I want to make stereo widener.
All I have found are schematics that remove center material. I want to add that to center material, not to lose it 🙂
I knwo that it can be done because I had an Aiwa cassete player that has one button to add stereo wide and it still sounds great, of course, it depends on music material.
I have been testing numerous combinations but can not find the right one
All I have found are schematics that remove center material. I want to add that to center material, not to lose it 🙂
I knwo that it can be done because I had an Aiwa cassete player that has one button to add stereo wide and it still sounds great, of course, it depends on music material.
I have been testing numerous combinations but can not find the right one
I think its pretty much the same effect those fake surround sound winamp plugins uses, adding phase shift and such.
I know for all those software thingies but I need hardware version 🙂
I have just seen schematics for Aiwa and they use some special circuit for what they call "Q sound". It is MM1434 ic. I'm thinking of making my version of "Q sound" with TL084 or similar.
I have just seen schematics for Aiwa and they use some special circuit for what they call "Q sound". It is MM1434 ic. I'm thinking of making my version of "Q sound" with TL084 or similar.
Even JLH had a version, it's published here in basic form by Paul Kemble as "image width module". Many magazines and manufacturers copied it back then. A Paul Kemble web page - John Linsley Hood preamp designs.
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One simple way to increase width is to make 'mid' and 'side' signals (M,S) then apply gain only to 'side' and re-combine into L and R again. Michael Gerzon played around with applying filtering to the 'side' signal I seem to recall, so you can try making the width frequency dependent.
Mid = 0.5(L+R) ; Side = 0.5(L-R)
Mid = 0.5(L+R) ; Side = 0.5(L-R)
hardware version ?
Play with waveguides around the tweeters
Also midrange , if any , although it may be too difficult to make
a perfect constant directivity device .
Genelec 1034B is a Powerful Control Room Monitor System
Play with waveguides around the tweeters
Also midrange , if any , although it may be too difficult to make
a perfect constant directivity device .
Genelec 1034B is a Powerful Control Room Monitor System
I want to make stereo widener.
All I have found are schematics that remove center material. I want to add that to center material, not to lose it 🙂
I knwo that it can be done because I had an Aiwa cassete player that has one button to add stereo wide and it still sounds great, of course, it depends on music material.
I have been testing numerous combinations but can not find the right one
Basically you want to vary the differences between the channels. In TV we vary the chroma saturation by changing the amplitude of the chroma difference signals before re-matrixing back to RGB. You can do the same thing in audio by converting your L and R signals by summing to L+R and L-R. Varying the amplitude of L-R before re-matrixing back to L and R will accentuate or minimize the channel differences - expanding or contracting the sound field. It's just a few opamps and resistors and a pot for the L-R. What Abraxalito said.
I don't know specifically about the Aiwa but often times the stereo 'wide' only inverts the phase of one channel. Pretty hokey.
G²
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Try reversing the leads on one of your speakers. Just for an experiment. Out of phase speakers tend to result in a spacey sound that can seem wider than normal stereo. And inverting a channel is just the sort of simple thing one push button can do without adding much to the cost of a product.
By hardware version I meant active version, with op amps. Tekko has mentioned winamp and software, so I meant to say that I don't need it for computer, I need it for my future boombox 🙂
I'm looking at those John Linsley Hood preamp designs and have found something interesting to try.
I think that aiwa has something similar packed in one chip. I'm sure that it is not fake surround. It really adds more left and more right without loosing bass or anything in the middle.
I'll make that JLH version and give it a try 🙂
I'm looking at those John Linsley Hood preamp designs and have found something interesting to try.
I think that aiwa has something similar packed in one chip. I'm sure that it is not fake surround. It really adds more left and more right without loosing bass or anything in the middle.
I'll make that JLH version and give it a try 🙂
Hi
Another design for a width control is the one used by Carver in the C1 and 4000 pre amps. The schematics are available on Hi Fi engine along with the full service manuals.
Don
Another design for a width control is the one used by Carver in the C1 and 4000 pre amps. The schematics are available on Hi Fi engine along with the full service manuals.
Don
Hi,
The circuit is called a "shuffler", and was quite common is radio stations.
You add and substract left and right to get sum and difference signals.
Changing the relative gain of the difference channel then becomes a
"width" control, less gain, less width, and more gain more width.
You then add and subtract the S&D signals to get back to stereo.
Advanced messing around includes variable tone controls / graphic EQ,
though a good idea is to limit the difference channel to frequencies
above where the speaker spacing indicates out of phase signals
will substantially cancel and just pointlessly sap power and SPL.
This frequency is a lot higher for a boombox than stereo speakers.
rgds, sreten.
The circuit is called a "shuffler", and was quite common is radio stations.
You add and substract left and right to get sum and difference signals.
Changing the relative gain of the difference channel then becomes a
"width" control, less gain, less width, and more gain more width.
You then add and subtract the S&D signals to get back to stereo.
Advanced messing around includes variable tone controls / graphic EQ,
though a good idea is to limit the difference channel to frequencies
above where the speaker spacing indicates out of phase signals
will substantially cancel and just pointlessly sap power and SPL.
This frequency is a lot higher for a boombox than stereo speakers.
rgds, sreten.
