GRAPH: pioneer preamp voltage at every volume settings, 50Hz @ 0 dB and -3 dB,

[frankiebones 10+ year member]

I tried to make a graph but couldnt upload it, regardless the chart is uploaded. i wasnt expecting anywhere close to 5 but i certainly wasnt expecting under 1 V for almost the entire vol band.

I did not have the time to get each readings with processors and EQs in the mix but I did a few that were a lot higher using the 50Hz test tone (0 dB). I will do the rest later today.

I had the leads of my DMM directly touching the RCA connector. I made it easier on myself by wrapping Velcro ‘tape’ around my arm rest in my car to keep the RCA cable stable so I could, uh, y’know, probe it for lack of a better word. I ended up being able to tuck both the (+) and the (-) leads of my DMM under the Velcro so that they were making very solid connections to the RCAs without me doing much to hold them there.

Sure enough, after I had turned the volume all the way up and logged each value, I slowly turned it down and on the DMM confirmed each voltage to the third decimal in many cases. then when I was forced to switch from a 2V range to a 20V range, I checked for a 3rd time to make sure that the values would be the same. My DMM at both ranges used is accurate +/- .5%, so unfortunately for me (I’ve been listening to my system with only .262 V preampwhen messing wityh my EQs) and maybe also for you if u are reading this, these pioneers don’t go close to the ~2.5 volts you would assume they actually get if they advertise they get 5V. also, here is a graph, I will also be doing a logarithmic analysis to determine clipping later on in the day (thanks thcn).

P.S. The sound processing I was using to get the values in the right column are as follows:

BBE - +2

BMX +1

Also, I was boosting both my 31.5 and 50 Hz EQ bands +2 dB, which from what I know is gonna ask the amp (and I guess the HU also) for a lot more power

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[nauc 10+ year member]

too tiny, cant see anything

 

[LinxuS 10+ year member]

How long did this take you? I'd like to do it to find out where my volume clips, and also to maybe do as a report for extra credit for my stats class.. lol

Btw.. can't see the graph at all //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif.

 

[mannyb18b]

can't see the graph. Make it larger and what model H/U do you have?

 

[theCybe 5,000+ posts]

HU: Pioneer DEH-P7800MP

3char

 

[Flipx99 5,000+ posts]

hmmm....

to test, you put both pos and neg leads to RCA jack or what? Pic of how this should be done.

I wonder if the test would be different if you tested closer to the amp?