How To Improve B&W N802 Bass Response?

[jteoh1]

I’m not satisfied with the bass response of my current system in stereo. It seems weak and doesn’t seem to fill the room at low to mid volume. I’m looking for any ideas or suggestions on improving the bass response. My application is mainly 50/50 stereo music / multi-channel HT. Listening room dimension is 24’(W) x 17’(D) x 20’(H) with openings to living room, foyer, kitchen and sun room.

System configuration:
• Digital sources: Sony DVP-NS 755 DVD Player and Scientific Atlanta 8300HD Cable Box
• Digital-Analogue Converter: Apogee Mini DAC (1 week away from being replaced by Apogee Rosetta 200 DAC and Big Ben Clock Regenerator)
• Preamp: McIntosh C200
• Amps: 2 x McIntosh 501 monoblocks
• Speakers: B&W N802
• Cables: Mogami balanced XLR interconnects (soon to be replaced with Apogee Wyde Eye for all interconnects), Cobalt copper speaker cables bi-wired to N802s.
• Receiver: Denon 5803 (for HT only passing thru C200)

I had tried a few configurations along the way, though I’m not satisfied yet, they may be interesting tips for some of you with similar components:
• Canare L-4E6S Star Quad balanced XLR cables tend to “filter” out mid and high frequencies to a point that the sound becomes muddy.
• Belden 1800F XLR balanced cables are better than Canare where they are clearer and seem to give the illusion of sound stage opening.
• Mogami XLR balanced cables better than the above in my system. They are very transparent, clearer and sound stage opens up tremendously.
• Setting the output trim to +12 on C200 makes a lot of difference. It drastically improves details and sound stage even further.
• Connecting N802 low frequency taps to 8ohm and mid/high freq to 4ohm taps of MC502 helps. The bass response seems to be louder and the mid/high seems to be “sweeter” and just right.

I shall soon see what kind of performance improvements from the Apogee XLR cables, Rosetta 200 and Big Ben.

I’m also considering getting a good sub to extend the lower frequency. In my initial research, the SVS PB12 Ultra/2 ($2300) sub seems interesting. It has 1000W BASH digital amp and 2 x 12” TC Sound Ultra drivers. Anybody has any opinion about this sub for music application? I’m wondering how well it blends in with the N802s. I’m not sure how good the 1000W BASH amp is compared to McIntosh MC501 monoblocks. Would I be better off getting passive sub and let the 501’s drive it?

As an alternative to sub, would a 2-channel equalizer help boost the low frequencies of N802s to make frequency spectrum “flatter” at a given db? I hate to waste my investment on N802s, I mean the spec says it can go down to 30Hz. My reservation of EQ is it stretches out my signal path (dtx EQ has AD and AD built-in, in addition to my Apogee DA in the signal path). Not sure if this latency will lead to video syncing problem for HT application. Also, I don’t want to find myself having tinker with EQ’s instead of enjoying the music. If you have good experience with EQ, please share your experience about the brand(s) you tried.

I will appreciate any suggestions you may have on improving the bass response.

Thanks,
John

[akhter]

I was pretty dissappointed with the 'punchiness' bass of my N804 Bi-amped (2x100w) via ARAM AVR300, until a few days ago, while walking around the room, I heard good bass. Up till that point I was determined to get a Velodyne DD-12 (which I still plan on in a few months) as that is supposed to be one of the most 'accurate' subs on the market and the 'room correction' feature. While walking around the room I found out that ar certain areas, I heard much better bass. Then I had to move around my speaker a lot, and eventually got much better bass 'depth'. I don't know the sceintific reason behind it, but play around a bit. However, if you are like me and are used to have a sub, then, you'll need a sub (especially if you listen to Rock or House music or movies).

[js24]

---Connecting N802 low frequency taps to 8ohm and mid/high freq to 4ohm taps of MC502 helps. The bass response seems to be louder and the mid/high seems to be “sweeter” and just right.----

I've alwasy wondered about this idea of "connecting to optimal loads" of the Mcintosh design...
however, shouldn't the bass go to the 4 ohm tap since that's where the impedence drops?
the mid and high stay around and above 8ohm for most of the B&W but the power hungriness comes from the low end...--- at least this was what i thought.
have you tried it the other way around???
I'm just curious and I don't own a Mac so... lemme know~~

[perato]

If you haven't done so already, you should check the frequency response of your total system, including the room. You can buy or make a test tone CD and buy a sound level meter to measure the frequency response. Calculate your room modes to verify the variations in frequency response make sense. Then you can decide about subwoofer, equalization, or room treatments.

