But all the depth and space is gone when I move the equipment away from the speakers. I'm sure it all is those lousy cables! Especially the turntable. Same thing happens when I lower the dust cover over the turntable. I like it best when the TT is really close to the woofer, just before it all takes off with the odd bass growl. It also helps to have a big TV between the speakers and a coffee table with all my remotes and some decorative bowls. And you know how much it helps to have a piano in the listening room next to the speakers.
(This is why I have a hard time talking most demos at shows seriously.)
(This is why I have a hard time talking most demos at shows seriously.)
I don't like the sound of the boxed speakers I derived from OB ( shoe boxes in LS3/5A style , was design brief ) . Everyone else does . They all wouldn't live with my OB . It is the beacon of sound I don't like . Weird thing is when I shut my eyes they almost disappear . I am sure it is they don't drive the room like a dipole . Mono sounds fabulous on them . FM also . I think above 20 dB separation I hate the sound . That can be fixed . The OB focuses the sound and should be worse . There is one sweet spot . Thing is there is sound everywhere in the house of similar tonality . It really sounds real . Hey Ho the boxes are well loved and I must not say otherwise . The really weird bit is 78's and MP3 are out of this world good and that has to be something to smile about . I am trying a 28 kHz filter as that might hold the key to this . 78's have so much depth and separation of things like the space it was in . Colleen and I listen to tons of 78's . She isn't bothered about when , just what .
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Nige, I think your laying the blame at the door of separation is completely wrong.
As I write this, I am listening to a separation of 55 dB worst case 20-20,000 Hz, and I hear is excellent spatial cues, who is sitting where, how far back, etc. My point is, separation is necessary, but it is possible that somehow its is not all the same how it was achieved.
And I would definitely suspect the amp-speaker interface. This, I beleive, is mostly down to the loudspeaker, how easy or difficult a loda it presents to the amp. Of the many amps, integrated and power, I have tried with my speakers, not one failed to present its best to it, down to the lowly supermarket Technics rated at a whopping 25 WPC into 8 Ohms.
I have no choice but to conclude that all the work my friend and I invested in making the speakers as an easy load as possible has paid off in spades. Switch the AR94s in instead of my standard speakers, and everything changes. The ARs are not a terribly difficult load, but they are much harder to drive than my stanrad, and you hear it at once. The above little Technics hasn't got a chance in gell to drive them to what they are capable of, and I do not mean only in terms of loudness.
As I write this, I am listening to a separation of 55 dB worst case 20-20,000 Hz, and I hear is excellent spatial cues, who is sitting where, how far back, etc. My point is, separation is necessary, but it is possible that somehow its is not all the same how it was achieved.
And I would definitely suspect the amp-speaker interface. This, I beleive, is mostly down to the loudspeaker, how easy or difficult a loda it presents to the amp. Of the many amps, integrated and power, I have tried with my speakers, not one failed to present its best to it, down to the lowly supermarket Technics rated at a whopping 25 WPC into 8 Ohms.
I have no choice but to conclude that all the work my friend and I invested in making the speakers as an easy load as possible has paid off in spades. Switch the AR94s in instead of my standard speakers, and everything changes. The ARs are not a terribly difficult load, but they are much harder to drive than my stanrad, and you hear it at once. The above little Technics hasn't got a chance in gell to drive them to what they are capable of, and I do not mean only in terms of loudness.
I have explored that in the past. The physical requirements are pretty much a non-starter for domestic applications. First key concept is the Haas window- Precedence effect - Wikipedia, the free encyclopedia In practice for home audio ensure that there are no reflected sounds with less than 10 mS difference from the direct sound. This means at least 5' (or around 2M) between the speakers and any reflecting surface. So its a large space. 10' works much better. Then make sure the reflecting surfaces are damped somewhat so they don't have a strong character of their own. If there is a surface closer use a sound absorbing panel with high absorption (I use at least 2" of wool batting) to absorb the radiation.
Get the equipment as far as possible from the speakers. And nearby surfaces should be carpeted or covered with pillows etc. You can hear them all.
These efforts are not difficult or expensive if you have enough space. My experiment was in a 30' wide 75' deep and 15' ceiling meeting space in an old Chicago hotel for a CES many years ago. A pair of Quad 63's well removed from the walls were magic. The recordings, of any type, were simply reproduced in 3D space with no connection to the speakers.
An American 2 car garage could be converted for less than the cost of an entry level high end speaker ($10,000) and make pretty much any speaker sound dramatically better. Very few do since its really a room about 20' wide, 12' ceiling and 30'+ deep. And pretty barren of furniture. However the removal of near field reflections makes for a really open transparent view into the sound field of the recording.
The other side of the coin is that exactly that type of reproduction is also possible with extremely conventional equipment, in a very messy, totally non-optimised listening environment - the requirement here is for the electronics to be extremely clean.
This indicates that the ear/brain is able to decode the information needed for a convincing illusion to form if the conflicting sounds are at a low enough level. And those conflicting sounds can originate in at least two sources: distortion added from the operation of the playback chain; and excess reflections generated within the listening space.
