Home |
Search |
Today's Posts |
#41
![]()
Posted to rec.audio.opinion,rec.audio.tubes
|
|||
|
|||
![]() "Pooh Bear" wrote in message ... " wrote: not much has changed in the last.... 35 years for solid-state excepting around the edges. You are JOKING ! You can't understand much about modern solid state design. Even the true complementary pair was essentially unknown 35 yrs ago. And that's for starters ! 35 years ago was 1971, and I had been building and repairing SS amps for about 8 years at the time. The true complementary pair was well-known and widely used in 1971. For example, they were widely used as drivers for quasi-complementary output stages. Common part numbers were 2N3053 and 2N4037 if memory serves. There were some issues with the costs of high powered complementary pairs, but their use was well-known. Bart Locanthi is well-known for his design of the full complementary "T circuit" which appeared in a JBL power amp in the mid - 1960s. Please see this 1967 article http://users.ece.gatech.edu/~mleach/.../tcir/tcir.pdf My recollection is that the amp was new on the market at the time this article was published. Speakers will use better materials (sometimes) and tighter tolerances (sometimes), but their essential function is unchanged. That the better materials and tighter tolerances make them more efficient is a very good thing. Also better materials for magnets. What about the use of modern materials to reduce cone break up ? Or at least control it. Not to mention in all aspects of engineering - the use of CAD / somputer modelling to optimise designs. Agreed. Circuit modeling has greatly assisted the design of low distortion circuits. |
#42
![]()
Posted to rec.audio.opinion,rec.audio.tubes
|
|||
|
|||
![]() "Pooh Bear" wrote in message ... " wrote: What about the use of modern materials to reduce cone break up ? Not to mention in all aspects of engineering - the use of CAD / somputer modelling to optimise designs Yikes.... I have a 1969-executed-in-1971 design sitting on my bench with "true complementary pair" outputs. That would be a very early example indeed. Sadly not of much help given the following info. That it also used interstage transformers and other Jurassic-vintage throwbacks is not relevant to your statement. Actually it is. It shows that such Jurassic designs were still being implemented in 1971 ! Kinda blows that 'no advances in the last 35 yrs' claim out the window nicely ! Check this one out: http://users.ece.gatech.edu/~mleach/.../tcir/tcir.pdf Cones that break up under any amplifier power below clipping are poorly designed whether in 1951 or 2021. Why even suggest otherwise? Cones break up *way* below clipping power. Just look at typical HF performance. Cone break up is a linear process. It happens at all power levels. CAD is a method, not a design. Computers model where previously actual experiments had to take place. And so fast that many possible iterations can be tried where previously it was totally impractical. It *has* revolutionised design in every single branch of engineering. Now, cutting directly to the chase... if an amplifier will produce a flat response at say.... 60 watts/rms from say.... 5hz - 50khz, at less than say.... 0.25THD, with a S/N ratio of 90dB-or-better, it is a pretty good design... maybe?? It's pretty dated. Modern PA amps do far better. 0.25% THD hardly qualifies as a pretty good design these days. It's hard for a competent designer to exceed 0.025% today even when cutting costs. Agreed. Then there is the matter of costs. Amps like the Berhinger A500 at under $200 provide clean power and tremendous value. |
#43
![]()
Posted to rec.audio.opinion,rec.audio.tubes
|
|||
|
|||
![]() "Pooh Bear" wrote in message ... Arny Krueger wrote: "Pooh Bear" wrote in message ... Arny Krueger wrote: Brat's a tubie, but now he wants us to think that hes' a conoisseur of SS amps with his crack about my USA 400. It is a perplexing choice of amplifier IMHO ! Why? I have in the past rated that style of QSC design as being somewhat 'agricultural' ! I could elaborate at considerable length. You might not like it though. Trouble is, I know how that design does in straight wire bypass tests. Indeed, how that circuit sounds in a straight wire bypass test has been posted for all to hear: http://www.pcabx.com/product/usa-850/index.htm Why not check out one of those Behringer A500s ? I'm probably going to buy some A500s for church. Take one home and try it there as well then. What sounds better than an amp that is indistinguishable from a straight wire? |
#44
![]()
Posted to rec.audio.opinion,rec.audio.tubes
|
|||
|
|||
