For something a little bit "spacey", try 6moons industry features: Audio Esoterica visits Kyron Audio in Australia ...
Australia seems to exude confidence these days . Never had the recession I guess ? Dipoles hey?
This is ex EPOS and Incatech importer Martin Renwick. Toyota like what he does and back him. He also makes films.
Vuelo Velo Twisted V8 | Cycle EXIFCycle EXIF
This is ex EPOS and Incatech importer Martin Renwick. Toyota like what he does and back him. He also makes films.
Vuelo Velo Twisted V8 | Cycle EXIFCycle EXIF
Me too Andrew. I went to a recording of Poulenc's the Gloria about a year ago in Oxford. I recorded Vaughan Williams Tuba Concerto there years ago and had problems with the tuba bubbling. I then realized how being a recording engineer is not easy. I did get a very good sound in the Seldonian.
The Beethoven recorded that night was the best musical experience of my life. It sounded just like 78's and the Mahler that followed like excellent CD. I never realized before that Beethoven has interplay that is 90% the music. Sure I can hear it fine. 30% is the hi fi version. Most Beethoven sounds like Joe Meek did it. Now that would be fantastic but........ My interest is did they capture what I heard that night.
I do like all music and listen to all and anything. Classical is the one that is not easy to ignore and overrides matters of taste etc. I drink mostly white wine these days yet possibly am a true expert on red wines. Classical was also true once upon a time. Now I can not accurately remember the names of music I like these days, aged 8 I was seldom wrong. I like it the same as ever. The Mendelssohn Octet being a favorite.
Just eating my porridge Andrew ( for diabetes assistance as I am borderline). Breakfast is always 12 noon for me. I now have to cook everything to ensure I don't consume hidden sugar etc. Sweeteners are no use as the brain is fooled and the poor old pancreas still works too hard. Evening is meat , cheeses and tons of vegetables all nicely cooked. Alas I still don't get to a normal level. Porridge is said by my Rabbi to be good for it. I am not Jewish but do have a Rabbi.
The Beethoven recorded that night was the best musical experience of my life. It sounded just like 78's and the Mahler that followed like excellent CD. I never realized before that Beethoven has interplay that is 90% the music. Sure I can hear it fine. 30% is the hi fi version. Most Beethoven sounds like Joe Meek did it. Now that would be fantastic but........ My interest is did they capture what I heard that night.
I do like all music and listen to all and anything. Classical is the one that is not easy to ignore and overrides matters of taste etc. I drink mostly white wine these days yet possibly am a true expert on red wines. Classical was also true once upon a time. Now I can not accurately remember the names of music I like these days, aged 8 I was seldom wrong. I like it the same as ever. The Mendelssohn Octet being a favorite.
Just eating my porridge Andrew ( for diabetes assistance as I am borderline). Breakfast is always 12 noon for me. I now have to cook everything to ensure I don't consume hidden sugar etc. Sweeteners are no use as the brain is fooled and the poor old pancreas still works too hard. Evening is meat , cheeses and tons of vegetables all nicely cooked. Alas I still don't get to a normal level. Porridge is said by my Rabbi to be good for it. I am not Jewish but do have a Rabbi.
Oatmeal porridge with cinnamon i presume Nige, you need to couple that with some daily activity..... 
As to class -a , the biggest difference is in the high frequency , this is where its easily determine and most noticeable when comparing amplifiers of different classes. Brushes turns into chicken scratch, sweetness on the upper range of sopranos and violins are lost , dull to a bit dry is another tell tale when leaving class -a. At the other extreme is class -D , this one captures the jump of live music the best , music comes alive here , but with big issues in the upper midrange and top end hardness , pretty unnatural sounding here..
Best compromise (its all a compromise) is somewhere in-between , enuff class-a To keep the upper ranges happy and enuff class-b to keep the music alive...
Franky , take your best PC SOUND ever heard , times it by 1000 , now do the comparison .
As to class -a , the biggest difference is in the high frequency , this is where its easily determine and most noticeable when comparing amplifiers of different classes. Brushes turns into chicken scratch, sweetness on the upper range of sopranos and violins are lost , dull to a bit dry is another tell tale when leaving class -a. At the other extreme is class -D , this one captures the jump of live music the best , music comes alive here , but with big issues in the upper midrange and top end hardness , pretty unnatural sounding here..
Best compromise (its all a compromise) is somewhere in-between , enuff class-a To keep the upper ranges happy and enuff class-b to keep the music alive...
