The power chips are good enough as is, certainly have no trouble delivering truly "invisible" speakers, and the dynamics of the Beethoven 9th.
Where the refinements need to be made is in the support mechanisms, notably the power supplies. I have seriously contemplated doing a 2400W amp just using chip amps, and blowing the windows out of a listening room or two, just as an "up yours" ...
Frank
Where the refinements need to be made is in the support mechanisms, notably the power supplies. I have seriously contemplated doing a 2400W amp just using chip amps, and blowing the windows out of a listening room or two, just as an "up yours" ...
Frank
The power chips are good enough as is, certainly have no trouble delivering truly "invisible" speakers, and the dynamics of the Beethoven 9th.
Where the refinements need to be made is in the support mechanisms, notably the power supplies. I have seriously contemplated doing a 2400W amp just using chip amps, and blowing the windows out of a listening room or two, just as an "up yours" ...
Frank
Frank, the question is whether "good enough" can be made into say "very good".
I seriously believe a FET buffer could improve the sound, it almost always does (assuming no design booboos). At the very least, it can't hurt.
Well, everyone knows the difference between "good enough" and "very good" -- I distinctly remember laboratory instruments with these markings around the scale ...
Trouble is, the ear is a strange animal - hard to know what to feed it at times! However, I reckon I've got a pretty good handle on it ... if an amp, which in my book is an alias for a complete system, allows one to put on one's "worst" recordings, the speakers stay "invisible", I can wind it up to the point just before the voltage rails clip, and then drop to an almost inaudible whisper without apparent change in tonality, and the sound remains "natural" at all times, then I would say it's "good enough". Extra would simple stuff like being capable of clean 125dB peaks vs. 118dBs, then I would up the "goodness" rating ...
Frank
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Well, everyone knows the difference between "good enough" and "very good" -- I distinctly remember laboratory instruments with these markings around the scale ...
Trouble is, the ear is a strange animal - hard to know what to feed it at times! However, I reckon I've got a pretty good handle on it ... if an amp, which in my book is an alias for a complete system, allows one to put on one's "worst" recordings, the speakers stay "invisible", I can wind it up to the point just before the voltage rails clip, and then drop to an almost inaudible whisper without apparent change in tonality, and the sound remains "natural" at all times, then I would say it's "good enough". Extra would simple stuff like being capable of clean 125dB peaks vs. 118dBs, then I would up the "goodness" rating ...
Frank
Not to get too deep into semantics, all I am suggesting, based on my admittedly very small experience, is that a discrete FET buffer COULD improve the sound somewhat.
I have to be vague because there are far too many power amp chips I haven't even seen, let alone heard, especially over the last 5 or 6 years.
hm, 95 dB speakers are on the high side of efficiency - so a 125 dB " very good" system would need 1 kW of amp?
Geddes gets 95 dB sensitivity with his Abbey, uses a 12" waveguide and B&C DE-250 compression driver - which is rated for 120 W "program power capacity"
"a very good system" requires a fire extinguisher at hand, a closet full of spare drivers?
Geddes gets 95 dB sensitivity with his Abbey, uses a 12" waveguide and B&C DE-250 compression driver - which is rated for 120 W "program power capacity"
"a very good system" requires a fire extinguisher at hand, a closet full of spare drivers?
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There are always so many variables affecting the sound, in my experience quite a number of them have to do with aspects largely ignored by most. So, using using that FET buffer may make a dramatic difference to a particular circuit, but I would try doing something other to make my significant improvements ...
Realistically, 115-120dB peaks is all one should want; check out pro shops, active monitors for a bit over $500 a pair promise this for near field listening. It just takes a little bit more sensitivity, a little more power to deliver true 125dB peaks.
Personally, I estimate I can get high quality 106dB peaks, and that's good enough for me. Subjectively, it has all the impact that I want; extra is for boasting purposes, and bigger homes ...
Edit: measurements of sound levels within a playing orchestra showed that another musician directly in front of the brass section "suffered" 125dB peaks at the biggest crescendos, the highest measured ...
Frank
Realistically, 115-120dB peaks is all one should want; check out pro shops, active monitors for a bit over $500 a pair promise this for near field listening. It just takes a little bit more sensitivity, a little more power to deliver true 125dB peaks.
Personally, I estimate I can get high quality 106dB peaks, and that's good enough for me. Subjectively, it has all the impact that I want; extra is for boasting purposes, and bigger homes ...
Edit: measurements of sound levels within a playing orchestra showed that another musician directly in front of the brass section "suffered" 125dB peaks at the biggest crescendos, the highest measured ...
Frank
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We should fight to retain class AB chips by buying them when we can . Nothing on this planet is so sensible and so cheap . LAB 47 must agree ?
And so would Marshall, a maker of guitar amps some may have heard of ...
, I reckon they use them by the truckloads ...Frank
essentially content free as far as amplifier's effect on "sound"
only have to appeal to psychoacoustics to "explain" why bad measuring amplifiers may be sometimes be tolerable to listen to
the "hearing below the noise floor" is typical audiophile BS - ignores frequency dependence, critcal band theory - I haven't seen any psychoacoustic test showing the purported "below the noise floor" resolution when a fully informed description of signals, noise and our hearing limits have pulled together in one test
only have to appeal to psychoacoustics to "explain" why bad measuring amplifiers may be sometimes be tolerable to listen to
the "hearing below the noise floor" is typical audiophile BS - ignores frequency dependence, critcal band theory - I haven't seen any psychoacoustic test showing the purported "below the noise floor" resolution when a fully informed description of signals, noise and our hearing limits have pulled together in one test
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I have a Park amplifier by Marshall . It uses TDA 2030 from memory . It sounds very like a Marshall .
