• QuadraphonicQuad welcomes you and encourages your participation! Treat all members with respect. Please keep all discussions civil, even when you have a strong opinion on a particular topic.

    Do not offer for free, offer for sale, offer for trade, or request copies or files of copyrighted material - no matter how rare or unavailable to the public they might be. We do not condone the illegal sharing of music. There are many places on the internet where you can participate in such transactions, but QuadraphonicQuad is not one of them. We are here to encourage and support new multichannel releases from those companies that still provide them and as such the distribution of illegal copies of recordings is counter-productive to that effort. Any posts of this sort will be deleted without notification.

    Please try to avoid discussions that pit one format against another. Hint for new users: make liberal use of the search facilities here at QuadraphonicQuad. Our message base is an incredibly rich resource of detailed information on virtually all topics pertaining to surround-sound. You will be surprised at what you can find with a little digging!

Smell of Smoke

Help Support QuadraphonicQuad:

par4ken

500 Club - QQ All-Star
Joined
May 28, 2011
Messages
583
Location
NW Ontario
You got me thinking about the + and - 15 Volt supply, I seem to recall at one time when I decided to replace the power supply filter capacitors, finding that the supply voltages were odd, possibly +17 and -13 so I tweaked the supply to give exactly 15 Volts on both rails. It did still seam to work properly after that though, but might have something to do with the incorrect soft clip circuit voltage, that I'm seeing.
Well I got looking at my unit the other day and found that there was a oscillation on the power to the soft clip circuit in addition to the voltages being off. I got around to undoing my old modification that changed the power supply voltage to +/- 15 Volts , setting it back at +17 and -13 Volts and that got the soft clip voltage closer to speck and eliminated the oscillation. The set of Blue print drawings of the S&IC that I have didn't show the modification. There still is something not quite right between center back and center front, but it is usable and still sounds good!
 

The Quadfather

Moderator
Since 2002/2003
Joined
Mar 7, 2002
Messages
1,534
Location
Dixie
Good for you, you get to enjoy your S&IC a little longer. I'm still waiting on my Soundmaster, but the manufacturer has the boards now. I guess it won't be long now. The one good thing about this is I will have a QS decoding capability I never had before.
The Quadfather
 

par4ken

500 Club - QQ All-Star
Joined
May 28, 2011
Messages
583
Location
NW Ontario
Originally with my S&IC I never bothered setting up the Axial Tilt (for several reasons) the main one being that the test tracks on the test LP's were far too short; by the time I got the record on and my screw driver ready the track was almost over. Today I recorded the test record to the hard drive, then in Addition copied the sections that I wanted and pasted them back into the audio file to make the test tracks longer. Then I played the recorded test track back through the S&IC and easily adjusted the Axial Tilt. I've now been dubbing my LP's using the S&IC to tilt process the signal and then have been testing out the recorded tracks by playing them back through my various SQ decoders and they all (without exception) decode much much better! Without the adjustment I would estimate the phono separation to be about 20dB, (what we used to consider to be perfect). I used a scope to aid in adjustment and was able to null out almost all of the cross-talk, the scope for me is far more accurate than adjusting by ear alone! So even with a B.O. S&IC you should keep it to use the Axial Tilt feature! I doesn't just improve front separation but separation across the back as well.
 

Lynn Olson

Active Member
Joined
Aug 29, 2010
Messages
83
Glad to see my little invention (axial tilt) is still working for you! A small part of Shadow Vector lives on!

In principle, with a little extra circuitry, it could be aligned with nothing more than a mono record, but the Shadow Vector project was long gone by then.
 
Group builder
Top