Axiom Home Page Forums General Discussion Home Theater Add power amp for "fuller" sound?

Hi everyone.

I've been using a Denon 3805 receiver to drive my system (M60s, VP150, QS8s & SVS PB-12/2) for the last couple of years, since I upgraded to the Axioms. While the sound is clear and detailed I keep feeling like I'm missing something, lately leading me to conclude that it sounds a little "thin", especially on 2 channel "direct" playback. I have tweaked the system to hell and back in the last couple of years and I know the sub is well calibrated.

So this weekend I swapped in my old Harmon Kardon AVR-65 receiver just to see what it would sound like. I only wired up the M60s using an optical connection to a my CD player and did some back to back comparisons. While the HK lacked a fair bit of the detail of the Denon it had a fuller sound with quite a bit more punch. Overall it was a slightly smoother sound, with more prominent midrange and midbass. It also appears to be much more powerful amp (approx 10dB at same indicated output of -15dB). I used my level meter to ensure comparisons were equal in volume.

So, of course now I'm wandering down the upgrade path again and wondering whether adding a separate power amp like the Emotiva LPA-1 or the Outlaw 7125 to my Denon will give me the fuller sound I am looking for.

For now I am happy enough with the feature set of the Denon, as I do not yet need the Dolby HD decoding features etc of the new receiver generation. Of course the other option would to replace the receiver anyway, perhaps with something like the Marantz 7002 - but right now that would be stretching my budget and I don't really want to downgrade.

I would appreciate your expertise and opinions as the only local retailers are chains or really expensive boutiques with very limited inventory, so I would have to cross my fingers and use the buy and see method.

Dave

Only one to know for sure if you will notice a difference, buy the amps and have a listen, you can use the Denon as the PRE/PRO and even if you don't notice much of a difference you now have the beginings of a nice seperate system and when the time comes you can just buy a new PRE/PRO with the features you are looking for.

FWIW, others on this site have mentioned better low end and crisper highs with seperate amps.

Hey Jason,

I definitely don't want crisper highs. I am seeking a smoother, more balanced sound. I was just doing some more comparisons there and the HK sounds more cohesive and balanced in sound levels across the instruments, while the Denon really emphasises the higher range of cymbals and guitars and seems to lack a fair bit of punch.

I think it is probably as much to do with the DAC as the amp, so a new receiver will probably have to be the route to go.

I guess crisper wasn't the word balanced, as you said.

Dave, any competently designed amplifier, including those in receivers, has been designed to amplify transparently without adding any audible coloration to the sound. If you want sound that's "fuller", "smoother" or whatever other characteristic, you should be looking elsewhere other than to the amplification. The original source material, the speakers, the listening room and the way you set these up all affect the sound.

Is it a valid test of the amp's power to compare the volume output based on the displayed gain setting of two different receivers? I don't know the answer myself, it just seems that a lot of different variables could play into that effect. (just one for example, the Denon's auto-room calibration that boosts certain frequencies and dampens others to produce the smoothest response in-room)

Jason

No. That display is arbitrary by manufacturer, and also is not constant. If, say, you have the mains calibrated at -5dB, it will certainly not be the same volume on the same level on the display as if you have the mains calibrated at +7dB.

I realize the power readout may be misleading as even though they achieved the same sound level with HK -21dB (cal 0dB) and Denon -15dB (cal +5dB) either could introduce distortion at any level. This is obviously not an indication of max output.

Just let me say that the sound difference between these two is not subtle and they are both run flat, with no EQ of any kind. On the Denon I had to adjust the bass by +3dB and treble by -2dB to come close to sounding the same as the HK.

I had thought it was maybe DAC related since I let the receiver decode all my sources, so I dug out an old Audio Alchemy off board DAC and hooked that up. The same sound characteristics were still present so the tonal difference is from within the receiver, whether it be the preamp, amp, or some kind of hidden EQ in either.

Dave