Setting volume levels on RSP-1098 - rears seem soft?

[jlee]

Hello. I just got my RSP-1098. Firmware is version 3.1 (I guess the 2 week wait was worth it... seems as if I ended up with the most recent version). I just got my Classe CAM-200 for the center channel yesterday.

Setup:
Left, Center, Right - CAM-200
Rear - RB-1080

The gain as tested by Stereophile is about 28.4 dB on the 1080... and about 29 dB on the CAM-200's. Therefore, I would expect little to no difference in setting up the volumes. I use to have an RSP-1066. The sensititives of my speakers are all rated at 89dB except the center, which is rated at 90dB. I have found that the fronts are probably a bit higher than 89dB and the center is probably a bit lower than 90dB... because if I reduce the center by 1dB, it sounds a bit softer and if I leave it as is, it's a bit louder... so I just leave it as is ... helps a bit with dialog so it's all good. As for the rears, I have found in the past I needed to boost it up 1dB to match it with the rest due to the drivers not pointing as DIRECTLY to me as the fronts.. so you get that natural 1-2dB rolloff as you go off axis... I actually had it set 2dB higher so it was a bit louder than the fronts by about 0.5dB (just a preference thing).

Ok, now with the 1098... I had to pump up the rears 7dB just to get them to match the center and mains... is something wrong? Even with the 1066 and CAM-200's as mains, I did not have to do this...

I looked at the sensitivities of the 2 amps... 1.5V for max output for the 1080... and 1.0 V for max output for the CAM-200... but I thought it was the gain spec that determined loudness?

To me, having to adjust more than 1-3 dB seems a bit odd.

Also, on the 1066, I use to use 67-70 (max reference level) volume for 2 ch listening, 68-70 for DTS, and 73-75 for Dolby Digital. For the 1098, I am finding I'm using 80 for DTS, 85 for Dolby Digital, and about 75 for 2 channel. Is this mostly due to the 1098 volume settings being configured a bit different than the 1066?

[Aussie Geoff]

jlee,

Something sounds very wrong. Have you calibrated with a sound pressure level meter and the test tones? Most people end up with a reference level of 71-77 on the RSP-1098 doing this. I would die if I listended too long at 80 or 85...

The gain issue between amps is another matter - the gain can be affected by the relative input impedences of the amps so it is possible that they are effecting it. For example I have the RM-1080 and RMB-1075 which also have similar gain spec but I find they are 5 DB different - wht the RMB-1075 being 5 db more gain than the 1080.

Also do you have all your speaker distances set...

Let us know how you go after trying all this

Geoff

[jlee]

1. I have calibrated with SPL and test tones.
2. I have a VERY HEAVILY damped room with lots of padding and curtains, etc... when somebody yells in the room, it sounds like normal talking. So I think the 80-85 is like 70-75 in another room.
3. So with the 1075, you have the 1080 +5dB compared to the 1075 right? That would be about the same situation as me... 1075 has 1V in for max output... 1080 has 1.5V in for max output... same ratio as CAM-200 to 1080... and I have it at 7dB compared to your 5dB... 1dB higher due to my own preference... and 1dB due to being slightly off axis... so your 5dB is like my 6dB... and then I add in 1dB as a choice.
4. Speakers distances all set... I have them all 8ft away... actually the rears are 7.5 ft, but I set it at 8ft initially...changed it to 7ft now. I had it at 0 delay in my old 1066 due to it either having 0 or 5ms only... with the 1098, I like the extra control of being able to set 1ms (about 1ft) changes.
5. Everything sounds great... just seems odd I would need 7dB compensation.

[jlee]

"Ok, now with the 1098... I had to pump up the rears 7dB just to get them to match the center and mains... is something wrong? Even with the 1066 and CAM-200's as mains, I did not have to do this..."

I said this in an earlier post... I stand corrected... I don't specifically recall actually checking this as I did not have the 1066 very long with CAM-200's as mains... it may very well have required pumping up the rears 7dB, even with the RSP-1066.

As for the volumes of 75 for 2 ch, 80 for DTS, and 85 for DD... I find that I can listen louder with the 1098 due to less high freq. distortion than the 1066... those settings are actually pretty loud... it's more like 74-75 for 2 ch, around 78-79 for DTS, and 82-83 for DD...

So everything seems to be ok with my 1098... sound is excellent... but if somebody can explain the 7dB difference, it would satisfy my curiosity. See below:

I checked the specs on the 1080:
1.5V, 32 kOhms

CAM-200
1.0V, 75 kOhms

If somebody can explain how the different input impedance affects the necessary settings, I would be grateful. Thanks again!