all sifu out there,

can you please clarify something about sub woofer? i got few noob question here

1. SVC Vs DVC? pros n cons
2. what is single magnet and double magnet? izit related to SVC or DVC?
3. how to determine the good specification of a woofer?
4. how to match amp with proper specification of a woofer? eg: impedence, rms
5. how to fully optimize woofer performance?

if possible, can you please answer according to the number.
thank you for ur time and attention. hope u can share some of ur knowledge here.

1. SVC Vs DVC? pros n cons

Generally speaking a DVC has a bit more wire for the coils, and it can handle a bit more power.
Biggest advantage of DVC's is wiring options..
For example a DVC 4 ohm can be wired to 2 or 8 ohms, where as a SVC 4 ohm is only able to stay at 4 ohms.
finally...DVC normally for bigger power handling woofer..means the rms

svc = single voice coil = got only 1 pair of +ve -ve terminal
dvc = double voice coil = got 2 pairs of +ve -ve terminals
dvc pros allows you to feed it more power from your amp by lowering impedance (ohm value) by wiring it in parallel. cons is, u need a suitable amp that is stable at the lowered ohm value.


this is just the number of magnets that u can see at the bottom of the sub, usually higher number of magnet needs higher power to run, not related to the voicecoils.


do your research, read reviews, go to TT, ask other users opinions, etc...read specs only no use, manufacturer can always goreng....


just match rms of the woofer to the amp, vice versa. if its svc 4ohm sub then read the 4ohm mono rating of the amp. if its dvc 4ohm sub then look for the 2ohm mono rating of the sub. usually safe to get amp rating up to 50% higher than sub's rating.
eg) if sub is dvc 4ohm 400W, look for an amp that can go mono 2ohm with 400-600W
if sub is 400W svc, then look for amp that is 4ohm mono with 400-600W


besides feeding it enuff power, u need a strong and rigid box, according to the size recommended by the manufacturer.  dont buy ready made cheap boxes..


This post has been edited by zennn: Aug 6 2009, 01:40 PM

thank you for ur reply sifu zenn, quite clear about this.

but i got further question, mayb u can clarify this as well:
1. ur statement "u need a suitable amp that is stable at the lowered ohm value." usually amp ohm value is at 4ohm, u mean some amp's ohm not stable? going up n down?

2. SVC or DVC can hv double magnet as well?

3. if a sub woofer with double magnet required more power and if my amp not good enough (in rms), then also no use rite? for this case, i better buy single magnet woofer?

This post has been edited by thunder_kiat: Aug 7 2009, 06:09 PM

correct... depending on the specs... dual 2 ohm means u still can either wired it up 1 ohm or 4 ohm which the latter configuration is much better as 2 channel or mono amp is able to wire it up. dual 4 ohms is either 2 ohms or 8 ohms.. etc.. normally for dual 4 ohms, only monoblock is suitable. Not many (and even have its not recommended) to have 2 channel bridged at 2 ohms mono

amp manufacturer will state in their specs how low their amp is stable down to. if youre using single voice coil 4ohm sub, then no problem, most amps are stable at 4ohm mono. if u have a double voice coil 4ohm sub, u will need an amp stable down to 2ohm mono. thats why have to check your amp suitable or not



yes svc can have double magnet also



all u need to do is check the rms of the sub and rms of the amp, doesnt matter how many magnet. get an amp with rms a bit more than rms of the sub. even up to 50% more also ok. less is not ok....but still got sound la. just not as cun

1. SVC Vs DVC? pros n cons
None, just wiring options on a DVC. Performance is/can be the same or better either way.

2. what is single magnet and double magnet? izit related to SVC or DVC?

Single or double stacked magnet, doesn't matter as long as the sub sounds good. Strength and quality of the magnet matters more.

3. how to determine the good specification of a woofer?

By looking at the graph of what it can do. Other specs doesn't really tell you anything but help you find the right ancillaries to match it with.

4. how to match amp with proper specification of a woofer? eg: impedence, rms

Find an amplifier that can handle the specified impedance. The sub will have a safe operating power range. i.e 30w - 500w. Pick a good amp that has a true power rating of anything in between. If you're into SPL, you may want to find something that is on the upper range of the power scale or a little more wouldn't hurt.

5. how to fully optimize woofer performance?

Build a proper enclosure for it (right size, non leaking and suitable for the purpose). A sub does not perform miracles by itself. Building the right box, setting the right frequencies and feeding it clean/wholesome signal will give you more enjoyment that just buying an expensive sub and not knowing what to do with it.

tq sifu zenn and mnkh27.

do you know how much to do custom made woofer box for 12"? where can find cheaper price and where? i mean around kl area

good shops will quote u around 250 for a good sealed box. kl/pj all same la. go to good shops please.

u suggesting the sealed box is better than the ported box? i nvr had any sealed box with woofer to try on. really would like to hear the FACT.

Go join TT listen and compare the sound of seal and port...hard to explain by words actually.

From my experience, If you were used to ported box, u'll find seal box is not loud as ported. However, the bass is more deep and low (thumping bass) unlike using ported box which is boomy. The seal box is much nicer and clean sound. The best thing about seal is you can feel the bass vibrating your heart.

I love seal box but if like to play loud then go for ported box. But it depends to invidual preference and type of music you listen to

i agree with u. what is TT listen?

Izit possible to wire 2 2ohm 300w rms subs with 4ohm 300w rms amp?

its possible... but you will be only feeding each sub with 150w rms

If connected the subs in parallel also it will feed 150w rms only?The amp is 4ohm 300w rms and the subs are 2ohm 300w rms DVC le..

didnt say its a DVC so i assumed its SVC...

that case... yes... amp go down to 2 ohm... and each sub getting 300w rms...

check the JL website for reference...

This post has been edited by craziechild: Aug 12 2009, 06:59 PM

Thanks for the info.

sealed box gives a comparitively flat response or more uniform response (throughout the frequency range) as compared to ported box. thats why used in SQ more, easier to tune (with xover or eq)

ported box will give a high response at certain frequency range only (hence the term tuned ported box), thats why used more in SPL or street bass systems. size of box and size of port will give different frequency responses...

---

Added on August 13, 2009, 4:14 pm

2 units dvc 2 ohm subs? wired in series-parallel gives u 2ohm, wired in parallel-series gives u 2ohm also. if your amp is stable at 2 ohm mono then can la. if it makes 600W at 2ohm, then each sub gets 300W, so its ok. just check the amp specs...

This post has been edited by zennn: Aug 13 2009, 04:14 PM

thank you for all reply, hopefully this can be a good sharing and becomes a FAQ session.

In the future, if there is any RELATED question, please post it over here. so that this might help the ICE beginer in this topic.

regarding this subwoofer,

how to choose the amp ??

CLASS D MONOBLOCK ?

DVC=DOUBLE VOICE COIL ?

mean DVC speaker got 2 +/- wiring terminal ?

regarding this mingwei 12' 1000w sub,

donno got 1 or 2 wiring +/- terminal.

so, the

v-tune monoblock terminal, suitable for this sub or not?

cos im less of budget..

jst can find cheap stuff.

please give me the suitable wiring diagram.

n suitable box.

post some pic ...



Attached thumbnail(s)