succeed if every detail of circuit board design is just so. Any relocation or spacing change of any given component can upset the apple cart. Locating wiring to his boards must be just so, and tha power supplies must be carefully located. This is a high risk and high cost way to design and that is why his and other class D amps are sold in pre- manufactured modules. This is not likely to be a viable path for Emotiva. Okay, if 1/3 power is the standard then why didn't they test that 500 watt monoblock Dan spoke of at 166 watts instead of 100 watts or 20% of rated power? I guess we'll never know how it would have fared at 33%. That 13% increase in power output relates to something like 30% more voltage output at the speaker terminals. |
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Post by Casey Leedom on Dec 1, 2017 20:35:09 GMT -5
... Next, Bruno Putzey - this guy developed his class D amp by the Edison method, over many years which is a dogged try, try, and then try again approach. His designs only succeed if every detail of circuit board design is just so. Any relocation or spacing change of any given component can upset the apple cart. Locating wiring to his boards must be just so, and the power supplies must be carefully located. This is a high risk and high cost way to design and that is why his and other class D amps are sold in pre- manufactured modules. This is not likely to be a viable path for Emotiva. Then there's Nelson Pass who only does analog and hates Class D. I have no objection to negative feedback, in fact feedback is necessary in solid state design due to the increased non linearity of solid state devices compared to tubes. Hhmmm, I had heard that some people claimed that Bruno's Ncore amplifier modules were sensitive to noise, but I hadn't heard anything about Bruno using extensive trial and error in designing any single amplifier module. From my understanding he actually took a very scientific/mathematical approach to the fundamental design. According to him, his big breakthrough was utilizing tons of Negative Feedback in order to deal with harmonic distortion brought on by the use of low amounts of Negative Feedback[1,2,3]. I would be interested in concrete references to the "noise sensitivity" issue if any are available. Casey [1] Negative feedback in audio amplifiers: Why there is no such thing as too much[2] Negative feedback in audio amplifiers: Why there is no such thing as too much (Part 2)[3] The F-word or, why there is no such thing as too much feedback |
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Post by geebo on Dec 1, 2017 20:37:15 GMT -5
... The gen 3 is just a curiosity for me at this point. I'll wait till either Emotiva gets its head back on straight regarding its switching PS. Or if they transition to switching, then I'll just wait for the replacement company that is sure to come to occupy the niche of cheap heavy iron that Emotiva seems keen on leaving open to the competition. ... The Gen 3 for me however puts Emotiva back in the running for my next amp. Due to my feeling that the technology has matured more than enough for high quality audio, and because it’s efficiency is so much better, I had pretty much decided my next HT amp would be Class D. After seeing geebo’s idle measurements on the XPA-2 G3, and hearing Keith’s anecdotal account of the XPA-7 G3 idle rating, I saw that they compare favorably to Class D amps in efficiency. If the technology can deliver an amp that sounds good, doesn’t use more power than is needed to produce sufficient output, and doesn’t generate excess heat, then that’s what I want. I recognize from Gary Cook ’s efficiency thread, and my measurements thread, that I’m in a minority desiring an efficient amp that generates less heat, but that’s never bothered me. I’d really love it if someone would post idle power on an XPA G3 with 7, 9, or 11 channels, it seems like they all might be pretty close. The Post Your Measurements ThreadSo, they might lose you, but they might keep me, different strokes ... I will add that the SMPS is something that drew me to the Gen 3 and at the same time made me a little apprehensive about them. After living with one for three months I know my apprehension was unwarranted and I couldn't be happier. |
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Post by mgbpuff on Dec 1, 2017 20:51:29 GMT -5
