Changing the 'character' of the bass (1 Viewer)

[dean_g]

I was just curious if anyone here using SVS subs has changed out the Samson for a Crown, or some other pro amp in an attempt to change the character of the bass.

I'm running one 20-39+ with Samson S1000. I have plenty of bass, but would like to tighten things up a bit.

I noticed the Samsons have a fairly low damping factor of 200 -- which makes me think the driver is probably not under the best control.

The Crown K-1 OTOH, has a damping factor of 3000!

Seems to me this would really add to the 'slam' factor.

 

[Michael R Price]

Dean, I don't think the amp would have that much of an effect on bass tightness. Have you experimented with placement, or equalization? You might have some room problems muddying up the bass.

 

[jeff lam]

The Crown is a heck of a lot better than the samson, I'll tell you that much. No fan too on the K series!

 

[John F. Palacio]

I'll bet that SVS should have an answer on this. I concur with Jeff about Crown being a better amp and no fans. Great looking too, I might add.

But I wouldn't put money down on being able to hear the difference.

FYI I added a Paradigm crossover between the sub out of my processor and the Carver feeding my SVS's and "tightened" the curve feeding the subs by setting it at 100Hz. My processor crosses over at 80 Hz but remember these are 6dB/octave filters, so the additional crossover makes for a steeper curve to the subs by attenuating higher frequencies.

This made the sound of the subs "tighter".

Tom? Ron?

 

[dean_g]

Hmm. It has always been my understanding that damping factor is directly related to the control the amp has over the driver.

My placement and room are great. The bass is not 'muddy' by any stretch of the imagination. What I'm looking for is better transient response - 'slam'

 

[John F. Palacio]

"Hmm. It has always been my understanding that damping factor is directly related to the control the amp has over the driver."

You are correct, however past a certain point, I believe it is becomes moot. Somebody correct me here but a damping factor of 200 means that the source is 1/200 of the load?

Or .02 ohms?

Wire becomes a bigger factor here. The Crown would then be .00134 ohms?

Help!!!!!

 

[dean_g]

Interesting. I was thinking along the lines of why a 120wpc Bryston 3B-ST has twice the 'slam' in the bass as opposed to a run-of-the-mill 120wpc receiver or integrated amp.

 

[Michael R Price]

Dean, the Bryston has better bass than a receiver probably because its power supply is "stiff", meaning that even under loads like heavy bass transients, it delivers full voltage to the rest of the amplifier, allowing it to more accurately track the signal. Just a guess.

I agree that damping factor has an effect, but the difference between 200 and 3000 is probably minimal.

It's possible that you would prefer a sealed subwoofer (DIY or otherwise), which will offer a few milliseconds less "group delay" than the vented 20-39 and an otherwise tighter sound, at the expense of output and depth.

However, I still think your room may be a part of this. If your subwoofer hits a note at a room node frequency, the room will prolong the note (reflections) and make it seem slow. I've heard this effect and it might be what you're experiencing. On the other hand, I could be completely misunderstanding this lack of slam you're talking about. By "slam" do you mean that quick impact of a kick drum, the very sudden transient that sort of hits you in the chest?

 

[Chu Gai]

I don't think you'll be getting more slam from your sub by moving to the Crown as opposed to the Samson. I'm a little unclear by what you meant that the bryston has twice the slam of a run of the mill receiver or amp. Can you elaborate?

 

[jeff lam]

Maybe an EQ would help you achieve what you're looking for. A BFD is much cheaper than a new amp.

 

[Chu Gai]

The damping factor of an amplifier is the ratio between the load impedance (8 ohms) and the source impedance of the amplifier. Modern amplifiers are basically voltage sources and have low output impedances. In essence, what that means is their output voltage is independent (over a wide range) of load impedance.
Now if some company has a high damping factor, they're going to roll that spec out. This is largely a marketing thing the purpose of which is to suggest that amps with lower damping factors just aren't as good.
Dean, if you're of the feeling that your system just doesn't have the slam, you need to analyze the frequency characteristics of your room. More likely than not, there's a resonance and if so, it is this that is largely responsible for your impressions. Once you've controlled it, your satisfaction should improve immensely.
If you choose to buy the Crown, you'll have bought quite a nice amp but you won't have done a damned thing to improve matters.

