Axiom Home Page Forums General Discussion Stereo More power for fronts-best way?

I have a Denon AVR-989 rated at 115 WPC, but I would like to play louder in two channel stereo. Any suggestions to get more power to my M60's?

1SS, the 989(2809)has a maximum power capacity that's more than what's needed for most situations, with peak SPL numbers a little over 105dB in typical listening positions. Have you measured the actual SPL numbers that you're getting, because the present capability should be extremely loud and more would be dangerous to hearing?

You have pre-outs on that unit if you want more juice.

Well, I haven't tested max db yet, but I know that at higher volumes, the sound seems a little strained, especially higher frequencies. I would like to get that volume without, I guess, straining the amp or nearing its max. I don't think it's the speakers to blame for what sounds like distortion.

To get reference levels of 76 db band limited pink noise using DVE, I have to turn it to +7.

So, I'm a little vague on the pre-outs. How would I connect another amp if I wanted to for 2 channel without affecting the settings for multi-channel?

Maybe I'm crazy, but that seems way off to me. If the speaker levels are calibrated properly you shouldn't be anywhere near +7 in order to hit 76dB. Did you check speaker levels with SPL meter or run Audyssey? What are the speaker levels set to in the Denon?

Yeah, that doesn't sound right at all. I don't calibrate to 70dB any more, but on my 75wpc H/K, I was only at -15 or so (out of I dunno, +10?) for 70 on DVE. OTOH, the pink noise tests on DVE are WAY WAY WAY WAY WAY WAY quieter than the intro and test tracks. Like 20-30 dB quieter.

I need a new calibration DVD.

Really? Maybe that's what he's experiencing then. On regular listening material he shouldn't be near +7 to hit 76dB though.

76dB should use about a tenth of a watt.

No offense, John, but I'd love to hear from an audio engineer on that topic. Either that, or show me the math.

Ken, the anechoic sensitivity rating on the M60s is 89dB per 1 watt at 1 meter. Taking into account both direct sound and room reflections, sound level in typical rooms at home drops off at about 3dB per doubling of distance(e.g.,Toole, p.60). At a typical listening distance of around 10' the sound level for 1 watt would be about 85dB. 10dB lower would use a tenth of a watt(95dB would use 10 watts, 105dB would use 100 watts).

Hi 1sweetspot,

Welcome to the Axiom Forums. Something is very, very wrong with your Denon setup. As JohnK has pointed out, your Denon's power output should drive the M60s to extremely loud playback levels without audible distortion.

It's easier to adjust the pink-noise levels manually using the Dolby Digital test signal built into the Denon. Turn off Audyssey, and use the rotating pink-noise Dolby signal at either 80 dB SPL or 85 dB SPL (75 db is too quiet to make precise adjustments by ear).

Pay special attention to the front left main, center, and front right main level settings in your Denon menu. Set them to 0 dB. I think you have all the level settings way too low.

Be careful about turning up the Denon volume control too high, as you may drive the amp into clipping which could damage the tweeters in your speakers.

Regards,
Alan

Hi 1sweetspot,

First check your speaker trim levels as they could be set too low. Your system might not be calibrated properly and if you used the auto setup on your Denon it is a possible culprit. What are the front LEFT/Right trim levels set to?

You should also check any settings like the "Night Mode" feature (if it has it) and Dynamic Range Compression (DRC) to see if they are activated. If so turn them off.

Ken, I believe you've just been served.

I believe so.

With all the years you've been here Ken you should have known better LOL

Okay, first off, thanks for all your input guys! I have run Audissey and double checked using SPL meter. Here are some Stats:

sub on, set to LFE and mains
crossovers at 80hz front, 80hz center, 90hz surround, LFE at 90hz.

For "Direct/stereo", fronts at large, sub on LFE+Mains, crossover set to 40hz

Channel levels:
FR 0.0
C -2.5
FL 0.0
SR-6.5
SL-6.0
SW-11.5

Again, running band limited pink noise using DVE, reference level is +7 to achieve target of 76db.

Full bandwidth pink noise is 85 db at +7.

Using receiver test tones, 85 db at +7

When I listen to a CD using these settings under stereo mode, "0" on my receiver gives me SPL of 99db.

Maybe everything is OK and this is as good as it gets?