... Next, Bruno Putzey - this guy developed his class D amp by the Edison method, over many years which is a dogged try, try, and then try again approach. His designs only succeed if every detail of circuit board design is just so. Any relocation or spacing change of any given component can upset the apple cart. Locating wiring to his boards must be just so, and the power supplies must be carefully located. This is a high risk and high cost way to design and that is why his and other class D amps are sold in pre- manufactured modules. This is not likely to be a viable path for Emotiva. Then there's Nelson Pass who only does analog and hates Class D. I have no objection to negative feedback, in fact feedback is necessary in solid state design due to the increased non linearity of solid state devices compared to tubes. Hhmmm, I had heard that some people claimed that Bruno's Ncore amplifier modules were sensitive to noise, but I hadn't heard anything about Bruno using extensive trial and error in designing any single amplifier module. From my understanding he actually took a very scientific/mathematical approach to the fundamental design. According to him, his big breakthrough was utilizing tons of Negative Feedback in order to deal with harmonic distortion brought on by the use of low amounts of Negative Feedback[1,2,3]. I would be interested in concrete references to the "noise sensitivity" issue if any are available. Casey [1] Negative feedback in audio amplifiers: Why there is no such thing as too much[2] Negative feedback in audio amplifiers: Why there is no such thing as too much (Part 2)[3] The F-word or, why there is no such thing as too much feedbackThis IEEE article gives a little idea about how long he worked on it and a little of his trial and error methods. It doesn't reveal that Philips tired of his pursuits of Class D. |
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Post by mgbpuff on Dec 1, 2017 21:55:48 GMT -5
Putzey is a brilliant engineer and has pioneered a unique solution to an analog pulse width modulated amplifier. You may not be able to design and sell your own version because of Putzey's patent on the design approach. This reminds me of Bob Stuart and his MQA patents - another technology little understood. |
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klinemj
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Post by klinemj on Dec 1, 2017 22:16:03 GMT -5
This IEEE article gives a little idea about how long he worked on it and a little of his trial and error methods. It doesn't reveal that Philips tired of his pursuits of Class D. I honestly don't care how long it took someone to figure something out. I just care about the result. And, going in a direction counter to the norm often takes longer....because it's all new thinking. I have done this type of long term/speculative work in my career. We have a saying..."if I don't fail at least 50% of the time, I'm not stretching far enough" For incremental improvements, a quick turnaround is expected. For breakthroughs where new theories are put to the test...it takes longer and a lot of failures. Mark |
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Post by leonski on Dec 1, 2017 23:08:19 GMT -5
Mark,
In a production enviroment when you are going for both numbers produced and quality, you've got 4 zones, if you will, for such improvement.
Easy to do with Big payback is first to do.
Easy to do with smaller payback might be next
Hard to do with larger payback. These are 'prujects' and may take some time
Hard to do with small payback. These types of issues are the last on the list. And may never be addressed. Payback is VERY small for the additional effort.
One of the best examples of 'stretching' in the last 100 years is Bell Labs. They basically were responsible for 1 patent per day, many of which had no immediate commercial or industrial use.
Research these days is more 'goal oriented' since sombody wants to make a profit, and the sooner the better.
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hemster
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Post by hemster on Dec 1, 2017 23:33:36 GMT -5
This IEEE article gives a little idea about how long he worked on it and a little of his trial and error methods. It doesn't reveal that Philips tired of his pursuits of Class D. I honestly don't care how long it took someone to figure something out. I just care about the result. And, going in a direction counter to the norm often takes longer....because it's all new thinking. I have done this type of long term/speculative work in my career. We have a saying..."if I don't fail at least 50% of the time, I'm not stretching far enough" For incremental improvements, a quick turnaround is expected. For breakthroughs where new theories are put to the test...it takes longer and a lot of failures. Mark In my line of work (Agile software development) we have a saying... "fail fast, fail often". It is not unusual to fail but we must learn, adapt and try again, quickly. Course corrections are part of the work. |
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Post by Casey Leedom on Dec 2, 2017 3:02:56 GMT -5
And similarly, in Rock Climbing, we have a saying: if you're not falling, you're not learning ...
Casey
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Post by mgbpuff on Dec 2, 2017 5:59:41 GMT -5
My experience in developing unique software and hardware for industrial purposes is that the solution must be delivered on time and in working condition. I had a 0% failure rate in 42 years of thousands of motor/controller/software projects. A 50% failure rate would put the company out of business. Admittedly, my job was in applied engineering and not research or development engineering.