Since many people are limited, in not being able to dedicate large spaces optimised as a listening space, the improvement of the playback mechanism is probably the 'better' solution ...
Bob, should be pretty obvious, 
- right side ... if you need to focus on the sound to "see" the illusion then it ain't happening; conscious analysis of what's going on isn't necessary. In fact, to use the example of the Spinning Dancer visual illusion as a counter example - it's impossible to bypass the disappearing speakers illusion even when one mentally tries to "catch it out"; the effect is rock solid, when fully formed.
- right side ... if you need to focus on the sound to "see" the illusion then it ain't happening; conscious analysis of what's going on isn't necessary. In fact, to use the example of the Spinning Dancer visual illusion as a counter example - it's impossible to bypass the disappearing speakers illusion even when one mentally tries to "catch it out"; the effect is rock solid, when fully formed.We have a UK flag up a pole > 28 feet high to do testing . It is our anechoic chamber so as to have accurate 20 Hz measurements . We have the flag so as not to alarm the neighbours ( illegal in UK I think , not so USA , if prosecuted the TV has a field day so seldom does it happen ) . OK , in the room it is different and that is known . Data for comparisons mostly . Matt who is helping me voice the speakers seems to be able to memorize the measurements of any speaker . I met Matt via Pano suggesting I bought his spare drivers . So lucky he is not in Serbia . One day Beograd calls Dvv ( or Somerset ) . Cheltenham is less far .
Matt is slightly more LS3/5A than me . Me more Dynaco / AR . It would be lovely to offer both versions ( unlikely ) . Linn Kans , LS3/5A and Harbeth P3 are variations on a theme . The Royd Sorcerer was better than any of those to my ears .
Interesting conclusion to first speaker tests . I must not go too far with this as it is advertising to set out my table too much . As someone bringing back a brand I feel justified . My friend Martyn is making some LS3/5A clones for his twin brother . I will lend Martyn some Audio Master 3/5A for comparison measurements ( Robin Marshall ex BBC ones , He of OB statements ) . Martyn not only listened , he listen loud ( 105 dB peaks at a guess ) . That is not the usual him . The most remarkable quality is how well it worked with both AudioLab and Quad amps . In fact no good quality amp seems to dislike them . This is a happy thing and I didn't plan for it . They are almost resistive so I guess I should have expected it . We listened to Martyn and wife singing via his Neumann ribbons . This is the first time in my life I have liked the AudioLab ( pinched usually ) .
I don't like these speakers yet , but I seem to be out numbered eight to one so far . I am told Enzo Ferrari had a Mini to keep him honest , so it's not just me who is so self critical .
My full time boss seems a bit miffed I have done this . I don't think he realized I have the slightest interest in it . I have repaired 1000's of speakers over 45 years + . It would be strange not to get a feel for it . I had to test them when repaired which means I listened .
I was told mono signals " time " better . My 20 db separation is perhaps timing related ( metronome quality ) . To me 20 dB is proper stereo and the other is Ping Pong . As said it is so easy to change that . Really deep sound stage mono I adore . The stereo happens in my head . In real life mono is the sound we mostly get . It is diffuse and spacious with great depth . Our eyes make the stereo . HD TV is like hi fi . All the detail better without real life contrast .
Matt is slightly more LS3/5A than me . Me more Dynaco / AR . It would be lovely to offer both versions ( unlikely ) . Linn Kans , LS3/5A and Harbeth P3 are variations on a theme . The Royd Sorcerer was better than any of those to my ears .
Interesting conclusion to first speaker tests . I must not go too far with this as it is advertising to set out my table too much . As someone bringing back a brand I feel justified . My friend Martyn is making some LS3/5A clones for his twin brother . I will lend Martyn some Audio Master 3/5A for comparison measurements ( Robin Marshall ex BBC ones , He of OB statements ) . Martyn not only listened , he listen loud ( 105 dB peaks at a guess ) . That is not the usual him . The most remarkable quality is how well it worked with both AudioLab and Quad amps . In fact no good quality amp seems to dislike them . This is a happy thing and I didn't plan for it . They are almost resistive so I guess I should have expected it . We listened to Martyn and wife singing via his Neumann ribbons . This is the first time in my life I have liked the AudioLab ( pinched usually ) .
I don't like these speakers yet , but I seem to be out numbered eight to one so far . I am told Enzo Ferrari had a Mini to keep him honest , so it's not just me who is so self critical .
My full time boss seems a bit miffed I have done this . I don't think he realized I have the slightest interest in it . I have repaired 1000's of speakers over 45 years + . It would be strange not to get a feel for it . I had to test them when repaired which means I listened .
I was told mono signals " time " better . My 20 db separation is perhaps timing related ( metronome quality ) . To me 20 dB is proper stereo and the other is Ping Pong . As said it is so easy to change that . Really deep sound stage mono I adore . The stereo happens in my head . In real life mono is the sound we mostly get . It is diffuse and spacious with great depth . Our eyes make the stereo . HD TV is like hi fi . All the detail better without real life contrast .
