Explanation on the Denon 3802/3803/480......

A friend of mine just bought the Denon 3802 (demo leftover for decent price).
We were talking about its surround setup and he was adamant that he could have 9 powered speakers with this receiver. Needless to say for a mere $1300 Cdn i was a bit shocked that this was true. I took a look at the manual and the surround back/multizone thing is a bit under-explained.

Do these Denon receivers actually power 9 speakers? (I know my Onkyo 797-6.1 capable has a multizone as well but the 2 extra speaker channels require a separate amp).

Can you really use the surround A & B channels on these Denons at the same time in conjunction with the surround back/multizone channels?

If so, then essentially those Denon receivers should be touted as 9.1 capable no?
Why would anyone ever consider another receiver at the same price point over the Denons (unless they had a similar option)?

I simply do not remember seeing, reading or hearing about this feature on the Denon receivers when i was glossing over specs last year.
I'm not all too sure if i should be peeved or not.

From the description on Denon's website:

"Power Amplifier Assign function, lets you assign 2 of the 7 amp channels to drive second zone speakers directly"

Yer buddy is wrong. Yes, he can have 9 powered speakers with this receiver, if he has an extra 2 channel power amp laying around.

Right. The receiver has only 7 units of power amp.

In reply to:
"Power Amplifier Assign function, lets you assign 2 of the 7 amp channels to drive second zone speakers directly"

This statement is correct but can be interpreted differently.
It can also say that 2 of the 7 channels can be made into a second zone speaker, but according to the manual, i'm not 100% sure that they could also be used as the 8th and 9th surround channel in the rear.

Here is a pic of the back of the Denon. You can clearly see the hookups for pre-outs AND what looks like 9 speakers. That multizone can be set to either surr back or zone2 and the A&B surrounds can be used independantly or together.

So again i query, can these Denons really power and play 9 speakers in a complete surround setup? (if zone2 was set to surr back in the Denon options)

hmm. Interesting. I didn't see a pic of the back. That looks like a really, really weird setup to me. I mean, what's the diff between Surround A, B and Back?

In reply to:
I mean, what's the diff between Surround A, B and Back?

This is what i can't understand.
The A & B surrounds appear to be regular, exact type surrounds (would play the same surround sounds but nonetheless, out of 2 channels for the sides, not just one) while the surr back/multi channel is used for either surr back as normal or the second zone.
Yet if you have TWO channels for surr A AND B and they can be used independantly, OR as the manual states "A+B", then what the heck?
That is 9 speakers powered on a $2000Cdn (or less) receiver.
I paid a similar price for my Onkyo which is limited to 6 channels with 2 more pre-outs for a zone2 but requiring a second amp.
I simply could not believe what i saw when i looked closer at this Denon setup.

Am i missing something here?

So again I respond:

NOPE. Only 7 amps inside, period.

So what are the extra speaker terminals??

Ok, so if there are only 7 amps inside (confirmed by the specs on the receiver and sushi's good word of course), then how can you run both the A & B channels while using the surr back option?

Here is a link to the 3802 manual. See pages 10 and 11.
It shows back surrounds in use with both the A & B surrounds although A&B are not on at the same time. Yet in the options (page 11 top right), you can set which DSP will turn the A & B channels on at the same time.

sushi,
Are you implying that somehow one or two (or all three) of these surround channels are connected to only 2 amps internally such that only 2 of the channels will ever play at one time?
(A + back, or B + back or A+B but not A+B+back?)
Or that even all 3 channels will play at the same time but one channel would be drawing a doubly heavy load?

If so, then the manual is extremely confusing on this point.
Obviously since i do not own the receiver myself i cannot just hook up 9 speakers to test out how this works.

Chess, the first point is that a single amp could theoretically drive dozens of speakers if they were connected in a series and parallel combination so as to keep the overall impedance within normal limits. In the case of the 3802 the two side surround amps can each drive two surround speakers simultaneously when A + B is set because those speakers are driven in parallel(e.g. if they're 8 ohms the resulting impedance is 4 ohms). So certainly, 9 speakers can be powered, but this isn't anything unusual. Even a 7 channel receiver which doesn't have the A and B side surround terminals can be hooked up to 4 side surround speakers with the appropriate wiring scheme. Of course, the receiver in that case wouldn't have an internal provision for selecting A, B or A + B.

So basically the second possibility i mentioned is what is happening.
The Denon folk are allowing users to run both surrounds off a single amp channel but there is inherent danger in doing this.
As you mention John, running the second set of speakers off this channel will lower the impedance by half which is really going to work the receiver pretty hard. If anyone did not keep to the strict spec of using only 8 ohm speakers in these surround positions, they may begin wondering why the receiver keeps shutting itself down.
Has anyone tried this full 9 speaker config with the QS8s or any other 6 ohm speakers?

The extra surrounds are to allow for multiple setups. DVD-A is encoded with surrounds in the back corner opposite the fronts. Movies, are engineered to make use of speakers to your side and maybe one or two to the rear but center. This allows you to toggle back and forth depending on what you're listening to.

Semi,
I understand that this was the design of the A & B surround options on the Denon receiver but what i could not understand is why they had also included the option to run all at once.
It essentially is hooking up the surround channels in parallel as JohnK mentioned and in my mind, this is really not a recommended option unless the amp is capable of living up the to the task.
It never occurred to me that the Denon engineers had so much faith in their product but now i'm truly impressed.
Still, limiting those two surround speakers to 8 ohm i would think is a strict necessity if they are going to be used simultaneously..

Belatedly...

I've heard that Denon's receiver manuals are badly written. But I am impressed on how confusingly it is presented indeed. The Pioneer manual is better in comparison, although I wouldn't say it is well written, either. No wonder there are very few Japanese universities that provide any formal courses in technical writing.

In reply to:
No wonder there are very few Japanese universities that provide any formal courses in technical writing.

Well sushi, perhaps if there are equally few universities in the States that have Japanese technical writing that US made manuals for Japanese electronics sales are also being cursed for their horrible language conversion.