 

[LaMarcus]

Gee whiz, you guys are just too smart for me. Did ya'll go to sound class or something, shit.

Dean I didn't know you had a SVS.

 

[Chris Tsutsui]

Do you guys think he's going to get more slam if he gets a parametric equalizer and lowers the volume of his peaks?

I think that if he wants slam, he should see about getting or making a new enclosure for the sub with a higher Q and slam factor.

Also remember that too much tightness in the bass from transistor amps can actually be the bass sounding "dry", robbing it of weight, body, and presence.

Without that weight, the bass lacks believability... BTW, this does not mean get a boomy sub.

If anyone wanted to hear the dryest bass in the world, I'll demo for them my 2 tempests through a filter using rusted lamp wire in a highly damped room. When I take off the filter, and use nice wire the bass just comes to life.

 

[Brett DiMichele]

Chris,
How in gods name did you get copper to rust?
I trust you mean badly oxidized lamp wire?
Heh!

 

[steve nn]

Dean I think this is one of the reasons I like my 25-31 CS+ so much. With a tune of 25 versus the 20 that comes with the 20-39, I get the slam and tightness of bass that I like so much. Now I'm not saying that the 20-39 cant deliver what your looking for by NO STRETCH. I'm just saying that I have tried both 20--25 tunes out and I (myself) prefer the 25 Hz tune and maybe it addresses your desire in bass? With the authority of extension capabilities with the SVS products and coupled with what LFE material that is available on most sound tracks, I feel from trying out both tunes that the 25 Hz tune serves me and possibly you very well?? It's to bad you cant go up 5 Hz in tune instead of just down (but still a very nice option) to try it out and see what you think. My previous 15" duel setup afforded me 1/2 of the spl capabilities in the lower Freqs than what I realize from one (soon to be two) 25-31 CS+'s.

 

[PaulDF]

Jeff... Or others...

Can you please clarify on how to use a BFD to most effectively increase the SLAM factor?

 

[Michael R Price]

Paul,

The BFD lets you play with the tone of the bass. By adding (or removing) peaks and dips from the frequence response you can change the sound... for example reducing the level under 30Hz might make the bass sound tighter and increasing the level between 40-60Hz might make it sound fuller or boomier (those are complete guesses, though). I'm sure it would be fun to mess around with, and you'd get pretty good control of how the bass sounds.

 

[PaulDF]

I have been messing with my BFD for a while now, but can't quite seem to figure out where the "meat" of a hard bass hit is....

I guess to clarify my question, where on average should I cut or boost my signal to give my bass a harder louder hit. I just realized now that this might be largely dependent upon the sub/box alignment/size.

lately I am boosting between 30 to 80 hz, peaking at about 5 db around 63. It pounds pretty hard but still doesn't sound right to me. What sounds good on one song might not sound good on another. I thought there might be other BFD users out there who have found a nice tight bass curve setting.

I don't much like to boost my signal, so I don't want to boost any part of my sub signal unless it actually sounds better to me. I hope somebody can understand what I'm talking about...

 

[Manuel Delaflor]

What *exactly* you mean by "slam" dean? (by the way hi there, I have see you on Klipsch forum)
Some people heard that "slam" at around 40Hz, a sub wich can go deeper will sound less impressive, unless you can reach more dB's at the very low frequencies.
For example, some Cerwin Vega lovers will not change their 35Hz boxes for anything, because the CW really kicks (talking in dB's at 40Hz or so).
Just an idea, don't know if it is at all what you were talking about...

 

[Michael R Price]

Paul, you could try to remove the lower frequencies either with a big cut centered on 20Hz, or with some sort of high pass filter. Then increase the overall subwoofer volume a bit. This could make the sub a sound little more like PA-type speakers ("slam"). Also, you might lacking bass slam if your main speakers start to compress at high output in the 80-150Hz range.