slow VU meters on Sony STR-V6

[ESM]

bottom line...

Sony STR-V6 (prepping for resale)
everything works perfect, perhaps i am just over reacting but the meters are almost dead..
unlike a sansui 9090db i had at one point, those meters danced all over..
there is a power button for the meters that i shot some deoxit in. (perhaps not enough?)

when powered on, they do not move at all
when powered off they barley move at all
same response with Aux, TT, and Tuner

i do have them hooked up to a pair of Canton Karat 100's which are 8ohm, 50 watt nom, 80 watt max
not sure if that would matter, just trying to cover my bases

Any help would be greatly appreciated, thanks

[papabearjew]

@ESM  I did a quick check on my Phase Linear 400 amp.  It has huge VU meters.  When powered up they do nothing.  When powered down they deflect just a few millimeters. Also bear in mind depending on the calibration of the meters and whether they are true VU meters vs. RMS or peak power meters they might not deflect till cranked up quite a bit.  My Phase Linear has VU meters and there is no switchable range so unless it's cranked up quite loud they barely move.  My separate power meter has two selectable ranges 0-2 and 0-200 watts.  It has analog RMS meters with LED peak indicators.  Set at 0-2 watts it is quite active.  Set at 0-200 watts it's pretty inactive (unless nobody is home)!  I don't know if this helps or not but I'd be happy to try and help more if I can.  If you want me to do specific test with my stuff seeing what the meters do just let me know.  Happy to help

[MacGeek]

The early MAC meters displayed db (voltage) and had a switchable scale (0, -10 and -20 db).  The newer amps display wattage, but also show a db scale.  With over 60 db of range, the meters are almost always moving.  For a short time, they made amps with switchable wattage and db circuits driving the meters.  Those models are very cool (Mc 2155 and Mc 2255), but don't have as much current capability as todays modern circuit designs.  The switchable circuits also added considerably to the price with out adding to sound quality or power.

PBJ-how accurate have you found the rat shack meters to be?  I had one of those once and found it a pain to have to get up and switch the range when I change volume significantly.

[papabearjew]

Hey MacGeek,
I believe the power meters to be fairly accurate.  I had it tested/calibrated a number of years ago and it seems OK.  I really don't care that much as it's more for entertainment value having something to watch.  Without question the average person would be amazed how little wattage they're using with a still fairly loud value.  Maybe 2 watts or so.  I'm being left alone for a bit this evening so I'm going to play some loud symphonies and see what the wattage shows with a sound level reading of about 100 db(c) from my recliner.  The range on the VU meters on the Phase Linear 400 is from -20 to +3.  It also has a scale from 1 to 100 where as 100 corresponds to 0 VU.  Not really sure what it indicates.  Maybe a percentage.  It's not wattage as the amp puts out 200wpc RMS. My son's Carver M500 has much more functional meters.  Much wider scale.  Of course it is a much newer design also

[papabearjew]

I just did some quick very unscientific testing for some quick readings.
Playing jazz at about 100 dB(c) from my seated position the power meter was hovering around 50 watts RMS with peaks flickering around 100 and occasionally 200.  The VU meter on my Phase Linear 400 was very active hovering mostly around -3 and frequently peaking at 0 VU with rare peaks at +1 and +2.  Playing a full symphonic piece at the same 100 db(c) everything stated above as far as readings were slightly higher.
Again this was unscientific as I didn't use a variety of musical pieces.  I guess I could do the test using pink noise which should give more accurate and repeatable readings.  That might be interesting.  I'll have to wear my shooting ear muffs though.
I'd be interested in any comments about this.  If you think I just rambled incoherently and am a total moron, and you're now dumber for having read it, I could easily live without your comments unless they're funny

[MacGeek]

FM interstation noise (which is close to white noise-less bass than pink noise, but usable for a test) might be a quick way to test the meters, without setting up a full blown pink noise test.  What the meters indicate will depend on what the circuit was designed to do.  The old MACs were designed to indicate rated power at +3db (or 1/2 power at 0db).