Franky , take your best PC SOUND ever heard , times it by 1000 , now do the comparison .
I just don't hear most of the differences everyone talks about, especially in the bass.
I have never done an IC AB or ABX listening test, so have nothing to add and personally never purchase equipment based on IC in or not chosen, If it works, who gives a chit, really ! I'm only interested in end results performance, my bias(s) is only to realism of sound and performance, i dont really care whats used to get me there.
Same for the digital vs analog performance, bad sounding LP's are shown the door , straight to Ebay, i only keep those with max performance and good music, the combination has to be right, same for CD's. Last night i spent 20 mins cleaning the R to R and played one of my 15ips master copies, as enjoyable as any of the others, Flaws, absolutely some tape drag after 25-30 mins (belts and more servicing needed now) but man glorious dynamics and realism of sound gives up nothing to my TT or CD player, no dreaded tape hiss to boot.
Tapes are cost prohibitive, so very limited amount to go to, when listening, the last time i used was about 1 yr ago, if buying pre-recorded stick to Decca, the others are a waste of time IMO, so i have very few that meet my ratio to sound performance and music, tuff combination
. luckily i have a few contacts still left in the music business from past involvement and can "get " some treasures from time to time. As to tape deterioration , i have a few 40 yr old Decca pre-recorded 7.5 ips 4 track , that's pretty good, one or two notch's below CD quality for dynamics, but is so glorious in the mid-range , top (yes top, bass is the let down) and space it's a treat to listen to, i have yet for anyone to hear them and not feel puzzled as to why tape formats were not more popular in it's day ... Anyway sorting thru some Telarc stuff today ........
Anybody want to run with the 3 D nature of electricity? I think I was on my own trip with that yesterday.
Years ago I worked with a video company. I was brought along as the sound man. I was shown the Sony class D amp. I was asked my opinion of the hottest UK gear. I said Naim and Linn. Not the sound , just the mindset. Apparently that was enough and a system was bought from Grahams in London to ship to Japan.
What Sony did was see how the concept worked and did it their way. I think that is very intelligent.
How Sony talked about it was that an amplifier is bathed in magnetic fields from the transformer. As long as nothing moves that is reasonably OK. Sony identified that the vibration of the transformer and speaker vibration cause small error voltages in the components. One needs to put sensors on things to know more. Just saying I do an excellent job doesn't mean you do. I usually get shown superb casework and thick PCB's . That's all very nice but isn't proof. Anyone who has scientifically designed turntables will know what I mean. As said before the measured effect were at - 120 dB.
I was thinking Mr Dvv. Place transformer under amp in it's own box. Hole into amp for AC LT in. Squash-balls or whatever isolation = Super amp. The AC path might even be shorter than usual.
An RAF guy showed an experiment using reconfigured aircraft test equipment. This re-digitized the signal and showed error difference in the time domain between in and out. We poked fun and found real problems in the assumptions. However what stayed in my head is the mechanically isolated amplifier did look almost exactly as the original. He said how this is used on aircraft and how vital it is, stress failure I think. Problem is I was in a world of my own by then and didn't listen. Wish I had.
Thanks for food advice. Dr says the same.
Years ago I worked with a video company. I was brought along as the sound man. I was shown the Sony class D amp. I was asked my opinion of the hottest UK gear. I said Naim and Linn. Not the sound , just the mindset. Apparently that was enough and a system was bought from Grahams in London to ship to Japan.
What Sony did was see how the concept worked and did it their way. I think that is very intelligent.
How Sony talked about it was that an amplifier is bathed in magnetic fields from the transformer. As long as nothing moves that is reasonably OK. Sony identified that the vibration of the transformer and speaker vibration cause small error voltages in the components. One needs to put sensors on things to know more. Just saying I do an excellent job doesn't mean you do. I usually get shown superb casework and thick PCB's . That's all very nice but isn't proof. Anyone who has scientifically designed turntables will know what I mean. As said before the measured effect were at - 120 dB.
I was thinking Mr Dvv. Place transformer under amp in it's own box. Hole into amp for AC LT in. Squash-balls or whatever isolation = Super amp. The AC path might even be shorter than usual.
An RAF guy showed an experiment using reconfigured aircraft test equipment. This re-digitized the signal and showed error difference in the time domain between in and out. We poked fun and found real problems in the assumptions. However what stayed in my head is the mechanically isolated amplifier did look almost exactly as the original. He said how this is used on aircraft and how vital it is, stress failure I think. Problem is I was in a world of my own by then and didn't listen. Wish I had.
