[sk456]

Originally Posted by navin

If you get the chance listen to
Wilson Audio
Vandersteen
B&W 800 series
Wilson Benesch
JM Labs/Focal Utopia series
Sonus Faber
KEF's bigger speakers 105, 104, 107, 207 etc..
Martin Logan

If by chance anyone is wondering one would need to sell his/her mid sized sedan ( selling a santro like mine will not cut the deal ) to buy any one of them.
And if by any chance anyone is givign any of them away... im always there with a begging bowl.

[gunbir]

Originally Posted by anupmathur

Class D amps differ not just in the power supply, but also in the operating mode of the amp itself. The whole amp works in switching mode. Pulse width modulation is used and more often than not the output stages will be MOSFETs.

Performance matches good Class AB designs and heat dissipation is very low. Efficiencies of 90% are achievable. And, as someone wanted to know, the damping factors are VERY impressive, making these amps very desirable for bass.

While Damping Factor itself is a much abused concept that people rarely understand, Class D amps having higher Damping Factor is a myth. The truth is Class D amps have lower Damping Factor than most class AB amps due to lack of feedback. By employing feedback circuits, Class D designers are still trying to match Class AB performance.

Another myth, most Class D amps are more efficient. The truth is that most Class D amps are in fact more efficient at 4ohms. But at lower impedances, they are as efficient / inefficient as Class AB amps, at times with higher distortion too.

So while Class D is great for some applications, its going to be a while before I will consider them better than Class AB. However, If there is any newer information that can enlighten me, I am open to changing my mind.

[Venki555]

Do you think I hv to get the damping done for the vibrating to stop. Also, I want to get my left comp working, Is there someone who can fix it.

Looking to get this sorted out. Inputs are appreciated.

[navin]

Originally Posted by sk456

If by chance anyone is wondering one would need to sell his/her mid sized sedan

actually the base versions are not that expensive and are pretty good too.

and in my view speakers are really easy to DIY. Many of the drivers are easily available.

[DerAlte]

Navin, how easy is easy as in 'easily available'? Surely you don't mean in India, do you? Last I attempted they wanted my bank statement as proof of interest before they would divulge any information.

[navin]

Originally Posted by DerAlte

Navin, how easy is easy as in 'easily available'? Surely you don't mean in India, do you? Last I attempted they wanted my bank statement as proof of interest before they would divulge any information.

No not in India. but today you ar free to import. I've had not problems with customs etc.. as long as I pay the relevant duties and taxes. Granted I have not used the common large retailers (Madisound, Solen, Zalytron, etc..) and that the sources I have used are not available to the public at large (my age has some merit after all) but I meant that if you want to import raw drivers and/or crosspver compnents today you are free to do so.

[DerAlte]

Originally Posted by navin

... the sources I have used are not available to the public at large (my age has some merit after all) ...

Indubitably so, o master alchemist!

So far, I have never been able to trust buying anything so far without touching and feeling. The only things I have bought online so far has been a battery and RAM for my geriatric laptop (Y2K vintage Toshiba). And everytime I set my sight on buying something, my trip gets cancelled! Jinxed.

[navin]

Originally Posted by DerAlte

Indubitably so, o master alchemist!

No alchemy involved. I know the products I import well. The risk involved is minimal.

[clipto333]

navinji,

i have a query. this thing is really bothering me.

i wanted to know how do manufacturers calculate what component(caps, inductor etc.) to use to come up with the required crossover frequency?

My Hertz Energy components(2-way) have a xo frequency of 3.5 khz. The value of the inductor is .22mH and the cap is 5.6uf. the tweeter xo has a 12db/oct slope.

The midbass has a 6d/oct slope. the value of the inductor is .1mH.

So, when i use an online calculator i never get the same component values for same xo point. i Tried different alignments too. so why is this happening? is there anything im missing?

One more thing. Most xos i have seen have just a single resistor(as opposed to an L-Pad) for attenuation. whats the reason behind this? won't the impedance of the driver shift by using just one resistor?