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klinemj
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Post by klinemj on Dec 2, 2017 7:07:24 GMT -5
My experience in developing unique software and hardware for industrial purposes is that the solution must be delivered on time and in working condition. I had a 0% failure rate in 42 years of thousands of motor/controller/software projects. A 50% failure rate would put the company out of business. I'm not saying what one goes to the market with is 50% failure...what I am saying is that in developing something new - the attempts to make it work while in development are high and there are a lot of failures there. Once in market - yes...the failure rate must be low. And that said, in developing new code with a known language of coding or new hardware within a known hardware platform...it shouldn't take a lot of tries to get those right. Maybe there might be 1 or 2 "oops" - missed a logic loop" or something like that. Mark |
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Post by mgbpuff on Dec 2, 2017 7:18:59 GMT -5
My experience in developing unique software and hardware for industrial purposes is that the solution must be delivered on time and in working condition. I had a 0% failure rate in 42 years of thousands of motor/controller/software projects. A 50% failure rate would put the company out of business. I'm not saying what one goes to the market with is 50% failure...what I am saying is that in developing something new - the attempts to make it work while in development are high and there are a lot of failures there. Once in market - yes...the failure rate must be low. And that said, in developing new code with a known language of coding or new hardware within a known hardware platform...it shouldn't take a lot of tries to get those right. Maybe there might be 1 or 2 "oops" - missed a logic loop" or something like that. Mark Quite true! I added that my job was applied engineering rather than development or research engineering. But feedback is not new, pulse width modulation is not new, and the math behind it all is not new. The only thing new is the successful implementation and that, I think, is contentious seeing that the topology is so exacting. |
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Post by klinemj on Dec 2, 2017 7:35:28 GMT -5
I'm not saying what one goes to the market with is 50% failure...what I am saying is that in developing something new - the attempts to make it work while in development are high and there are a lot of failures there. Once in market - yes...the failure rate must be low. And that said, in developing new code with a known language of coding or new hardware within a known hardware platform...it shouldn't take a lot of tries to get those right. Maybe there might be 1 or 2 "oops" - missed a logic loop" or something like that. Mark Quite true! I added that my job was applied engineering rather than development or research engineering. But feedback is not new, pulse width modulation is not new, and the math behind it all is not new. The only thing new is the successful implementation and that, I think, is contentious seeing that the topology is so exacting. Considering that both feedback and class D were not new when Bruno P set about developing his latest, then if it were so easy to make a great sounding class D - someone should have done it long ago. That he achieved something breaking a long standing contradiction (class D is light but noisy vs. other classes of amps are heavy and low noise) tells me what he did what true R&D, not applied engineering. Now that he's done it, as the old saying goes, "everything is easy once you know how to do it". So, it may be "exacting", but it's now known...so, even if exacting, it's easy. And, it sounds great! Mark |
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Post by mgbpuff on Dec 2, 2017 7:41:13 GMT -5
Quite true! I added that my job was applied engineering rather than development or research engineering. But feedback is not new, pulse width modulation is not new, and the math behind it all is not new. The only thing new is the successful implementation and that, I think, is contentious seeing that the topology is so exacting. Considering that both feedback and class D were not new when Bruno P set about developing his latest, then if it were so easy to make a great sounding class D - someone should have done it long ago. That he achieved something breaking a long standing contradiction (class D is light but noisy vs. other classes of amps are heavy and low noise) tells me what he did what true R&D, not applied engineering. Now that he's done it, as the old saying goes, "everything is easy once you know how to do it". So, it may be "exacting", but it's now known...so, even if exacting, it's easy. And, it sounds great! Mark It's only easy if you buy it from him and he's well patented up to protect that (just like Bob Stuart and his MQA). |
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Post by klinemj on Dec 2, 2017 8:00:54 GMT -5
Considering that both feedback and class D were not new when Bruno P set about developing his latest, then if it were so easy to make a great sounding class D - someone should have done it long ago. That he achieved something breaking a long standing contradiction (class D is light but noisy vs. other classes of amps are heavy and low noise) tells me what he did what true R&D, not applied engineering. Now that he's done it, as the old saying goes, "everything is easy once you know how to do it". So, it may be "exacting", but it's now known...so, even if exacting, it's easy. And, it sounds great! Mark It's only easy if you buy it from him and he's well patented up to protect that (just like Bob Stuart and his MQA). Since he figured out the non-easy, then - he deserved to have a well-protected technology. That's why we have a patent system. Inventors are given protection from others using their inventions without their permission in exchange for teaching the world how the invention works. People can then build off that invention with yet more things...and eventually be able to make/sell/use those improvements also. Of course, he can license out the technology is he wants and make a bit more $ off it... Mark |
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