![]() Arny Krueger wrote: "Pooh Bear" wrote in message ... " wrote: not much has changed in the last.... 35 years for solid-state excepting around the edges. You are JOKING ! You can't understand much about modern solid state design. Even the true complementary pair was essentially unknown 35 yrs ago. And that's for starters ! 35 years ago was 1971, and I had been building and repairing SS amps for about 8 years at the time. The true complementary pair was well-known and widely used in 1971. For example, they were widely used as drivers for quasi-complementary output stages. Common part numbers were 2N3053 and 2N4037 if memory serves. As *drivers* !!!!!!!!!!! Please pay attention Arny ! I said ' complementary output ' - NOT - ' quasi-complementary output' ! There's a HUGE difference.Not least in the sound. There were some issues with the costs of high powered complementary pairs, but their use was well-known. Bart Locanthi is well-known for his design of the full complementary "T circuit" which appeared in a JBL power amp in the mid - 1960s. Please see this 1967 article http://users.ece.gatech.edu/~mleach/.../tcir/tcir.pdf My recollection is that the amp was new on the market at the time this article was published. I may get round to reading that since you recommend it. The simple truth however is that it was device technology advances that made proper fully-complementary outputs viable only in the mid 70s. Speakers will use better materials (sometimes) and tighter tolerances (sometimes), but their essential function is unchanged. That the better materials and tighter tolerances make them more efficient is a very good thing. Also better materials for magnets. What about the use of modern materials to reduce cone break up ? Or at least control it. Not to mention in all aspects of engineering - the use of CAD / somputer modelling to optimise designs. Agreed. Circuit modeling has greatly assisted the design of low distortion circuits. It's actually a fascinating area. As long ago as 1989 I was using Mathcad to create my own models for amplifier gain/phase/stability calculations. Today's off the shelf packages make it so much easier but the user may not fully understand the underlying principles any more though. Graham |
#45
![]()
Posted to rec.audio.opinion,rec.audio.tubes
|
|||
|
|||
![]() Arny Krueger wrote: "Pooh Bear" wrote in message ... Arny Krueger wrote: "Pooh Bear" wrote in message ... Arny Krueger wrote: Brat's a tubie, but now he wants us to think that hes' a conoisseur of SS amps with his crack about my USA 400. It is a perplexing choice of amplifier IMHO ! Why? I have in the past rated that style of QSC design as being somewhat 'agricultural' ! I could elaborate at considerable length. You might not like it though. Trouble is, I know how that design does in straight wire bypass tests. And I know how 'badly' it measures ( for an SS amp ! ). Crossover in particular is truly horrid. Not to mention a bag of other issues I have with that style of QSC architecture. Indeed, how that circuit sounds in a straight wire bypass test has been posted for all to hear: http://www.pcabx.com/product/usa-850/index.htm Why not check out one of those Behringer A500s ? I'm probably going to buy some A500s for church. Take one home and try it there as well then. What sounds better than an amp that is indistinguishable from a straight wire? I had a feeling you might say that. I'm unconvinced of the results of your tests. I've heard those QSCs and one reason I call them agricultural is 'cos they actually sound it. Read into that whatever you like about the ear's ability to discern non-linearities ! Graham |
#46
![]()
Posted to rec.audio.opinion,rec.audio.tubes
|
|||
|
|||
![]() "Pooh Bear" wrote in message ... Arny Krueger wrote: "Pooh Bear" wrote in message ... Arny Krueger wrote: "Pooh Bear" wrote in message ... Arny Krueger wrote: Brat's a tubie, but now he wants us to think that hes' a conoisseur of SS amps with his crack about my USA 400. It is a perplexing choice of amplifier IMHO ! Why? I have in the past rated that style of QSC design as being somewhat 'agricultural' ! I could elaborate at considerable length. You might not like it though. Trouble is, I know how that design does in straight wire bypass tests. And I know how 'badly' it measures ( for an SS amp ! ). Crossover in particular is truly horrid. You obviously measured a different amp than I did. Not to mention a bag of other issues I have with that style of QSC architecture. I'm interested. Indeed, how that circuit sounds in a straight wire bypass test has been posted for all to hear: http://www.pcabx.com/product/usa-850/index.htm Why not check out one of those Behringer A500s ? I'm probably going to buy some A500s for church. Take one home and try it there as well then. What sounds better than an amp that is indistinguishable from a straight wire? I had a feeling you might say that. Fact is, the amp passes tough blind listening tests. I'm unconvinced of the results of your tests. I've heard those QSCs and one reason I call them agricultural is 'cos they actually sound it. Read into that whatever you like about the ear's ability to discern non-linearities ! Listen for yourself. |
#47
![]()
Posted to rec.audio.opinion,rec.audio.tubes
|
|||
|
|||
![]() "Pooh Bear" wrote in message ... Arny Krueger wrote: "Pooh Bear" wrote in message ... " wrote: not much has changed in the last.... 35 years for solid-state excepting around the edges. You are JOKING ! You can't understand much about modern solid state design. Even the true complementary pair was essentially unknown 35 yrs ago. And that's for starters ! 