[sdiy] LM13700 crossfade query

Ian Fritz ijfritz at comcast.net
Wed Jun 15 15:35:02 CEST 2011

At 05:47 AM 6/15/2011, Tom Bugs wrote:
>What I'm wondering is whether the summing sketch with the outputs summed 
>as drawn is a good way or a total idiotic no-no.

It's the best way to do it. Works just fine. An example here:


>  In which case I'd have to do two TL07X buffer stages (one for each half 
> of the lm13700) and then have another summing stage.
>I'm sure there was a project that did similar but I can't track anything 
>down now. The nearest I've found is the Crumar BIT1 which sums the pins of 
>multiple LM13700 outputs together and then buffers in a similar way to my 
>drawing but with one slight difference - there's now an input resistor 
>before the TL07X (ie. after summing the LM13700 outputs).
>Thanks for any pointers here!
>BugBrand LTD
>UK company No. 07199808
>VAT No. GB 988 2629 57
>1 Ninetree Hill
>United Kingdom
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