Getting good sound quality below 200Hz


I run open baffles with currently 15" Eminence Alpha bass drivers with their dedicated Rotel amp and crossed over at 200Hz with 24db slope.

This underpins the upper driver beautifully but by contrast if I play it on its own its not at all impressive, lacking primarily in both definition around the sounds and also impact.

My first question "is this typical of what sound is like below 200Hz"

Secondly looking to improve this should I concentrate on improving the 15"drivers or the amp?

 

Please don’t recommend a powered sub as I have one already which will eventually underpin the 15"drivers when I have that bit right.

Thanks

bumpy48

Send them-in to Danny R! loL

sorry couldn’t resist.

audioaural site has some basic info that may help here.

 

This is one of the reasons why certain songs sound way better than others with respect to bass. The building blocks of having better bass, is to make sure you have the bass frequencies in their proper positions. 

Having clean bass frequencies is enough to get amazing bass through any audio system.

The bass frequencies are from 20Hz to 160Hz. The best frequencies to boost for bass in a song, are around 50Hz and 80Hz. These frequencies make sure that the bass sounds full and powerful. All bases should be subjected to a bell curve at the key of the song.

Bass in an audio track is between the 20 to 400Hz range of frequencies. The frequencies are shorter and longer when compared to the higher frequencies.

I probably missed it here, but, are you running a system with two fifteens per side? One crossed over to the other? I am confused and your question is interesting. By the way I play and have recorded bass.

+1 recherche

Awesome experiment... Demonstrates/Presents this problem from the Opposite direction.

Which comes first?

The Instrument or the Playback Equipment?

@bumpy48,

"Is there a reason why this may be, and are there any lower sensitivity 15" drivers that I could think about. Power is not an issue as I have a 1000Wpc Ice amp available."

There may well be reasons, but if so, they’re above my pay grade. I’m no driver designer or TS parameter expert. But, I think that it’s not so much that there might be exceptions, so much as there might be ’near-exceptions’ to some sort of iron law for it that I’ve never been able to work out. Part of that problem is that traditionally woofers are hardly ever designed for specific applications from the ground up, instead they’re usually ’crosspollinated’ and shoehorned into more or less filling a need. Many, many woofer designs out there are "dual" or "multi" purpose, convenient for the manufacturer maybe, but a compromise for the user no matter which way with them you go.

That’s really what I happen to like about Acoustic Elegance. John up there in Michigan never makes a woofer until he has gone back to the drawing board and has fully and independently designed and manufactured, all in-house, just one, single, definitive model (from any, one maker, that should be all you need) for each and every possible woofer category (infinite-baffle, bass-reflex, bandpass, sealed, etc, etc)...no need screw around with anything dual-purpose ever again. That allows you to start with the app alone and then buy someone’s deliberately best-conceived design for that app. From there, you basically just choose the woofer size, and how many of them, you need. What you get is something designed for your, particular app that was never compromised from the start.

But, don’t let anyone kid you, bass response in the room is really one of the very hardest things to get right in all of audio, even when going ’by the book’. And depending on how ambitious or not you want to be with it all will certainly dictate what you might want to try. But, IME, I find that the ’just right’ level of bass performance is a very difficult thing to try ’sneak up on’ and hit on without any overspending at all. For my money, it’s much more successful to get a better woofer and ask it to do something Less than it was designed to do than to ask of the ’just-right’ woofer to do something More than it was designed to do.

In fact, if it were me, I’d be looking at using only one, good driver type (per side) below your 200 Hz xover point. That way you can eliminate the xover to the sub altogether. That’s very important to the overall character of the bass response in the room. The fewer xover points the better, with 3-way systems sounding nearly Always the best, overall. Crossover effects are actually quite audible and even the very best and most expensive of them will degrade the sound to some extent, and if not so much in frequency, then in terms of coherency and dynamics. I think those sorts of advantages can often end up being the first casualties when we get too caught up in chasing the lines on a graph.

Of course, all this is just my 2 cents and it’s mostly so much audio philosophy, but it’s maybe the kind of thing that if my present-day self could go back in time and give audio advice to my 30-year younger self, it would likely include something like that.

My system is multiamped and crossed over with boxcar digital filters. By happy coincidence it crosses from bass to mid at 190hz, and I can shut off the mid/high power amps and just listen to what’s below 190hz, which I do on occasion to be sure channelization is intact on the computer’s soundcard driver before I subject the mid/hi horns to possible damage. I don’t have bass horns, but I do have a pair of Altec 421a 15"ers that are as clean and fast as any woofer, and it sounds like mud. Absolutely all definition and location (aka harmonics) from any bass instrument, even a pipe organ, comes out of the horns. With everything on the bass sounds fabulously crisp.

The room has a ton to do with bass under 200hz. Is your room small or square? 

When I hear about slow, sloppy, undefined bass, it is usually a room with a long decay time and ringing.