The met Mr Grinrod who designed some of Marshalls best ( He was meeting Mr Kondo , if not too secret I hope , Kondo and Jim Marshall " nearly " worked together , a very long story ) . his best was when his wife was in hospital . He did it so as to distract himself from the reality of something he personally could not fix .
I repaired a Rotel RA 931 . Like a fool it was sent on it's way before finding out what the thin copper strips inside do ? The are not emitter resistors as those were 0R22 . It's bugging me now . Lovely amp . So simple and so nice . Different than when in 1995 I saw them almost every week . The bias was 2mV @ R22 . I reset it to the default value of original Rotel's 4.3mV@ R22 . I noticed that the bias peaked after 10 minutes and settle to 3.3 mV hours later ( from 4.3 ) . Did someone at Rotel UK read Douglas Self on doubling ? To me it's not correct if not to Stan Curtis original .
36 V rails ( I get 242 V typical ) . NE5532 phono , OPA2604 inter stage . Amp , generic op amp style with minimum parts . Superb layout ( puts me to shame ) . I did a bit of Dvv on it and gave some capacitors new homes . Toroid looks about 200 VA . DC offset identical 75 mV . That looks suspiciously like a choice to me ?
The met Mr Grinrod who designed some of Marshalls best ( He was meeting Mr Kondo , if not too secret I hope , Kondo and Jim Marshall " nearly " worked together , a very long story ) . his best was when his wife was in hospital . He did it so as to distract himself from the reality of something he personally could not fix .
I repaired a Rotel RA 931 . Like a fool it was sent on it's way before finding out what the thin copper strips inside do ? The are not emitter resistors as those were 0R22 . It's bugging me now . Lovely amp . So simple and so nice . Different than when in 1995 I saw them almost every week . The bias was 2mV @ R22 . I reset it to the default value of original Rotel's 4.3mV@ R22 . I noticed that the bias peaked after 10 minutes and settle to 3.3 mV hours later ( from 4.3 ) . Did someone at Rotel UK read Douglas Self on doubling ? To me it's not correct if not to Stan Curtis original .
36 V rails ( I get 242 V typical ) . NE5532 phono , OPA2604 inter stage . Amp , generic op amp style with minimum parts . Superb layout ( puts me to shame ) . I did a bit of Dvv on it and gave some capacitors new homes . Toroid looks about 200 VA . DC offset identical 75 mV . That looks suspiciously like a choice to me ?
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I always thought Bob totally sincere . Also he could tolerate Micheal Gerzon ( not known to ever have a bath ) . That allowed Bob to have all of Micheal's patents . Most people treated Michael as completely mad . It would never happen when in print because this transformed Michael . How I wish I had treated him better . Are all youngsters mildly psychopathic ? I was very caring for a youngster , the previous statement still applies . Worst of it is , it would be self interest now if had been more of a friend . For all that Michael was intellectuality a colossus and it was very intimidating . DF 96 on steroids .
I was surprised by the line - possibly a "throw-away", trying keep up enough FUD for Meridian's marketing case
most of the article dealt with digital audio CD reproduction limits - I am not doctrinaire that RedBook is "prefect" - I regularly link his resolution article, dither discussions
but the case for 44.1 pre-ringing audibility, requirement for higher sample rates still isn't convincing enough for the psychoacoustic textbooks
most of the article dealt with digital audio CD reproduction limits - I am not doctrinaire that RedBook is "prefect" - I regularly link his resolution article, dither discussions
but the case for 44.1 pre-ringing audibility, requirement for higher sample rates still isn't convincing enough for the psychoacoustic textbooks
The thing that sticks in my mind is how good the 14 Bit Meridian players sounded . Detail they shouldn't have was abundant ( and so nice / accurate ) . I wish I kept the one that was traded in cheaply as I was astonished how good it was . Forgive my typo's ( previously and often ) . The last was taking my ex to the bus station and I was late . I always compare myself with Frasier , she definitely is Lilith .
I dislike CD , so to like one is rare .
I dislike CD , so to like one is rare .
Questions for suggestions Gents ...
I want to upgrade the PSU caps in a PS-Audio amp i'm currently using, it currently using 12,000ufx4 in the psu, my options are ,
Leave whats there currently and add an addition external cap bank of 4 x68,000uf..
or
Remove current caps and install the 68K in it's place on the copper rails and remote the transformer to a separate chassis ...
Thoughts ...?
I want to upgrade the PSU caps in a PS-Audio amp i'm currently using, it currently using 12,000ufx4 in the psu, my options are ,
Leave whats there currently and add an addition external cap bank of 4 x68,000uf..
or
Remove current caps and install the 68K in it's place on the copper rails and remote the transformer to a separate chassis ...
Thoughts ...?
Remove trafo and replace with external SMPSU, use space previously occupied by trafo to install a multitude of paralleled lytics and series inductors to filter out switching hash. Be sure to install decent (segmented) additional CMchoke on mains side of SMPSU.
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