Also, i have seen xo's with +db setting. How can this be done? And how is this possible? A crossover doesn't have an amplifying circuit/device so how can the level be increased from 0db to +--dB? Or is it just that the manufacturers label the 0db setting as +db and the rest accordingly?

cheers

[low_bass_makker]

Originally Posted by clipto333

My Hertz Energy components(2-way) have a xo frequency of 3.5 khz. The value of the inductor is .22mH and the cap is 5.6uf. the tweeter xo has a 12db/oct slope.

The midbass has a 6d/oct slope. the value of the inductor is .1mH.

Also, i have seen xo's with +db setting. How can this be done? And how is this possible? A crossover doesn't have an amplifying circuit/device so how can the level be increased from 0db to +--dB? Or is it just that the manufacturers label the 0db setting as +db and the rest accordingly?

cheers

The Impedance of the driver also depends If the tweeter is have 6 ohms when compared to 4 ohms then the value will change which cause the xo point to drop. Try increasing the impedance in the calculator.

Also the -3db, 0 db, +3db is in the crossover the -3 and 0 is achieved due to the resistance but the +3 db is due to the sensitivity of the drivers. Like the tweeter will have higher sensitivity than the mid bass when played at same level.

[navin]

Originally Posted by clipto333

My Hertz Energy components(2-way) have a xo frequency of 3.5 khz. The value of the inductor is .22mH and the cap is 5.6uf. the tweeter xo has a 12db/oct slope.
The midbass has a 6d/oct slope. the value of the inductor is .1mH.

So, when i use an online calculator i never get the same component values for same xo point. i Tried different alignments too. so why is this happening? is there anything im missing?

manufacturers take into account the drivers impedance at turnover frequency, the drivers natural roll off and impulse response, and the "effective nominal system impedance" they are trying to achieve.

There are many XO design software out there. One free software is called LSPCad Lite. While there is not much you can do with it, playing with it can help you understand what the manufacturer intended to do. If you have FRD data of the drivers so much the better.

[nishantgandhi]

I was looking for a branded sealed subwoofer and had finalized on CS-1204B or the Blaupunkt Gtb 1200c. What other choices exist for a branded sealed sub?

Also, I have been hearing that CS 1204B is phased out. On top of it, the successor, GT5 does not have a sealed box in 1204 series (only a BR and tube). But just a few days ago a member had reported having installed the CS 1204B. Sam/others, could you please clarify the confusion?

I am a newbie to this and not sure whether I would want to get a sub and then the box built separately. Hence I thought of going for a ready made solution. Please help here.

[adityamunshi]

Have you considered buying a branded enclosure ? Some of our members are using a bassworx sealed enclosure, i think it retails for 1.2-1.8 K

Gurus please clarify regarding the quality of such enclosures.

Originally Posted by nishantgandhi

I was looking for a branded sealed subwoofer and had finalized on CS-1204B or the Blaupunkt Gtb 1200c. What other choices exist for a branded sealed sub?

Also, I have been hearing that CS 1204B is phased out. On top of it, the successor, GT5 does not have a sealed box in 1204 series (only a BR and tube). But just a few days ago a member had reported having installed the CS 1204B. Sam/others, could you please clarify the confusion?

I am a newbie to this and not sure whether I would want to get a sub and then the box built separately. Hence I thought of going for a ready made solution. Please help here.

[nishantgandhi]

Originally Posted by adityamunshi

Have you considered buying a branded enclosure ? Some of our members are using a bassworx sealed enclosure, i think it retails for 1.2-1.8 K

Gurus please clarify regarding the quality of such enclosures.

Oh I did not know such an option existed as well. Can you share some more details? Website, availability in Mumbai?

EDIT: IS it this one? are these really 'one-size-fits-all- kind of ready-made solution?

[adityamunshi]

Just search for 'bassworx' in the sound off show off section. I remember Moralfibre used one before he made one himself, and devarshi84 uses one too.

I dont know about sizes. The gurus can clarify.

Originally Posted by nishantgandhi

Oh I did not know such an option existed as well. Can you share some more details? Website, availability in Mumbai?

EDIT: IS it this one? are these really 'one-size-fits-all- kind of ready-made solution?