[jteoh1]

---Connecting N802 low frequency taps to 8ohm and mid/high freq to 4ohm taps of MC502 helps. The bass response seems to be louder and the mid/high seems to be “sweeter” and just right.----

I've alwasy wondered about this idea of "connecting to optimal loads" of the Mcintosh design...
however, shouldn't the bass go to the 4 ohm tap since that's where the impedence drops?
the mid and high stay around and above 8ohm for most of the B&W but the power hungriness comes from the low end...--- at least this was what i thought.
have you tried it the other way around???
I'm just curious and I don't own a Mac so... lemme know~~

I have tried different combinations of ohm taps with the McIntosh. The 4 ohm and 2 ohm taps decrease the bass response substantially, the exact reverse of what I originally imagined. The 8 Ohm taps tell the McIntosh amp that it is driving a higher impedance (8 ohm) speaker, therefore it is delivering more current to the speaker, hence a better bass response. Now, connecting N802 mid/high to 8 ohm decreases the musicality sharply. It drives the Nautilus midrange so well that it eclipses the sweetness of tweeter. The chimes of bells and triangles are covered up by the over powered midrange. I found the 8ohm taps connected to low frequency and 4ohm taps to mid/high is still the best configuration.

[jteoh1]

If you haven't done so already, you should check the frequency response of your total system, including the room. You can buy or make a test tone CD and buy a sound level meter to measure the frequency response. Calculate your room modes to verify the variations in frequency response make sense. Then you can decide about subwoofer, equalization, or room treatments.

Good idea... I have an SPL meter and am planning to move it around to check the db variations in the room with only the bass taps of N802s plugged in. Unfortunately, it does not report frequency response may have to invest one with the feature, should be a fun toy to play with.

[jteoh1]

Weak Bass Solution Found

I’m thrilled to share with you that I’ve found the solution to my weak bass problem. I picked up the dbx equalizer (model 1231 for $300) this evening and added it my signal path, between pre-amp and amp, with balanced XLR connections. Wow, I was totally amazed what a difference this EQ makes! The bass now can extend way down low to 30Hz the B&W N802 woofers are capable of producing. The bass is extremely crisp, deep, tight, solid and punchy yet extremely musical. I can easily discern and appreciate every single low musical note. The N802s now sound like a pair of stereo subs and actually make the room rumble when watching Toy Story 2. I really don’t need a sub any more.

The EQ has +/-12db boost, it seems to “boost” the sensitivity of N802s, making N802s become alive! The midrange and high frequencies also benefit from this EQ. My system now sounds sweeter than ever.

I was looking at the Auralex acoustic treatments earlier today but was concerned about making my family room unsightly (sure won’t pass WAF). What a relief, this EQ did such a wonderful room correction job that I no longer need the acoustic treatments now.

Interestingly, I also installed the Apogee Big Ben (clock generator), nah, it didn’t improve the sound a single bit. My Apogee Mini DAC’s dual stage design is so jitter immune that making Big Ben absolutely unnecessary. The BB is going back…

Boy, am I satisfied with the big bass now! I’m glad this has been an inexpensive but highly effective solution. Thanks to all, nonetheless.

John

[caleb]

I am amazed that you needed to go to these lengths to get good bass from your 802's.
I have never had a problem with mine and I just have the source, processor and amp in the line.

[RobP]

Hmmmmmm. Finally, someone in home audio/ Home theatre using 31 band EQ's. These have been used for years in recording studios. In movie theatres they use them as well, but each channel has its own 31 bands. I have talked to many "audiophiles" that scoff at the idea of using equalizers, but if they are used to record the sound, why not use them to reproduce the sound? The next step would be to get a RTA and eq your room. Just be careful not to get too crazy with it, a rule of thumb is no more than 3db +/- per 1/3 octave. Good Job!