35 years ago was 1971, and I had been building and repairing SS amps for about 8 years at the time. The true complementary pair was well-known and widely used in 1971. For example, they were widely used as drivers for quasi-complementary output stages. Common part numbers were 2N3053 and 2N4037 if memory serves. As *drivers* !!!!!!!!!!! You never said complementary pair of what. However below, I show a amp design from 1967 below that had complementary pre-drivers, drviers, and outputs. Please pay attention Arny ! Say what you mean. I said ' complementary output ' - NOT - ' quasi-complementary output' ! There's a HUGE difference.Not least in the sound. Actually, the post I responded to does not contain the word "output" or any synonyms. There were some issues with the costs of high powered complementary pairs, but their use was well-known. Bart Locanthi is well-known for his design of the full complementary "T circuit" which appeared in a JBL power amp in the mid - 1960s. Please see this 1967 article http://users.ece.gatech.edu/~mleach/.../tcir/tcir.pdf My recollection is that the amp was new on the market at the time this article was published. I may get round to reading that since you recommend it. It proves my point, including outputs. The simple truth however is that it was device technology advances that made proper fully-complementary outputs viable only in the mid 70s. Check my reference which is clearly dated 1967. Speakers will use better materials (sometimes) and tighter tolerances (sometimes), but their essential function is unchanged. That the better materials and tighter tolerances make them more efficient is a very good thing. Also better materials for magnets. What about the use of modern materials to reduce cone break up ? Or at least control it. Not to mention in all aspects of engineering - the use of CAD / somputer modelling to optimise designs. Agreed. Circuit modeling has greatly assisted the design of low distortion circuits. It's actually a fascinating area. As long ago as 1989 I was using Mathcad to create my own models for amplifier gain/phase/stability calculations. Today's off the shelf packages make it so much easier but the user may not fully understand the underlying principles any more though. In 1965 I was writing Fortran programs that simulated the nonlinear performance of transistors. I accurately predicted the distortion of an emitter follower for example. |
#48
![]()
Posted to rec.audio.opinion,rec.audio.tubes
|
|||
|
|||
![]() "Arny Krueger" wrote in message . .. Indeed, how that circuit sounds in a straight wire bypass test has been posted for all to hear: http://www.pcabx.com/product/usa-850/index.htm Why not check out one of those Behringer A500s ? I'm probably going to buy some A500s for church. Take one home and try it there as well then. What sounds better than an amp that is indistinguishable from a straight wire? Might as well just save some money and just buy the wire!~ -- Posted via NewsDemon.com - Premium Uncensored Newsgroup Service -------http://www.NewsDemon.com------ Unlimited Access, Anonymous Accounts, Uncensored Broadband Access |
#49
![]()
Posted to rec.audio.opinion,rec.audio.tubes
|
|||
|
|||
![]() Arny Krueger wrote: "Pooh Bear" wrote in message ... Arny Krueger wrote: "Pooh Bear" wrote in message ... " wrote: not much has changed in the last.... 35 years for solid-state excepting around the edges. You are JOKING ! You can't understand much about modern solid state design. Even the true complementary pair was essentially unknown 35 yrs ago. And that's for starters ! 35 years ago was 1971, and I had been building and repairing SS amps for about 8 years at the time. The true complementary pair was well-known and widely used in 1971. For example, they were widely used as drivers for quasi-complementary output stages. Common part numbers were 2N3053 and 2N4037 if memory serves. As *drivers* !!!!!!!!!!! You never said complementary pair of what. " complementary output " has a *very* clear definition as far as I'm concerned. That's why your example is called a " quasi-complementary output ". No possibility of misunderstanding at all. However below, I show a amp design from 1967 below that had complementary pre-drivers, drviers, and outputs. Please pay attention Arny ! Say what you mean. Pay attention to detail. I said ' complementary output ' - NOT - ' quasi-complementary output' ! There's a HUGE difference.Not least in the sound. Actually, the post I responded to does not contain the word "output" or any synonyms. Now you're being obtuse. Anyone with any relevant knowledge would understand full well what I was referring to ! Graham |
#50
![]()
Posted to rec.audio.opinion,rec.audio.tubes
|
|||
|
|||
![]() Poopie said to the Krooborg: Now you're being obtuse. I can't believe it, Poopie -- you actually said something accurate. Anyone with any relevant knowledge would understand full well what I was referring to ! Maybe, but you've now entered the "debating trade" zone. In this peculiar dimension, your human values of communication are meaningless. Clarity of language is subordinate to Krooglish. Logic is supplanted by reflexive contradiction. Argumentation replaces facts, knowledge is subsumed by lying, and religion takes supreamacy over science. Don't go too far without a guide, Poopie. Even a lesser 'borg has something to lose in the "debating trade" zone. |
Reply |
|
Thread Tools | |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
Speaker impedance: Quad ESL, Lowther horns -- again | Audio Opinions | |||
Bruce Edgar on Horns...And Amps. | Audio Opinions | |||
Constant Directivity Horns, "Radial" vs. Flat Front, etc. | Pro Audio | |||
FS - ELECTRO-VOICE SENTRY IV MIDRANGE HORNS, CROSSOVERS AND ST-350A TWEETERS | Marketplace | |||
FS - ELECTRO-VOICE SENTRY IV MIDRANGE HORNS, CROSSOVERS AND ST-350A TWEETERS | Pro Audio |