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Patent US5677957 - Audio circuit producing enhanced ambience - Google Patents
I built a prototype of this (see fig.2) for Alan that was shown at the '97 Comdex show.
I don't think Alan would mind you making one for personal use.
I used the 5532, others will be fine as well. 5% parts are adequate. The pot should be a ganged type, semi-log, or log type (audio taper) are fine, but a linear will do if that's all you can find.
I also came up with a very simplified non-adjustable version of this that was for stereo TVs and boom-boxes.
Alan is currently the chief designer at ORCA (Focal, Raven, etc), I am with Rockwell Collins.
This is a very natural sounding circuit, well worth the effort if listening to stereo program material.
I built a prototype of this (see fig.2) for Alan that was shown at the '97 Comdex show.
I don't think Alan would mind you making one for personal use.
I used the 5532, others will be fine as well. 5% parts are adequate. The pot should be a ganged type, semi-log, or log type (audio taper) are fine, but a linear will do if that's all you can find.
I also came up with a very simplified non-adjustable version of this that was for stereo TVs and boom-boxes.
Alan is currently the chief designer at ORCA (Focal, Raven, etc), I am with Rockwell Collins.
This is a very natural sounding circuit, well worth the effort if listening to stereo program material.
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Extend thanks to Alan. Any comments on performance? It looks like it could be fun to play with in certain apps... boomboxes and stereo movies and etc.
If you listen to Guitar Shop (Jeff Beck) it sounds like they processed it with this device with the level cranked way up (they probably used an Aphex unit).
It's completely adjustable from dry (off) to a very wet (fully processed) sound. If you have to place your speakers close together due to space limitations, you will really like this device. It has a very wide 'sweet spot' (unlike the Carver Hologram), and does not change the tonal balance.
This is really quite similar to the APT preamp, but has a small amount of frequency contouring for the remixed L-R signals to make it sound more natural (it does not sound 'phasey' in the HF like an Aphex or Barcus-Berry can).
One of Alan's newer designs:
http://www.stereophile.com/cas2010/raven_ebb_debut/index.html
It's completely adjustable from dry (off) to a very wet (fully processed) sound. If you have to place your speakers close together due to space limitations, you will really like this device. It has a very wide 'sweet spot' (unlike the Carver Hologram), and does not change the tonal balance.
This is really quite similar to the APT preamp, but has a small amount of frequency contouring for the remixed L-R signals to make it sound more natural (it does not sound 'phasey' in the HF like an Aphex or Barcus-Berry can).
One of Alan's newer designs:
http://www.stereophile.com/cas2010/raven_ebb_debut/index.html
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I found this older thread and thought I would post a 2015 update to it.
The Nuemann VAB-84 "vertical amplitude limiter" introduced around 1984 used a very clever width control circuit for vinyl cutting which is identical to, and predates and serves as prior art to, US5677957 by about 13 years. (Until I read this thread I was unaware of US5677957 which expired in 2009 due to non-payment of maintenance fees.)
While exploring the use of MS to provide vertical crossover aka "Elliptic Equalization" for vinyl mastering I stumbled upon the VAB-84 and its unique properties. One of those is the control of broadband or frequency-dependent width.
I first wrote about the VAB-84 here while experimenting with MS techniques and stumbled into the VAB-84 quite by accident: Pro Audio Design Forum • View topic - Using the Precision MS Matrix for Mono Crossover LF Blending
I then applied the VAB-84 to a purpose-built Width Controller: Pro Audio Design Forum • View topic - Stereo Width Control For Mastering Using the LR +/-S Method
This thread shows how to build one: Pro Audio Design Forum • View topic - Stereo Width Controller Construction Information
Designed for mastering and studio pre-mastering the circuitry has fully-balanced I/O. The actual Width controller is quite simple and uses a single gang linear taper pot.
There are a lot of variable width circuits posted - I thought I'd throw this one into the mix.
Wayne
The Nuemann VAB-84 "vertical amplitude limiter" introduced around 1984 used a very clever width control circuit for vinyl cutting which is identical to, and predates and serves as prior art to, US5677957 by about 13 years. (Until I read this thread I was unaware of US5677957 which expired in 2009 due to non-payment of maintenance fees.)
While exploring the use of MS to provide vertical crossover aka "Elliptic Equalization" for vinyl mastering I stumbled upon the VAB-84 and its unique properties. One of those is the control of broadband or frequency-dependent width.
I first wrote about the VAB-84 here while experimenting with MS techniques and stumbled into the VAB-84 quite by accident: Pro Audio Design Forum • View topic - Using the Precision MS Matrix for Mono Crossover LF Blending
I then applied the VAB-84 to a purpose-built Width Controller: Pro Audio Design Forum • View topic - Stereo Width Control For Mastering Using the LR +/-S Method
This thread shows how to build one: Pro Audio Design Forum • View topic - Stereo Width Controller Construction Information
Designed for mastering and studio pre-mastering the circuitry has fully-balanced I/O. The actual Width controller is quite simple and uses a single gang linear taper pot.
There are a lot of variable width circuits posted - I thought I'd throw this one into the mix.
Wayne
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