I have added VU-like meters to my tube pre-amp output, just to have a nice visualisation of loudness. I have used this driver board and meters 2pcs Analog VU Meter Panel Kit Backlit Decibel/Level Tester with VU Driver Board 782429278986 | eBay. The preamp is an aikido design with 6cg7, so it has a Zo for the 6cg7 700ohm and of course, is capacitor coupled to the next stages. Assuming that the driver board of the VU meters is a buffer with quite high input impedance there should not be a problem ton parallelize it with my power amps (push-pull KT88 with 100k input impedance).
But is this really the case? Has anyone used any of these on the OUTPUT of a tube preamp (I want it to change with volume control)?
Has anyone any idea on the input impedance of these or similar driver boards? For example, I might need to change coupling capacitors in order to lower the corner frequency of the high pass filter. Any info would be highly appreciated 🙂
But is this really the case? Has anyone used any of these on the OUTPUT of a tube preamp (I want it to change with volume control)?
Has anyone any idea on the input impedance of these or similar driver boards? For example, I might need to change coupling capacitors in order to lower the corner frequency of the high pass filter. Any info would be highly appreciated 🙂
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