[sublimation]

I'm looking to improve my HT setup and am thinking of adding a multi-channel Power Amp. Currently, I have a Denon 3808 driving B&W 683s in the front, 684's in the back, an HTM61 centre and a PV-1 SW.

I haven't seen an AVR above mine that I could justify the expense for, so I am thinking of breaking out the Amp function and keeping the 3808 for all the processing goodies. Does this make sense? Anyway...am thinking of adding something like a Rotel 1075 or an Emotiva XPA-5.

Any advice from the forum would be appreciated...critical as well;-). I still have a lot to learn...

Cheers,
Russell

[KelvinS1965]

I'm kind of in the process of doing this, but mainly to improve stereo music quality, as I'm fairly happy with the HT sound, using HD soundtracks. I recently did some listening tests using my 2808 as a preamp (in Pure direct mode), my Arcam P1000 power amp and Arcam P90/3 to run the front left and rights (all single wired, no biamping to confuse the issue just yet). Source was an older NAD C540 CD player as it sounds much better than my BluRay player for CDs.

I found that I didn't really hear much difference between the 2808 on it's own or with either Arcam power amp, so I tried another option: I have an older NAD C350 stereo intergrated amp with pre-power amp links on the back. I found that I prefered the NAD on it's own compared to the 2808 on it's own, but then I tried the NAD as a preamp only with the P1000 and the P90/3 and found there was a difference with this combo and the best seemed to be using the NAD as a pre amp, with the P90/3 for power amp duties, using the P1000 was not quite as good as the P90/3.

So my conclusion after all this swopping of amps and cables was that the 2808 isn't a good enough preamp (even in Pure direct mode) to get the best out of the better power amps. It works as a stepping stone to a further upgrade in that it helps share the load using the 2808 only for surround duties and the P90/3 for the front three speakers. However, the sound quality is only changed by a small amount IMHO. Longer term I would like a more 'musical' pre-pro or perhaps a better sounding receiver that could still use the P90/3 via pre outs to give me the stereo sound quality equal to (or better than) the NAD C350 pre, P90/3 power combo....I'm still trying to figure out how to get there.

[sublimation]

Hi and Thanx for the reply. It's nice to have some feedback from the practice--as opposed to the theory. I suppose I started thinking of stereo improvements and then read a bunch of threads on the importance of separating amplification from processing...then thinking of ways to reap these benefits without necessitating "significant" spending.
If I'm honest, I'm happy enough with my 3808 as it is, but if I could have gotten a noticeable improvement from a three figure investment...would probably have done so. It's disappointing to hear that your tests showed the 2808 to be a weak/inferior pre-amp...I wonder if anyone else would/could echo this?
It seems odd that Denon would offer those outs and not deliver the kit to justify them.
Maybe it's time to enjoy what I have and just save for the next "big" upgrade.

[indus]

Originally Posted by KelvinS1965

I'm kind of in the process of doing this, but mainly to improve stereo music quality, as I'm fairly happy with the HT sound, using HD soundtracks. I recently did some listening tests using my 2808 as a preamp (in Pure direct mode), my Arcam P1000 power amp and Arcam P90/3 to run the front left and rights (all single wired, no biamping to confuse the issue just yet). Source was an older NAD C540 CD player as it sounds much better than my BluRay player for CDs.

I found that I didn't really hear much difference between the 2808 on it's own or with either Arcam power amp, so I tried another option: I have an older NAD C350 stereo intergrated amp with pre-power amp links on the back. I found that I prefered the NAD on it's own compared to the 2808 on it's own, but then I tried the NAD as a preamp only with the P1000 and the P90/3 and found there was a difference with this combo and the best seemed to be using the NAD as a pre amp, with the P90/3 for power amp duties, using the P1000 was not quite as good as the P90/3.

So my conclusion after all this swopping of amps and cables was that the 2808 isn't a good enough preamp (even in Pure direct mode) to get the best out of the better power amps. It works as a stepping stone to a further upgrade in that it helps share the load using the 2808 only for surround duties and the P90/3 for the front three speakers. However, the sound quality is only changed by a small amount IMHO. Longer term I would like a more 'musical' pre-pro or perhaps a better sounding receiver that could still use the P90/3 via pre outs to give me the stereo sound quality equal to (or better than) the NAD C350 pre, P90/3 power combo....I'm still trying to figure out how to get there.

