Getting good sound quality below 200Hz

A few things.... In general, listening to 150 to 250 hz alone sounds like mud. You are listening to the highest bass regions or more arguably the lowest midrange frequencies. Thanks to @pedroeb for posting a link to the driver. This driver has a QTS of 1.26, that alone tells you that this woofer is ideal in a huge sealed box or free air situation, but also, this very high QTS also tells a story of how this driver can react. Also, you are correct about the graph.  That spike is huge, but crossed at 200hz at 24db per octave that driver is down near 100db by the time it reaches that spike. 

So a few suggestions. Make sure that you use an amplifier with great control over your woofer, it doesn’t have to be tons of power, but most likely should be. You are after an amplifier with good current capabilities.

Placement is critical, this woofer will respond to boundries in the 200hz range like few others. Distance to the floor and rear and side walls all matter.

I suggest that you download Room EQ Wizard software. It is free and works fairly well. I’ve seen it said a few times in this forum to measure speakers very close to the driver. in this case, measure from the seating position first, then move the mic closer to the speakers up and down and side to side and look where your boundries have peaks or dips in the frequencies that you are concerned about. Also look for a hole right above 200.  You do not need a crazy expensive mic, the idea hear isn’t to get accuracy to a tenth of a db, plus or minus 1db will give you a look at what you are dealing with. I suspect that you are dealing with your room. .

When I was a college student in the early 80's we created a tape of many different instruments playing the exact same note.  We used woodwinds, brass, strings, tubular bells, you name it, we had access to the entire orchestra's instrument room.

We then deliberately removed the attack and decay of each note played, leaving only the sustained note.

We then played the tape of notes to a group of listeners and asked them to identify the instrument playing the notes.  And no-one could do it.

We then wrote the instruments on the chalk board and told them these were the instruments they could match up to the notes and played the tape again and only a few were identified.

What this experiment tells us is that the way we perceive an instrument's sound has as much to do with the attack and decay as the note being played.  Thus when you only focus on the lower end of the frequency spectrum of an instrument you are in a similar way eliminating much of what you need to perceive what you are hearing; after all the attach and decay is mostly in the extreme frequencies.

Taken into consideration you might find it interesting to listen to the whole instruments frequencies, and then replace the lower end with different technologies renderings to get a better perception of the whole sound as it changes.

You may find that by nature some technologies render some instruments with lower frequency spectrums more to your liking than others, mostly depending on the instruments overtones and how the attack-decay-sustain sounds overall with the chosen technology.

Cheers

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.