Thanks for food advice. Dr says the same.
I just don't hear most of the differences everyone talks about, especially in the bass.
Excuse the repetion if I've said this already, but I find literally ALL op amps sound better, from some to a hell of a lot, when followed by a dicrete current booster. Nothing fancy, mind you, say a pair of MPSA 06/56 trannies is just fine for line level apps. BC 639/640 are even better.
Now, that in itself wouldn't surprise me too much, but what does suprise me is when that same thing happens to op amps rated for "high output current". I would expect them to stay more or less the same, but no, they sound better as well.
I am not talking about relatively low load impedances, like 600 Ohms and below, I am talking about loads of 1k and above.
For very low load impedances, like 30 Ohms and below, a driver pair of MPSA 06/56, driving plain vanilla BD 139/140, will serve as an excellent headphone current boster to drive just about anything you care to call a headphone, right down to 8 Ohms (however, at headphone levels only). If necessary, to ear splitting levels, not too hard on cans, given their tremendous efficiencies.
I tried it with AD826 and the venerable old OPA 37 op amps, and it worked not just "fine", but really, really well. This is why I asked you some time ago about AD829, it has the added benefit of relatively low noise, and I have about 30 of them at hand.
Also, I find that as unity gain buffers, some op amps are a godsend.
Just my 2 cents' worth.
The instrumentation to look at vibration or magnetic fields is not that exotic anymore, thanks to eBay and the short economic life of test equipment in the aerospace industries. However understanding and exploiting it is still a reach for many in this industry. It also gets confounded with magic rocks and voodoo science so it just has not gone far. I remember that the first Audionote Ongaku had a severe hum problem. That did not stop customers from laying out $80K big ones for it.
Vibration isolation of a transformer is not difficult. Its really essential when building a self powered subwoofer. Controlling the magnetic fields is also straightforward. Designing a tape recorder without looking carefully at the stray fields will be a disaster. These are not new problems, more like lost art.
Vibration isolation of a transformer is not difficult. Its really essential when building a self powered subwoofer. Controlling the magnetic fields is also straightforward. Designing a tape recorder without looking carefully at the stray fields will be a disaster. These are not new problems, more like lost art.
Wayne, as Scott will probably be able to expain better, modern op amps are far removed from what gave the op amps a bad name in audio. This applies mostly to the ancient 741 op amp, good for some things, but not really suited to audio.
When Signetics introduced the NE 5xxx family, things started to change. I don't like that opne myself, but I readily admit I have heard it applied with great prowess in some wildly expensive devices, like Accuphase CD players.
Then I discovere Analog Devices op amps, namely OP 275, then AD826 and so forth. This was a whole new ball game. When applied properly, with good bypassing and when not wildly stressed, I discovered that they were capable of a really, REALLY good sound. For years, I wondered what was it about the AD amps that enabled them to sound better than almost all others, and in the end, right or wrong, I settled on the theory that this was so because of their incredibly short settling times.
We alwas ramble on about fast rise times and high voltage slew rates, but few are even willing to consider settling time as a real world phenomenon. There is no way an op amp with a settling time (as the opposite of rise times) of 2,000 to 1,500 nS is going to sound better than another op amp with a settling time of less than 90 nS.
I'd love to be able to pat myself on the shoulder for being a smart cookie, but the truth is I had significant help in that direction. In the late 70ies, I came across that Grman made LAS Mega 1 power amp, which made much ado about settling times. Anyway, I made a working model, and by George, it did sound better than most and in fact, better than I ever expected it to. So I cconcluded there was substance in that story.
Around that time, I read an interview with Keith Johnson of Spectral. who also went on at length about settling times. So I put one and one together.
These days, when testing a possible model of interest in the simulator, I spend around 60% of the time working with settling times under various conditions, and especially difficult load conditions. I find it's not really too hard to start out with even wild slew rates, extreme bandwidths and so forth, but getting the settling of a suquare wave to be short and well behaved IS very hard (little overshoot, little wobblig upon settling, small tilt, etc).
I think I'm on to something, because every time it turned out right, the general sound was above average. Things turn hairy when you start playing with 2 Ohm loads and a phase shift of -45 degrees, but then, that's the chalenge.
Not that it was an awful lot of amps, mind you, no more than 20 or so over the last 30 years, and most remained in prototype form.
When Signetics introduced the NE 5xxx family, things started to change. I don't like that opne myself, but I readily admit I have heard it applied with great prowess in some wildly expensive devices, like Accuphase CD players.
