Heyaz! I've had my 950 for 5 days & I'm still experimenting with diff settings. My old receiver was a Pioneer Elite VSX-41 (basically an 811s)
as a Preamp with an ATI 1506 amp. On the old receiver, I left the tone controls flat & used either loudness or "midnight" mode for warmth. My speakers are Klipsch RF3,RC3 and RB3 (bright by nature) with Polk in ceilings as the rear surrounds. I'm using my ears & failing memory to compare. I was receiverless for 2 weeks prior to getting the 950. Anyhoo, while I'm not absolutely certain, it seems like I was getting more volume from the Pioneer. I don't listen to music/movies at ear bleeding levels regularly, just for tweaking, testing and occasionally jamming. What's a good MAX setting for volume? For most sources, I can't seem to get past -04 to -00 without sending the ATI amp into the red zone even though my ears could probably handle more.

TIA

Jeff

The first thing you should do is calibrate the 950's trims by use of the internal noise generator, and a RadioShack analog sound level meter. You should calibrate with the main volume at "00" and set the trims so that the reading on the sound level meter is 75db for all speakers, with the meter's weighting at "C" and the response set to "slow". Using these settings, the volume at "00" will yield the same volume that they mixed the movie at when watching DVDs, and pretty darn loud at that setting when playing CDs.

SH, having calibrated exactly as the manual and you described above brings up a question I'd been meaning to ask.
My Subwoofer is a passive 4 ohm 12" driven by a bridged Adcom 555II. This amp is rated at 200 Watts p/ch into 8 ohms. Now I cannot find the manual to give exact figures but you can figure this sub should be getting gobs of power right ! I figured the amp may very well complain about this load, even though it is claimed to be stable into 1 ohm. It is not distressed at all ! Hell it doesn't even get warm, which makes me wonder if the thing is working correctly in bridged mode. It is designed to be switched from Stereo to mono and 2 channel to single if one so desires. I used it for years without fault in stereo mode.
My question is this ... Why do I have to completely max out the gain within the 950's speaker setup for the LFE, and almost max out the gain on the ICBM also, to get the same db reading as all my other speakers ?
I would have thought this sub setup would have had to be tuned below the others by a considerable amount, so I'm missing something here !
Perhaps the 950's test signal is not optimized for subwoofer response (ie. too high in frequency) I think I'll draw up a response graph using a test disc. Could be a 20-25 hz signal might move my walls and otherwise detract greatly from the spousal acceptance factor that is already teetering somewhat !


[This message has been edited by Kiwi (edited February 06, 2003).]

Kwi

In bridged mode, you should not attach a load lower than 8 ohms. I would check your manual for the amp to see if they have any other specifics.

I just set the subwoofer by ear most of the time. I have a spectrum analyzer but when tuned for flat, the subs aren't loud enough for my tastes. You should have no trouble getting sufficient volume out of your sub. Maybe the power amp is going into protection mode with the 4 ohms in bridged mode.

Kiwi, I agree with Soundhound. Even though the manual for the 555II says you can use it in bridged mode to drive 8-ohm and 4-ohm speakers, any speaker that drops "substantially" below 4-ohms is not recommended. By the way, the manual says "...when any amplifier is operated in bridged mode, the load is split between the two amplifiers in the bridged configuration. Therefore an 8-ohm loudspeaker will be seen by the amp as if it were a 4-ohm load; a 4-ohm load will be seen as a 2-ohm load." Best wishes.
edited= you only have one sub and amp right?

[This message has been edited by steves (edited February 07, 2003).]

Well guys,I just got home from the hospital were they perform back surgery on me,so I might be still high from the drugs,but my Adcom 555 is rated at 850 watts at 4 ohms continuous,I am using it to power a SVS 25-31CS PLUS tune to 20hz,I have it calibrated at aproximatelly +3db's hot and I have never had any problems with my amp.I may some times bottom out my subwoofer,but my 555 never clipps in bridge mode;and I am playing at almost Dolby Digital reference levels (which are -2 db's under reference)Also when I bridge my amp my gain seems to incres by 3 to 4 db's.Just my two centes. J.R.

J.R.-- Good info! The 555 is a beast! I have a 555II which I use to drive my subs- but have wondered about how it would perform in bridged mode driving one of the SVS subs- if I were to get one. I hope your back surgery works out for you, and you re-coop soon. Best wishes!

I realize a bridged amp sees half the impedance supplied to it, and at the same time realize I am probably stretching the amps limitations, but figured the worst that could happen is to pop a rail fuse. The Adcom 555II amplifier has been used to do the very thing I'm asking of it. Manual also says a load no lower than 4 ohms should be applied in bridge mode. Personally I think my amp is having a problem internally combining the output of the 2 channels. Time for some testing.

The way the bridging works is that one channel is inverted in polarity at the input of one channel of the amp, and the other channel remains as before, then these are sent to their respective power sections. That way one channel of the amp is "going positive" as the other channel is "going negative". By connecting the speaker to the two "hot" terminals, the effective voltage delivered is doubled, which equals an increase in power in watts by a factor of 4.

By constructing a simple polarity inverting stage, almost any two identical amplifiers can be bridged in this manner, such as two of the 200s (although Outlaw would shoot me for suggesting such a thing )



[This message has been edited by soundhound (edited February 07, 2003).]

Wow, you are too much SH !
I've since found my manual and apparently I should get around 850 Watts bridged into a 4ohm load. The GFA555II is stable into 1ohm if the manual is to be believed. This amp worked perfectly in stereo with each channel driving 4ohms, so any ideas as to why my output is so low. Amp has front mounted thermal and distortion alert bezels which in the past seldom ever flashed, and do not at all now.
With the 950's gain on max and the ICBM (placed between 950 & 755) also on max, I'm getting 75db 1 meter from the sub, using the 950's test tone and volume set at 00. My gains for the 5 speakers on the 755 are in the negatives to get 75db @ volume 00 at the central listening position.
Somethings askew yes?