Meter Buffer Placement and Options

[buildafriend]

Hey guys,

I'm toying around with a tube circuit where the VU meter taps right off of the primary high winding of the output transformer at an unbalanced point. Beyond this stage I have implemented a post transformer line pad on a switch for -18dBu.  I want to move the VU meter to read from post the output pad network which is balanced and I'm considering designing a little board for a TL071 meter driver buffer.. I was curious if anyone knew any easier ways to have an analog VU meter read from a balanced line level signal.

Thanks, 

 

[rackmonkey]

I figured someone smart would have offered a clever alternative, but in the absence of that I'll just reincforce that your proposed TL071 based circuit (using both the inverting and non-inverting inputs for balanced signal) is very simple and exactly what I used to do what you want to do here.  I think you get more a little complicated using discrete transistors. I'd go with what you propose. FWIW. Good luck.

BT

 

[ruffrecords]

JLM audio has a handy kit for this:


https://www.jlmaudio.com/shop/vu-buffer-peak-led-kit.html

Cheers

Ian

 

[abbey road d enfer]

Just beware that you're dealing with quite high voltages there; the component values must be scaled to these voltages. Typically, the voltage at the primary is about 10-100Vrms.