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Some people prefer the sound of the mid bass frequency hump as I refer to "thumping". To me its a highly coloured inaccurate peak which I find distracting. I have an old "thumpy" hundred dollar Yamaha sub which I keep in one of my teenager's bedrooms that has peaky coloured sound. It overemphazises that 50-70hz zone which is critical for good reprodution of low frequency sound. Its not a bad sub for rap music or electronica, but for subtle resolution of a string double bass or piano or male voices that peaky humped response gets distracting and annoying to listen too. My kid's friends thought that thumpy sub was pretty cool until they hear the higher resolution that a well integrated EP600 brought to the experience.

If mid-bass hump is your thing, the old SVS subs had that characteristic but also provided greater extension and output. The new improved Ultra subs are quite linear and sound much more detailed as a result. However,they don't thump either. In fact no top flight subwoofer that I know of has that characteristic.

I'm not sure why this keeps coming up but snappy snare drum is not found in the subwoofer. Just disconnect the mains to hear how little the sub contributes. Virtually all that audio contribution comes from the mains with the sub providing subtle LF output. One of the best tests for just how well the sub and mains are aligned for deep kick drum and snappy snare is the old recording by Dave Brubeck, "Take Five" on Time Out. It also has a nice tight string bass rhythm. The EP600 does a wonderful rendition of that recording. The best I have heard from a bass reflex sub and comparable to some great sealed subs.

The fact that a cheap unlinear sub with thump seems to provide better reproduction is further indication of improper setup, especially phase, placement and FR/time alignment irregularities caused by room acoustics. A room with no treatments is a devil's workshop when it comes to accurate sound reproduction and realistic comparison of subwoofers.

John,

The annoying thumping that you describe is very much like what we heard from the SVS PB/12. It got boring very quick. That is not what my Sony sounds like. And the 350v3 thump isn't boring either.

As I've said elsewhere in this post, my Sony isn't an accurate transducer. Nonetheless, it sounds better for music to me regardless of the room.

It will be interesting to hear the SVS Ultra given your comments about how good subs should sound.

What do you think is causing the lack of snap then? Why do I have snap in my Boses and not in the Axioms when they are placed in the same room?

Thanks for the reference on Brubeck. I'll look for that .

So Mojo, from reading you posts it sounds like more the "mid-bass" freq is where you are interested. It seems you can describe others sounds better than your own?

I ask this as I think all here want to experience what it is you desire.

This post seemed to stand out - and seems to point to efieciency in mid-bass, rather than bass.

Could be why thoses with a 600, etc are not hearing this.
Could be why with a "lesser" sub others are.

Hmm. maybe that's why everyone likes M80s WITh a sub (crossed around 40-50)

Tex,

Take Five, besides being one of the jazz masterpieces, is exceptionally well recorded with great range and detail. There is no mistaking the deep bass of the kick drum and snappy snare in the two minute drum/string bass bridge.

I'm going to rule out a problem with the EP600 since you appear to have replaced most parts. Though it is still possible the enclosure itself can be causing undue resonance. In this regard, try lying it on its side and putting heavy articles on it on the middle of one side.

My inferences as to why you are preferring the Sony:

a. Reverberation time as a function of frequency in your room. Your room is untreated with high resonance. Depending on how it is interacting with the subs phase at different frequencies, you are going to get cancellations and reinforcemnts. Your particular untreated room is meshing better with the time/FR characteristics of the Sony sub/M80s at your listening position.

b. You are less sensitive to the higher distortion from the Sony. Distortion in subwoofers is something more easily tolerated than distortion in the midrange or HF.

c. Improper placement of the EP600. Every room is different but in most rooms the sub/sat system is phase aligned when the subs are next to the speakers. The more out of phase the sub is with the mains, the less tight and mushy bass sounds with more frequency irregularities. As an aside, that's the main reason I advise people not to use Audessey or like auto equalization. FR is improved at the expense of time misalignment.

d. Improper integration of the EP600 around the crossover point as a result of the above mentioned phase and room acoustical interaction.

Good points, John.

I found that the sound didn't change when I placed the 600 at my side-wall vs. the front wall. It looked more balanced on the side wall so I just left it there.

As for the distortion, I am almost of the opinion that my Sony is less distorted at lower SPLs than the 600. But again that is only an opinion based on hearing rather than any real data. I say that because the Sony sounds "dryer" than the 600. The 600 adds textures in between the actual notes (which I actually don't mind).

As for the room, I am almost at the point now where I'm going to bring the 600 into my 1,000 cubic foot office which is well-damped. If it sounds different in here, then I'll start attacking the room.

It's interesting that you mention lying the 600 down. That's one of the first things I did after receiving it and listening to it for a week or so. Lying it down did significantly improve the sound. However, I couldn't leave it that way in my room. So I stood it up and laid my beaver on it . The beaver does make a difference and I can actually hear a difference too when I use my hands to hold the sides tightly.

I can't see how the distortion is less in the Sony with a 120W amp, but it is possible. We may be zeroing in on a possible problem which is coloration introduced by the enclosure. Back when these EP600 subs first came out there was lots of discussion at other forums that the size of enclosure merited more bracing. It wasn't an issue with the 500s. I believe there is only one large brace in the EP subs.

While I have never heard problems with my 600 enclosures, with my ear running up and down the sides, it is possible that something might be off in your sub. You mentioned how the sound changed when on its side and you "beavered" it..hmmm...never mind.

Just a shot because I still believe the main culprit is room acoustics and speaker integration, but I'm curious if lying it on its side and putting weight on the middle does much of anything.


Let me know how track 3 "Take Five" from this CD sounds.

Well,

I've never heard that album myself, but I could swear it's in the "New Frontier" video by Donald Fagen.

Lots of interesting comments in this thread. Mojo. Your observations on live performances support my rather distant memories (sad thing that I have not listened to much live music in the last 15 years). I hope that the EP350 dosn't give that thump as I don't like it.

Bad product idea: big red button on the back of the sub, "In case of thump withdrawall, press here"


Hmm... Having done some looking at the specs lately I can tell you two things: 1. there is a bit of a hole in the 100-150Hz range on the M80v2(no more than -3db), 2. there is measurable distortion over that same range. Perhaps the two combine for the effect you notice?

I think this sheds further light on my inquiries in another thread.

Link here

It is interesting to note that the folks as soundstage considered the distortion on the M80s to be significantly low enough to do a second set of measurements as 95 db.

Hmm.. Oportunity for another step up in the line??

Nice beaver pic. I'm...err... relieved.