Anyone have 'stereo blend' control experience?


I'm interested in any details anyone may be able to provide concerning 'stereo blend' controls, for progressivly reducing a 2-channel signal down from full separation towards a mono blend, presumably through cross-mixing.

What older equipment might you be familiar with that featured such a contol? Did any incorporate a 'defeat' provision, or was the control always in the circuit? If you ever used one, how well do you remember it working?

Do you have any electrical design knowledge of previous implementations of this idea, or suggestions on how to make one? What kinds of parts were used in any older designs you may have seen? Do you know of any schematics?

I realize this probably was a pretty obscure feature even in its day, but maybe some of you more, ahem, experienced hands out there know what it is I'm talking about. TIA for any info!
zaikesman
The Apt Holman preamp (great 70s gear available on Ebay)has the best stereo blend control I have seen. Complete infinity variable blend/separation of channels. A real eye opener.
Adding to the above.The HK Citation I and IV.Both have a varible blend control.It also controls a center channel speaker if you want.Out of the circuit when not in use.I would also reccomend the IV over the I for a very open smooth sound.The I sounds a bit restricted/compressed.IV has much simpler circuit.They also have a switch to take tone controls out of the circuit.Mono,Chan A and B.Reverse switch also.The IV is a very cool Preamp and has a classic look.Uses 6 12AX7's.
The Crown IC-150 was a top rated pre-amp back in the early 70s. It has a stereo blend control. I had one back then and found the blend control very useful--more blend for small groups or solo performers, less for big orchestras.
I wonder why this feature has disappeared today?
Craig Zastera
CraigZ I completely forgot about the Crown IC150 & yes that was a real nice preamp back in the day. I've even seen one up for sale here not very long ago. Zaik I think you'd like that one.