Kelvin, sorry if I've misunderstood, but did you ever try using the nad stereo amp + denon+ poweramps? ie cd player into stereo amp which is then connected to the denon avr (in pure audio mode) + poweramps?

[KelvinS1965]

No I was trying to see if the Denon preamp was limiting the sound (which it was) so no point in having two pre amp stages then the power amp. Simply put, have the Denon anywhere in the chain compromised the stereo sound, but for now I'm having to use it for pre amp duties with the better of the two power amps until I find a suitable pre processor or better sounding receiver. Note that it does sound slightly better using the Arcam power amp, but not worth the cost (IMHO) unless it's part of a progressive upgrade step, like I'm planing.

[indus]

Originally Posted by KelvinS1965

No I was trying to see if the Denon preamp was limiting the sound (which it was) so no point in having two pre amp stages then the power amp. Simply put, have the Denon anywhere in the chain compromised the stereo sound, but for now I'm having to use it for pre amp duties with the better of the two power amps until I find a suitable pre processor or better sounding receiver. Note that it does sound slightly better using the Arcam power amp, but not worth the cost (IMHO) unless it's part of a progressive upgrade step, like I'm planing.

May I suggest you try it?

2 ch music through only my Onkyo 875 sounds poor.

I now have my quad cdp (that has a built in preamp) going into the analogue input for cd on the Onkyo. I then have a quad 909 poweramp connected to the L and R preouts of the 875.
I get very good results. I've often done back to back swaps, and this set up sounds very close to NOT having the 875 in the equation ie to just Quad CDP + Quad 909 poweramp (the latter could be described as audiophile by many)
I can't explain why this should be, and take your point on two preamp stages but it works.
I'm not technically minded, but maybe, if a dedicated stereo preamp processes the signal first, it improves things, ie it just passes through the avr with minimal alteration corruption?

Anyway, if you have all the kit lying around, why not try it, nothing to lose.

[KelvinS1965]

Maybe the 875 does less processing to the analogue signal, or is simply just a better sounding preamp than the 2808? I might give it try just for fun, but it wouldn't be a permenant solution as it would further increase the number of boxes and I'm running out of space.

I did mean to try using just 2 of the 7.1 'external' inputs on the 2808 incase it is a more direct route (though I can't see what the point of 'Pure direct' on the other inputs would be if this turns out to be true).

[KelvinS1965]

I didn't have time to try the daisy chained input setup suggested above, but today I did swap the CD RCA cables over to the front left and right inputs on my 2808's 'external 7.1 inputs'. These are really for inputing a 7.1 analogue signal from a BluRay/SACD player that has decoding onboard, so there is no EQ, delays, or tone controls for this signal. I figured that as I don't use them for anything, it was worth a demo to see if they offered an improved sound compared to the

I may be suffering from placebo effect, but I'm sure it sounds better through these inputs rather when than when using the 'CD' input and setting the 2808 to 'Pure direct'. 'Pure direct' must still have some analogue to digital & back to analogue conversion as it allows delays and room EQ that the external mode doesn't. I wonder if the external input means that the signal remains in analogue or at least has a less torturous route to the pre amp outputs? Comparing the two inputs (with all levels matched) using only full range for the speakers and no subwoofer seems to give a sound that I'm happier with.

I'd been thinking about making a small 'passive' box that would allow my CD to go directly to the power amp inputs via some resistors to set a comfortable fixed level. Using a relay or switch to allow me to share the 2808's left and right preamp outputs with the same power amp inputs as the CD. I'll carry out a bit more listening (including going back to the 'CD' input plus Pure Direct on the 2808 to cross check), but I think this might be good enough to save me the hassle of making up this 'passive' box.

So if the OP is still reading after this ramble it might be worth trying your ext in for CD use if you want an improved stereo result with your proposed power amp upgrade.