Alan Blumlein - What if?

[Barrymagrec]

What might have been the future of post war audio if instead of being killed while developing airborne radar Alan Blumlein had returned to audio development at EMI after the war? Earlier commitment to the LP by EMI management? Earlier stereo records? How might today`s HI Fi scene be different?

 

[Martyn Miles]

It might have been more scientifically based, rather than some of the rubbish spouted today. I wonder what he would have made of the stupid cable controversy. Cables costing thousands of pounds, for instance...

 

[linnfomaniac83]

It might have been more scientifically based, rather than some of the rubbish spouted today. I wonder what he would have made of the stupid cable controversy. Cables costing thousands of pounds, for instance...

I am a beliver in cables to a point, a well designed cable with good sheilding and the right electrical properties for the system will yeild better results, that is scientific fact BUT cables costing thousands is bull $H!t.

I visited a hifi dealer recently who I generally trust and has given me great service but there was something I had to dissagree with him on.

He was demonstrating a rega isis/osiris/monitor audio pl300 system using some atlas speaker cables costing £9000 making the cables by far the most expensive component, it did sound wonderfull.

He said "the cables really make this system", I replied "the really make this system poor value for money", he looked at me a little gone out so I asked him if he were to demonstrate the same system with £500 worh of chord cable and then the £9000 atlas cable would the difference in performance justify a £8500 price premium, he said he was unsure

 

[RJohan]

It might have been more scientifically based, rather than some of the rubbish spouted today.

In one of the HiFi-mags in my library, from ca 1979, the great Arthur Radford writes a story about how he worked in audio, starting in the 1930's. The gest of it is to trust your ears, that's what he had done all those years, and with great success.

So, the idea that in the good old days of many decades ago everything was 'scientifically based' is just a modern invention. Arthur and his likes used their ears, mostly because they simply didn't have the measurement instruments we take for granted today. They couldn't even do a simple THD measurement! They had to use their ears and they did it with great result.

There is of course plenty of 'scientifically based' stuff in audio today. Just look at digital that we all (nearly) uses daily with great result. No snake oil guys there.

I myself is old enough to remember when nobody bothered with 'cables'. I still don't, for the simple reason that, using my ears (and some sound reasoning) they do next to nothing.

JohanR

 

[Barrymagrec]

And I did so much hope we could have an audio thread that wasn`t just about cables....

 

[sergeauckland]

In one of the HiFi-mags in my library, from ca 1979, the great Arthur Radford writes a story about how he worked in audio, starting in the 1930's. The gest of it is to trust your ears, that's what he had done all those years, and with great success.

So, the idea that in the good old days of many decades ago everything was 'scientifically based' is just a modern invention. Arthur and his likes used their ears, mostly because they simply didn't have the measurement instruments we take for granted today. They couldn't even do a simple THD measurement! They had to use their ears and they did it with great result.

There is of course plenty of 'scientifically based' stuff in audio today. Just look at digital that we all (nearly) uses daily with great result. No snake oil guys there.

I myself is old enough to remember when nobody bothered with 'cables'. I still don't, for the simple reason that, using my ears (and some sound reasoning) they do next to nothing.

JohanR

Except that Arthur Radford made some great test instrumentation. His LDO and DMS are classics. MI made distortion measuring kit back in the '50s and '60s, so did B&K. Cossor made good oscilloscopes in the 1940s, I used to have a 1035! My first 'scope.

It's possible AR couldn't afford test equipment when he started out, but it certainly was available, and considering AR's connections with Bristol University, I'd be very surprised if he couldn't have access to measuring equipment when he needed it. AR's genius was in the design of output transformers, which managed fewer parasitics and lower leakage than other manufacturers and so allowed greater use of feedback.

S.

 

[Barrymagrec]

Except that Arthur Radford made some great test instrumentation. His LDO and DMS are classics. MI made distortion measuring kit back in the '50s and '60s, so did B&K. Cossor made good oscilloscopes in the 1940s, I used to have a 1035! My first 'scope.

It's possible AR couldn't afford test equipment when he started out, but it certainly was available, and considering AR's connections with Bristol University, I'd be very surprised if he couldn't have access to measuring equipment when he needed it. AR's genius was in the design of output transformers, which managed fewer parasitics and lower leakage than other manufacturers and so allowed greater use of feedback.

S.

Ah, the Cossor 1035 - my dad brought home a scrapper from work when I was young so I had to fix it before I could use it. That was when I found that 2 Kv paper caps could hold a charge for 2 days (and that the bleeder chain was O/C) You probably get put on the child abuse register for letting 13 year olds do that type of thing now.

 

[demotivated]

If Blumlein was about we would have 3 channel hifi - which was his preferred solution [and the best compromise]

 

[Martyn Miles]

And I did so much hope we could have an audio thread that wasn't just about cables....

Apologies for bringing up cables, but it's my main annoyance in the world of Hi-Fi. I have a scientific background and agree that the characteristics ( shielding, etc. ) of cables are important. Look at a car. All the cables, from ignition to data, are designed for purpose. A good friend, who designs amplifiers for the audio industry, agrees that listening to a product is important. The bottom line is, though, that all these things can be analysed scientifically. Don't stop listening, but be objective...

 

[Plutox]

They couldn't even do a simple THD measurement

There is an instrument that goes back (to my knowledge) to the forties called, I think, a Varley, which was an early distortion measuring set consisting of a source (a high quality stable oscillator), and a receiver (a tunable notch filter, a calibrated high gain amplifier and a high impedance AC voltmeter).

You'd calibrate it by connecting the source to the receiver, tuning the filter for the best possible null while turning up the amplifier gain. Whatever is left is, by definition, distortion. The amount of distortion is defined by the amount of gain required to achieve the same level as the source is sending. AFAIK that is the broad principle by which distortion measuring still works.

 

[sergeauckland]

There is an instrument that goes back (to my knowledge) to the forties called, I think, a Varley, which was an early distortion measuring set consisting of a source (a high quality stable oscillator), and a receiver (a tunable notch filter, a calibrated high gain amplifier and a high impedance AC voltmeter).

You'd calibrate it by connecting the source to the receiver, tuning the filter for the best possible null while turning up the amplifier gain. Whatever is left is, by definition, distortion. The amount of distortion is defined by the amount of gain required to achieve the same level as the source is sending. AFAIK that is the broad principle by which distortion measuring still works.

That's right, it's the principle on which all THD (actually THD+N) meters work. The alternative, is to used a selective amplifier that measures the amplitude of the individual harmonics, then with paper and slide rule (remember those? I still have mine) calculate the root of the sum of the squares of each harmonic to arrive at the true THD figure, excluding noise. However, each measurement was so tedious, it's no wonder that THD+N measurements very quickly took over, especially as the +N contribution was of increasingly small size.

S.

 

[Barrymagrec]

Just come across this :- http://www.amazon.co.uk/gp/product/B002NUHJSG/?tag=pinkfishmedia-21 It has fragments of Mozart symphony No.41 recorded in stereo in 1932 during the sessions for a comercial recording and Alan Blumlein in a walking, talking stereo test. It also has part of a 1937 concert recorded on plastic backed magnetic tape at the BASF factory in germany.