my denon wont play my sub, advice please

no it's not firmware.

how many speakers do you have? it sounds like you are running a 2.1 setup, correct (FL/FR/SW)?

let's go with the basics: what source are you using? what surround mode are you using? how is everything connected, etc.

so the subwoofer is not playing when receiving a multichannel signal (like Dolby Digital) over HDMI? even on a movie with DD or DTS 5.1? or is it only with 2-channel sources?

that's bizarre. I suggest trying a microprocessor reset, and then reset the speaker settings (Sub = "YES" in MANUAL SETUP > SPEAKER SETUP) and try again.

check the manual, it's in the table of contents in "Other Operations and Functions"

it's possibly a defective receiver. can you return it and exchange for a different unit?

wait, are your front speakers set to "large"?

no, not really. it's not exactly obvious.

the "large" vs "small" setting is not about the physical size of the speakers, it's about telling the receiver whether you want it to perform "bass management" or not.

if a speaker is set as "small", all bass below the designated crossover frequency will be sent to the sub.

if a speaker is set to "large", you are telling the receiver that it can handle the full range and so nothing will be sent to the sub except for dedicated LFE content.

So when the sub was set to "LFE" and the speakers were set to "large", the sub wasn't reproducing anything because the main speakers were getting full range. I bet if you put in a movie with a solid LFE track (like an action movie with explosions) the sub would have kicked in. But with, say, 2-channel music, there is no LFE track so there is nothing for the sub to produce.

When you set it to "LFE+MAIN", this is effectively a "double bass" setting, so the sub will double up the bass from the "large" main speakers. So, now you hear the sub on everything because it's "doubling up" the bass below the crossover point.

In general, for home theatre multichannel content, you want all speakers set to "small" so the sub can be dedicated to the low freq's.

Have you tried running Audyssey? You should go through that and see what it measures for your speakers, they may be better served set to "small".

Now this raises an interesting question. If the speakers are set to 'large' or 'full range', there is no crossover point. So when you use the 'LFE+Main' or 'Double Bass', which frequencies from the front L/R are sent to the subwoofer? It can't be below the crossover point, because there isn't one. Curious, isn't it?

if the speakers are SMALL it doesn't matter what the LFE setting is, it's only relevant for speakers set to LARGE.

it's hard to say what the xover should be, totally depends on your speakers/room. Even if you haven't added surrounds yet, go ahead and run Audyssey and see what it measures your speakers at. I think you will definitely hear an improvement in the Sub because not only will the fronts not be trying to double up the bass, but Audyssey EQ's the subwoofer.

Yes set all speakers to small and sub to yes and LFE only. Start by setting your crossover at 80Hz for all speakers. I would also recommend running Audyssey with only the speakers you have since it measures and sets speaker distances and equalizer settings. Just re-run it after you get your new surrounds in place. Be aware, that Audyssey will likely set your speakers as "large" or "full-range", and you will have to manually change them after running it.

You still set a crossover frequency in the menus, it just acts as the "double bass" point for speakers set to large. You are correct in that technically it's no longer a "crossover" at that point, but Denon won't win any awards for the internal logical consistency of their menus and manuals.

For example, if you have your Front L/R set to "LARGE" and the crossover set to "80Hz" for the fronts, it will just double up the bass below 80Hz for subs + mains.

Wait a moment. So Denon has you set a crossover point independently from selecting 'Large' or 'Small'? That is just bizarre! I was going to ask what happens of you set all speakers to large and use LFE+Main, but if it's still asking for a crossover point regardless of bass management, I guess that explains it, and it sort of makes sense. It doesn't explain what happens in my Onkyo, but that's another thread.

It's not that bizarre when you consider that you need some way to "tell" the receiver where to stop sending bass to the sub when using the "double bass" setting of LFE+MAIN. If you just understand that for "small" speakers it's the crossover point, and for "large" speakers it's the "double bass" upper limit, it sort of makes sense.

Gotta be your settings man.. Is it doing DD?

a little late to the party? the problem has already been solved