Equipment ouput/input impedance and volts matching?
Equipment ouput/input impedance and volts matching?
Author
Discussion

paul.deitch

Original Poster:

2,211 posts

273 months

Sunday 25th April 2021
quotequote all
I have an old preamp with a spec RCA output of 200mV / 2.2K-Omh.
I have the possibility of being obtaining for a good price an amp with a spec RCA input spec of -10dBV.

Will it blow up? Will it be ultra quiet and noisy? I have no idea. May be someone here can advise.

Lucid_AV

452 posts

52 months

Sunday 25th April 2021
quotequote all
-10dBV is the equivalent of 316mV. That means if your pre-amp has a maximum signal level output of 200mV then it's still below the the power amp's maximum threshold. Nothing is going to blow up.

paul.deitch

Original Poster:

2,211 posts

273 months

Sunday 25th April 2021
quotequote all
Cool. Thanks very much for the reassurance. I'll buy it then. smile

jet_noise

5,917 posts

198 months

Sunday 25th April 2021
quotequote all
Short answer yes, probably, might be a smidge quiet. Crackie is the audio gnu wink if he pops up he is better informed.

Long answer.

Is it definitely dBV not dBv?

Yes there is a difference.

Ass. 'tis V then -10dBV= 10^(-10/20) * 1= 316mV (equ'n explained here)
If v then it isn't as simple as replaceing the 1 with 0.775 and getting 245mV as the input impedance needs to be taken into account!
Also is there no input impedance specified for the amp?

ETA I see Lucid got there 1st smile

paul.deitch

Original Poster:

2,211 posts

273 months

Sunday 25th April 2021
quotequote all
A smidge too quiet shouldn't be a problem as I'll be moving from 30 wpc to 200. The existing floor stander speakers are rated at 80 wpc so I'm going to splash out on them as well as I haven't spent any real money on fun for a year now. The problem will be to find something that my wife likes the look of....