Probably a real dumb question......but here I go. I have one of those Gray Research 602C passive equalizers that were used mainly in broadcasting back in the day. The inputs accept 2 turntable sources.....the output is balanced or unbalanced 150 ohm.........They were made to go into a hi gain mic input on one of the old audio mixer boards.....I want to try this with a Stanton 310 B phono preamp........it is stereo with up to 60db gain.with NAB or Flat selector switch...The output is balanced or unbalanced......the stereo inputs are 47K...My idea is to use a splitter cable out of the Gray equalizer into the Stanton......150 ohm source into 47k ohm inputs.......................Is that Kosher, or do I need a method to change the input impedance??? Any ideas appreciated.
For voltage matching, the rule is low Z output into high Z input.
The input impedance should be at least 10 times greater than the source impedance.
The input impedance should be at least 10 times greater than the source impedance.
Impedance Question
Galu.............thank you........so you are saying that I should be ok with the 150 ohm source into the 47K ohm input??? jack
Galu.............thank you........so you are saying that I should be ok with the 150 ohm source into the 47K ohm input??? jack
To ensure that maximum signal voltage reaches the input - yes.
Even if you parallel the stereo inputs you will only half the 47k input impedance and will still be well within the parameters stated in my post.
Even if you parallel the stereo inputs you will only half the 47k input impedance and will still be well within the parameters stated in my post.
Galu.............thank you........so you are saying that I should be ok with the 150 ohm source into the 47K ohm input??? jack
A 150r output impedance into a 150R input impedance would lose half the signal.
Low output impedance into a high input impedance is best.
Nevermind the impedance.
The Gray 602C gives RIAA equalization. The Stanton 310B normally gives RIAA equalization. Putting them in cascade will give WAY TOO MUCH equalization. That's not how it works.
The Gray *MUST* go to a high gain FLAT amplifier.
The Gray is not too sensitive to load. It is however somewhat sensitive to phono cartridge parameters (see page 3). It is not likely to give correct EQ with any modern cartridge.
Ahhhh.... The Stanton 310 does have a flat setting. This is suitable. Try either stock 47k or with a 1k resistor tacked across the input (good approximation to a classic "for 150 Ohm" tube mike preamp).
https://www.surplussales.com/Gates-Harris/pdf/eqp-602-c.pdf
http://lcweb2.loc.gov/master/mbrs/r...Model 310 Prof. Stereo Phono Preamplifier.pdf
The Gray 602C gives RIAA equalization. The Stanton 310B normally gives RIAA equalization. Putting them in cascade will give WAY TOO MUCH equalization. That's not how it works.
The Gray *MUST* go to a high gain FLAT amplifier.
The Gray is not too sensitive to load. It is however somewhat sensitive to phono cartridge parameters (see page 3). It is not likely to give correct EQ with any modern cartridge.
Ahhhh.... The Stanton 310 does have a flat setting. This is suitable. Try either stock 47k or with a 1k resistor tacked across the input (good approximation to a classic "for 150 Ohm" tube mike preamp).
https://www.surplussales.com/Gates-Harris/pdf/eqp-602-c.pdf
http://lcweb2.loc.gov/master/mbrs/r...Model 310 Prof. Stereo Phono Preamplifier.pdf
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