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To celebrate Martyn and I went to listen to the real one of this . I love two stroke diesel engines . The real one has 32 cylinders , this 16 .
https://www.youtube.com/watch?v=sGzhcxqmX1M
https://www.youtube.com/watch?v=sGzhcxqmX1M
https://www.youtube.com/watch?v=U4c_vWpOt7M
36 cylinders as in 3's . It was the most powerful in the world at the time . English Electric also made jet aircraft and washing machines . The engine had a crossover crank system to allow the delta to work .
The engine room like an operating theatre . I am told the engines were fitted to our version of E boats . Napier supplied service pack engines as they didn't want anyone touching them . Relatively light weight so easier to fit .
36 cylinders as in 3's . It was the most powerful in the world at the time . English Electric also made jet aircraft and washing machines . The engine had a crossover crank system to allow the delta to work .
The engine room like an operating theatre . I am told the engines were fitted to our version of E boats . Napier supplied service pack engines as they didn't want anyone touching them . Relatively light weight so easier to fit .
I just heard I should be in London next year this time.
So it'll be Serbia checking out UK, methinks. You just cool the cider, lad.
I bought a Marantz just to measure it and listen to it.... very good sound accuracy and locallization -- characteristic of CFA. But only IF you have a high Z load with high effeciency speakers (which i do). But it lacks bass weight and the low level power distortion is too high because the OPS bias is very low and the bias tends to drop further when heated up which increases the THD... so low level details get lost, as well.
The single device EF OPS stage can only handle a few Amperes max (10A max rated devices).
Then there is the low SR opamp front end... a nice descrete CFA circuit after it but the damage is already done with the slow opamp(s) in front end...
Rebiasing the OPS up to 60mA helps improve low level detail (from original setting of 15mA). And replacing the IPS opamp.
THx-RNMarsh
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One of the arguments made about current dumping was that all these problems vanish when feed forward correction. Even the dumpers can be stupidly slow.
Friends who analyzed the Quad 405 say it's sound has nothing to do with it being current dumping . It is mostly the philosophy of the product that is should do well in the Pro Audio world. It is much loved as a workhorse.
Dr Ron Smith of Harwell had bothered to perfectly balance the bridge of his . He said distortion was remarkably better as was the sound. My little tests seem to endorse this. Personally I prefer 303 over 405 . 606 is OK.
From what I have read 405 is still mostly a feedback amp. If you like it gets help when above 10 kHz. remember it inverts phase.
Friends who analyzed the Quad 405 say it's sound has nothing to do with it being current dumping . It is mostly the philosophy of the product that is should do well in the Pro Audio world. It is much loved as a workhorse.
Dr Ron Smith of Harwell had bothered to perfectly balance the bridge of his . He said distortion was remarkably better as was the sound. My little tests seem to endorse this. Personally I prefer 303 over 405 . 606 is OK.
From what I have read 405 is still mostly a feedback amp. If you like it gets help when above 10 kHz. remember it inverts phase.
Er, um, Richard? What was that project called, "How To Rebuild A Marantz Product To Make It Sound Good"?
You may not know this, but Maranz products have suffered from poor op amp vices for about two decades now. They insist on NJR op amps I assume because they can get them dirt cheap, while my experience tells me to stay well away from NJR op amps.
About 4 or 5 years ago, I suggested to to a guy from Chicago who onwed a Marantz 7000 integrated amp which he insisted on keeping for some reason to try changing those op amps. He did (rather, he had them changed by a qualified technician) and was happy with what he called a "whole new ball game" sound, vastly improved. He took my advice and inserted some AD op amps. That was a classic design, typical voltage feedback stuff.
Ever since the early 90ies, I have maintained and proven many a time that the only truly meaningful tune-up of Marantz' CD players was to take out those junk NJR op amps and throw in some decent stuff. Over the years, I discovered that whatever I do and put in, in the end, OP 275 will come out sounding the best overall. Ditto for Philips CD players. I don't know why, but it never fails.
I am just guessing here, but I have a notion that's because OP 275 has very significantly shorter fall time than the NJR op amps, by a factor of 6 abd more. Or perhaps because of its Butler front end, and most probably because of both.
I think Douglas Self has not helped the situation by insisting over-biased class AB to be the worst compromise. What D S hasn't addressed is how measurements of amplifier should involve us and how we hear. My conjecture is we all of us need that first watt to be good. This might be 5 watts if low efficiency speakers. Anecdotal evidence suggests all listeners need this. Thus they buy speakers to allow it to suit a room. This could be because this is a fundamental reality of class AB . What adds weight is you saying bias reducing with temperature. D S implies that a successful bias arrangement can be made as if by component values alone. No way it can. I tried every example suggested and failed. Total respect for the author and admit I got it wrong somewhere . I suspect the heat-sinking counts in his assumptions. The maths say otherwise. If I made the mistake I am sure others will. Respect to D S in showing best practice. Perhaps his suggestion is critical ? I always thought the new Marantz company slightly directionless without it's founding fathers.
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