Maybe so, but my suggestion would be to use the Audyssey calibration and if the setting for the M60s is other than "Small" with an 80Hz crossover, manually change the results to that. The M60s should never be set "Large" and the "+Mains" sub setting shouldn't be used, just "LFE". You're working the M60s and 989 harder than you have to, instead of letting that fine sub take the lowest bass load off of them. The -11.5 calibration result for the sub indicates that the level setting on the sub amp itself should be turned a bit lower so that the calibration comes out closer to 0.

I should clarify that-fronts using Audyssey were originally set to large for everything, but I changed it so that they are set to small and crossed over at 80hz for mutichannel, but set to large for stereo as I prefer the fuller sound.

I don't really understand the term "headroom", but I thought by having my sub volume up a little more (it is just under halfway) it would lessen the strain on my receiver during HT, no? Better to have channels set as close to zero as possible?

Should my front and surround channels be increased to aprrox. +3 and -3, keeping them closer to zero, and then the master volume would be a little lower to reach reference level? Or just trust Audyssey...

Hi 1sweetspot,

Don't trust Audyssey. With a problem such as this, I would do a full reset on the Denon (read owners manual) with so many factors possibly in play. This will change everything back to the factory/default settings. This would also disable any whacky dynamic range settings which could also compromise output (if enabled).

Once you do the reset, go back in the Denon settings and re-enter the trim values, speakers set to small, 80hz crossover you already have manually and skip Audyssey for now. Re-run your tests. The best way to verify these settings is with an SPL meter as Alan suggested. One of the best tools an audiophile can make. And yes you can try increasing all the values and see where this takes you if you plan on doing everything by ear.

As for your subwoofer, the pre-out signal it receives might be low with a -11.5 setting. Turn down the gain on the subwoofer control and increase the pre-out setting of -11.5.

I had to turn the gain down nearly a 1/4 turn on my DSP3400 as I was getting readings of -12db or something similar on the sub.It is now within 1-2db. I can't help but wonder if there is some other problem here. I am using a Denon 2809, virtual twin of the 989, and whether I have my fronts set to large OR small, turning my Denon to +7 on the volume is painfull if you're anywhere near the system.

As Doc says, you should dial the gain back on your sub a little...try an 1/8th of a turn to start, try running Audyssey again to see what the new setting is for the sub. It should move closer to "0". Make further adjustments if necessary, it doesn't have to read "0" but should be much closer than "-11.5".

Okay, cool. More tweaking. If there is some dynamic range function interfering, this in theory should correct my 2 channel quality at high volumes.

Out of curiousity, Adrian, what is your spl at "0" when listening to CDs? I'm testing from approx 11' from the fronts and getting 99db. That would give me some idea if the output is correct for the receiver.

Thanks in advance!

On some Denons they have a feature what is called Night Mode. If activated it limits SPL and dynamic range and if you would try to crank the volume with it activated the speakers would definitely sound strained. I have not looked up if your Denon unit has this or not. It should also have a feature called Dynamic Range Compression. Check to make sure they are turned off.

Shouldn't it go back to the default once the receiver has been turned off?

Not sure which feature you are talking about. This is why I asked him to reset the processor. Although I am not sure if he has decided to do this.

Sorry, I don't have a sound metre, but it's loud enough to hear the bass on the catwalk at the side of my house...loud. Btw, I should mention I have M80s, but still, you should be going borderline deaf if you are listening to that reciever/M60's at '7', imo.

That sounds about right to me. If you are wanting it even louder than that you really should be looking into a separate amp. All you do is connect the amp to the preouts on the back of the avr with rca's just like a cd/dvd player's analog connections. Then run Audyssey or adjust speaker level outputs as usual.

Is the signal from the receiver to the extra amp and amplified signal, or is it like the preout to a subwoofer-basically not amplified?

The reason I ask is if the wattage is "stacked"-if my receiver is putting out 115 wpc and the external is 100 wpc, does that mean 215 wpc are going to my speakers, or is the receiver's amp bypassed and only the external amp handling the signal?

Output to a separate amplifier is always un-amplified. I expect you would fry the input to your amp if you fed it an amplified signal.

Makes sense. So, anyone have any recommendations for a more powerful (more than 120 wpc) 2 channel amp?

The best bang for the buck would be, IMO, used 2 channel amps, Outlaw Audio's M2200 monoblock(2 of them) and proamps like Qsc, Behringer, Crown to name a few, but these amps tend to have slightly noisy fans in them.

Emotiva XPA-2 or XPA-3 seem to be pretty good.