[jinu_joseph]

This is bad news.. I had asked for the GTO series and looks like I have the CS series. Sam how much does the CS1204 B cost ?? I paid Rs 7350.

[Sam Kapasi]

Originally Posted by jinu_joseph

This is bad news.. I had asked for the GTO series and looks like I have the CS series. Sam how much does the CS1204 B cost ?? I paid Rs 7350.

No no, this is not bad news. Technically that is a GT4-12 subwoofer (as you can see from the picture) so it's only named a CS for strategic reasons.
The CS1204B costs 7990/- and if you like tight bass, is probably your best bet as it is the only sealed box in that lot.

[jinu_joseph]

That is a relief, yes my primary interest is that it should be tight bass.. Thanks Sam.

Going back to my areas i want improved in my current setup:
1. I still find the boom effect in some sound tracks. I dont like the boom effect because i feel it lingers on for a little more than it should and kind of spoils the original soundtrack. So how do we tighten the bass further.

2. My HU allows me to decide the crossover frequency for Sub output. Currently its kept at 80Hz, sound wise i feel this gives the best effect. Is this the cause of the Boom effect in some sound tracks.. should I increase it or decrease this freq for tighter bass.

3. Also on the amp as per the manual I have kept the crossover frequency setting to the max freq (320HZ).

4. Regarding playback.. Audio CD sounds absolutely brilliant. I feel like shifting my residence to my car. I could attain Nirvana there. After listening to audio CD, MP3 cds suck.. its like as though some one removed all the bass from the track. All my mp3s are encoded at 256kps from original audio cds. FM radio is the worst .. there seems to be absolutely no or very minimal bass.. there is also some level of hissing on some channels like 98.3 FM. Any ideas to improve performance.

[navin]

Originally Posted by jinu_joseph

That is a relief, yes my primary interest is that it should be tight bass.. Thanks Sam.

Going back to my areas i want improved in my current setup:
1. I still find the boom effect in some sound tracks.
4. Regarding playback.. Audio CD sounds absolutely brilliant.

Is it the sub that is boom or the trunk? I know this is not practical while you are driving but for testing play your system with your trunk open and see if you like that sound. once we know what to fix the fix itself will be easier to define.

[jinu_joseph]

Navin, Its the sub that goes boom for certain notes. Will try your suggesstion and get back.

[jinu_joseph]

Navin I tried it with the boot door open, it totally eliminates the Boom effect, but it also softens the bass a lot. So what do you suggest.

[low_bass_makker]

Originally Posted by jinu_joseph

Navin I tried it with the boot door open, it totally eliminates the Boom effect, but it also softens the bass a lot. So what do you suggest.

try differnt positions of the sub like sub facing the back in the front side ways this will help a lot.....

[navin]

try this...Sam might not recommend this but it wont hurt as long as you are careful...

get some blu tak. measure out about 3 pieces of 5gms (I used a gold merchants scale) now CAREFULLY stick one piece at a time to the dust cap of the woofer and listen. See if it helps. I assume 15gms will do the trick but the idea is to go slow.

BTW do not face the sub up or down doing this. the spider is not designed to handle 15-20gms more weight over time and will sag.

By increasing the Mass of the cone you are changing the mechnical characteristics of the cone (as also resonance frequency) and I guess that might drop the resonances below your threshold of hearing.

this process is reversable. The other option is changing the box loading from sealed to aperiodic but that process is not reverable easily.

[jinu_joseph]

forgive my ignorance but what is "blu tak"

[jkdas]

Originally Posted by jinu_joseph

forgive my ignorance but what is "blu tak"

" Re-useable multipurpose pliable adhesive and non-toxic"

its blue tack

details...
http://www.madsci.org/posts/archives...1591.Ph.r.html


http://www.amazon.co.uk/gp/product/B...nce&n=11052651

phew!

[santosh.s]

Originally Posted by navin

By increasing the Mass of the cone you are changing the mechnical characteristics of the cone (as also resonance frequency) and I guess that might drop the resonances below your threshold of hearing.

A doubt...by doing that transient response will also be degraded, it will become slower, right? Also, will it adversely affect damping? I was wondering whether these effects will lead to noticeably sluggish response and consequently loss of punch/tightness in bass, which most of us would not like (jinu being one of them)

[Bass&Trouble]

Originally Posted by santosh.s

A doubt...by doing that transient response will also be degraded, it will become slower, right? Also, will it adversely affect damping? I was wondering whether these effects will lead to noticeably sluggish response and consequently loss of punch/tightness in bass, which most of us would not like (jinu being one of them)

You're right Santosh, there is a limit to mass addition in cones and in general, to the overall oscillating assembly of a dynamic loudspeaker. Some brands overdo it (especially in car audio) to the extent that it is just acceptable and does not fall prey to severe consequences.

Impulse-response charachteristics are adversely affected, so you have to have overcome this with huge magnets or designs with tons of BL. Efficiency goes for a toss. If the spider is not strong enough, the cone sags (in whichever direction depending on how you hold it due to gravity). And you can actually hear the voice coil rub when you mount such a driver in a plane perpendicular to the ground. This would happen in a really poor design, but I have heard one such prototype. It's a good feeling, the mass is so high that when you hold the driver in free air fed with a 20Hz tone at about 10volts, it's hard to retain your grip, there's so much momentum.

[navin]

Originally Posted by santosh.s

A doubt...by doing that transient response will also be degraded, it will become slower, right? Also, will it adversely affect damping? I was wondering whether these effects will lead to noticeably sluggish response and consequently loss of punch/tightness in bass, which most of us would not like (jinu being one of them)

Santosh you are very right. However in audio there are no absolutes. The Mms of your woofer is probably about 100gms so an addition 15gms wont hurt it atelast on trials as lon as you dont face the woofer up or down.

as far as the woofer tuning is concerned again adding Mms will reduce the Acceleration Factor (I cant find the greek symbol of "Rho" n my keyboard). but again we are adding only 15gms and we are only using the woofer under 100 or 80Hz. beyond this the only other mods I can think of making the box aperiodic or use a electronic EQ like a Linkwitz Transform and/or damp the panels of the trunk to kill their resonance.

Maybe B&T can come up with somehting different. Wish Gunbir/JB, Sam, Cream and Tool wre around to help.

[santosh.s]

Originally Posted by Bass&Trouble

If the spider is not strong enough, the cone sags (in whichever direction depending on how you hold it due to gravity). And you can actually hear the voice coil rub when you mount such a driver in a plane perpendicular to the ground.

I feel this should be strictly no-no then. Since it will not only spoil sound quality but also the driver itself in long run. In fact that was my 2nd doubt, but to begin with, navin had already mentioned that 15gm for this particular sub shouldn't do any harm... so I didn't ask further.

[navin]

B&T what say you. you know nore about current drivers than I do. Will 15gms damage the woofer in this case.