I do agree with your comment that the meters are mostly for entertainment value (I love watching mine in the dark).  If the music doesn't mesmerize me, the meters do.  However, knowing how they are intended to operate can make them useful tools for setting balance, measuring frequency response, etc.

[papabearjew]

I have a Stereophile Test CD that in addition to a dozen test 1/3 octave warble tones from 20Hz to 1kHz for testing speakers and rooms and other cool stuff, includes 2:15 (time) of pink noise. I find this really valuable for comparing source to monitoring on tape decks.  I tried to attach photos of it but the server said my files were too big and I don't know how to change them.

[MacGeek]

I don't have the Stereophile disc, does it have any other useful signals?  I do have a Sheffield A2TB test disc, as well as MoFi "Sound Check" disc and a Denon "Audio Technical" CD.  I think they all have some version of 1/3 octave and broad band pink noise as well as more, other test signals than any ordinary person might ever use.  When I have time, I prefer to set up the RANE (pink noise, calibrated mike, RTA, etc.), but usually don't get that involved unless I want to tinker with the EQ.  I do like some of the sweep tones on the test CDs to check speakers (and my room) for cabinet vibrations and resonance (found a loose screw that way once and not the one in my head:).

Maybe we should make copies for each other (and others?).  There is at least one unique test on each of the discs I have.  I also have test LPs to set up phono carts, a CD with reference tones to set up tape recording and who knows what else.

[papabearjew]

other than what I've already posted it does have a channel phasing track and 14 various symphonies suitable for some listening tests.  I can email you the back of it listing what's on it if you want.  I don't know how to copy stuff but when BJ is back when he has time maybe he'll do it. 

[MacGeek]

No hurry, no worries.  I'll try to learn how to copy what I have as well.  I always have trouble with file size when trying to post pics.  Resolution is another possible problem.  there is always the old photo copy and US mail.

[papabearjew]

BJ knows how to do all that.  If he has time I'm sure he'll help me.  He even gives me a family discount

[ESM]

Wow, thanks for the input, so in regards to the statments and questions raised hopefully i can clear up a few points.

1. The L/R meters are labeled "watts @ 8 ohms", the scale is 0,.03,.1, 1, 3, 10, 30 100, and 200 (which is funny because the amp is only rated to 115w)

 the right meter is also labeled "signal" (kinda cool, it doubles as a FM signal strength indicator)

2. there is a power switch on the far right labeled "Meter (above), Power/signal"(below).
 When this is pressed the left meter switches off and the right meter's primary function is signal strength. When wdve is dialed in (strongest station i can get) the meter moves into the 3 position (the scale being 1-5)

3. with the speaker selector switch in the off position, i turn the volume all the way up and still get very little movement,  .03 to be exact.

can these be out of calibration?
perhaps just stiff ?
maybe stretched out ?
i know im reaching but i just want to see them dance before i sell it..

Thanks again for the great responses and all of your assistance.

[MacGeek]

Are the speakers playing when the volume is all the way up?  I assume there is an input signal of some sort.  Some meters may not show power levels if there is no draw on the amp, even with the volume up (if the speakers are playing at full tilt, your ears must be bleeding:)

What happens with headphones?

Even a 115w amp can have peaks well past the rating, especially on very dynamic sources. 200w peaks are possible, but they should be brief.

If the right channel meter works as a signal strength indicator, it seems it should be OK.

[ESM]

The speakers are playing extremely well with the volume in the 1.5 to 3 mark on the dial. (proper listening levels, not blaring)
as far as input, Tuner, Aux, and record have all been tested successfully.
just tried my headphones, same deal, even tried headphones + speakers.
tried both A and B speaker inputs, but not combined.. yet...
with the speakers in the off position there is the same amount of movement as with them hooked up.
i am not registering past 10 watts, but i assure you.. it has exceeded that..
these pesky meters... i checked the circuit, all looks well, tapped, poked, prodded, you know, all the real scientific stuff.
perhaps its time to hook up the Jubal's... they can take the beating better than the Canton's..
let the experimentation continue.
any further thoughts and or suggestions would be great

thanks all