Then I discovere Analog Devices op amps, namely OP 275, then AD826 and so forth. This was a whole new ball game. When applied properly, with good bypassing and when not wildly stressed, I discovered that they were capable of a really, REALLY good sound. For years, I wondered what was it about the AD amps that enabled them to sound better than almost all others, and in the end, right or wrong, I settled on the theory that this was so because of their incredibly short settling times.
We alwas ramble on about fast rise times and high voltage slew rates, but few are even willing to consider settling time as a real world phenomenon. There is no way an op amp with a settling time (as the opposite of rise times) of 2,000 to 1,500 nS is going to sound better than another op amp with a settling time of less than 90 nS.
I'd love to be able to pat myself on the shoulder for being a smart cookie, but the truth is I had significant help in that direction. In the late 70ies, I came across that Grman made LAS Mega 1 power amp, which made much ado about settling times. Anyway, I made a working model, and by George, it did sound better than most and in fact, better than I ever expected it to. So I cconcluded there was substance in that story.
Around that time, I read an interview with Keith Johnson of Spectral. who also went on at length about settling times. So I put one and one together.
These days, when testing a possible model of interest in the simulator, I spend around 60% of the time working with settling times under various conditions, and especially difficult load conditions. I find it's not really too hard to start out with even wild slew rates, extreme bandwidths and so forth, but getting the settling of a suquare wave to be short and well behaved IS very hard (little overshoot, little wobblig upon settling, small tilt, etc).
I think I'm on to something, because every time it turned out right, the general sound was above average. Things turn hairy when you start playing with 2 Ohm loads and a phase shift of -45 degrees, but then, that's the chalenge.
Not that it was an awful lot of amps, mind you, no more than 20 or so over the last 30 years, and most remained in prototype form.
Demian, just a quick report.
I am currently experimenting with your advice on letting those differential input FETs rip. You suggested "near to 5 mA per trannie", but I started out with 2 mA and worked my way upwards.
You might remember my note that 2SK170 was chosen not because it's the best FET around, but because of its availability and the fact that Toshiba still seems to be making them. I know it was used in some commercial products in its day, but for me, the overriding factor was the fact that it is locally available, either off the shelf, or on order. Things are rapidly improving on the local market, so perhaps soon there will be opportunity to find even better suited models.
Anyway, thus far, I got the best results overall when the bias is 3.7 mA per transistor, it really slips into its role like a glove.
Since they are in a cascode connection, with two 2SC2240 trannies above them, at which voltage would you drive them from their dedicated supply? I have seen anything from say 6 to 15 V - what's your take on this?
I am currently experimenting with your advice on letting those differential input FETs rip. You suggested "near to 5 mA per trannie", but I started out with 2 mA and worked my way upwards.
You might remember my note that 2SK170 was chosen not because it's the best FET around, but because of its availability and the fact that Toshiba still seems to be making them. I know it was used in some commercial products in its day, but for me, the overriding factor was the fact that it is locally available, either off the shelf, or on order. Things are rapidly improving on the local market, so perhaps soon there will be opportunity to find even better suited models.
Anyway, thus far, I got the best results overall when the bias is 3.7 mA per transistor, it really slips into its role like a glove.
Since they are in a cascode connection, with two 2SC2240 trannies above them, at which voltage would you drive them from their dedicated supply? I have seen anything from say 6 to 15 V - what's your take on this?
Why is feedback negative .....
Spent the afternoon sorting out my Telarc CD's , been awhile so re familiarizing myself with them made for a good afternoon , also got a chance to try out my made up 4 conductor flat copper speaker cable , hope to have some measured results for nuetron to look at later this week , then a full speaker cable shoot out next week , ( 5 different Prs) it will be ABX of course, that is , I will be drinking Guiness with an unknown catalyst , the X factor ...
Telarc 1-10, sorted , settling down now for the USA vs Portugal match, here's to our 2nd round go thru ....
Spent the afternoon sorting out my Telarc CD's , been awhile so re familiarizing myself with them made for a good afternoon , also got a chance to try out my made up 4 conductor flat copper speaker cable , hope to have some measured results for nuetron to look at later this week , then a full speaker cable shoot out next week , ( 5 different Prs) it will be ABX of course, that is , I will be drinking Guiness with an unknown catalyst , the X factor ...
Telarc 1-10, sorted , settling down now for the USA vs Portugal match, here's to our 2nd round go thru ....
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