Rotel RSX965 5.1ch input mode LFE problem

[craby]

Hello,

I have a Rotel RSX 965, which has been serving me quite nicely for about the last 12 years. I decided to put some more life into it, so I bought an Oppo BDP 83. The oppo is connected to the rotel by an analog to DB25 cable, and I use the 5.1ch input mode to effectively just make the rotel an amplifier so the oppo does all the decoding work.

Anyway, it works perfectly, and I now get True HD and DTS Master (albeit 5.1 versions of it). SACD and DVD Audio are just superb. But, I'm having a big problem with a really low LFE volume.

When I have it running on 5.1ch input, there's bass from the sub, but almost no LFE i.e. very deep rumbling bass. If I swap over to the optical link, and let the rotel do the decoding, there's plenty of LFE.

Oppo suggested that I just increase the volume on the sub itself, or in the rotel. I can also increase it in the oppo as well.

I've done all of those things, and all it does is increase the bass from the sub, but there's no apparent LFE info in 5.1ch input mode.

I know about the -10db on analog issue, but turning up the sub (it's usually on about a 1/4 volume, or adding +10db in the Rotel isn't solving the issue. Wth this model, I can only adjust the sub output, not LFE.

I was wondering if anyone else has encountered this? I'm assuming it's an issue with the rotel in 5.1ch input mode, but I'm not 100% on that.

Any assistance would be greatly appreciated!

Thanks in advance.

regards,

craby

[srb]

My understanding is that the 5.1 DB25 input on the RSX-965 works the same as the 5.1 Multi RCA inputs on my RSX-1056, and is a strictly an analog input, bypassing all processing and bass management in the Rotel.

Changing the Rotel's LFE level will accomplish nothing for that 5.1 input. Although you say you have tried all adjustments, the only adjustment that makes any sense is increasing the LFE level in the Oppo.

In the Oppo Speaker Configuration menu, check that
- 5.1 Down Mix is selected
- Subwoofer is On
- Subwoofer Trim Level is all the way up (+10dB)

The LFE crossover for analog outputs in the Oppo is fixed at 80Hz, so check that
- Subwoofer output of the Rotel is connected to crossover bypass input on the sub or
- If there is no crossover bypass input, that the sub's crossover frequency control is set to the highest maxiumum frequency.

If you have tried or confirmed all of these settings, I'm not sure what else the problem might be.

Steve

[Nuthed]

My understanding is that the 5.1 DB25 input on the RSX-965 works the same as the 5.1 Multi RCA inputs on my RSX-1056, and is a strictly an analog input, bypassing all processing and bass management in the Rotel.

Changing the Rotel's LFE level will accomplish nothing for that 5.1 input. Although you say you have tried all adjustments, the only adjustment that makes any sense is increasing the LFE level in the Oppo.

In the Oppo Speaker Configuration menu, check that
- 5.1 Down Mix is selected
- Subwoofer is On
- Subwoofer Trim Level is all the way up (+10dB)

The LFE crossover for analog outputs in the Oppo is fixed at 80Hz, so check that
- Subwoofer output of the Rotel is connected to crossover bypass input on the sub or
- If there is no crossover bypass input, that the sub's crossover frequency control is set to the lowest minimum frequency.

If you have tried or confirmed all of these settings, I'm not sure what else the problem might be.

Steve

Why would you recommend setting the x-over frequency on the sub, if it has no dedicated LFE input, to it's lowest setting?

Setting it to the highest setting is what he needs to do. This removes it from the chain and lets the Oppo's x-over do the filtering.

[srb]

Why would you recommend setting the x-over frequency on the sub, if it has no dedicated LFE input, to it's lowest setting?

Because I made an error, and should have said highest crossover frequency setting.

Setting it to the highest setting is what he needs to do. This removes it from the chain and lets the Oppo's x-over do the filtering.

That's correct, thanks.


Steve

[Nuthed]

Because I made an error, and should have said highest crossover frequency setting.

Steve

I kinda thought so. :T

[n9949y]

A LFE volume control solution

I, too, have a Rotel RSX-965. With a custom built cable, RCA jacks one end plugged into a Blu-Ray Panasonic DMP_BD-55 analog audio outputs and pin jacks at the other end plugged into the Rotel SACD inputs, I get from the Blu-ray player lossless codecs DTS-HD Master Audio and Dolby TrueHD audio. Interesting that a receiver designed 12-13 years ago can still be used for an audio reproduction method un-anticipated then. Way cool, that Rotel.

In 1990 I bought a Yamaha A300 Digital sound Processor (couldn't part with) plugged into one of the Rotel's audio tape loops. The Yamaha Processor has a specified LFE RCA output to which I have 2 Yamaha YST-SW205 sub-woofers connected. [one located under the LG 44” monitor (DLP-still working after 5 yrs), the other at the opposite end of the living room]. So, I can easily set LFE volume using the Yamaha A-300 remote.

Incredible LFE control. When I recently played a Blu-ray DVD of U-571 (WW-II submarine story) which has cracking, house shaking surround depth charge sounds, the dual subs did one hell of a job- had a sofa lounging cat that disappeared for 2 days!