Hi All,

I am new to Car SQ. I'm thinking to buy a Sub.
I did some research and thinking to buy this sub:

Boston G210-44 10"
- Speaker Size 10"
- Rated RMS power handling 300 watts
- Recommended Enclosure 0.5ft ?(14.2 L) volume sealed

I think I will connect this sub as a 2-ohm, so that my amp got the followig outputs:
3 Ch 140Wx2(4-ohm) + 260Wx1(4-ohm), more power to the sub.

Do you think this is a good sub, under my current setup?

I am not thinking to buy a dedicated amp for the sub at this moment.

Do you have any suggestion, which sub will fit my current setting?

My budget is about 300 for new sub, 200 for second hand sub, any suggestions?

Here is my current setting:

HU: Alpine CDA-9885 (USB)
Front: Focal 165V Slim (60W RMS)
Rear: Factory Speaker
Sub: Researhing .....
Amp: Audison Srx5, 3 Ch 150Wx2(4-ohm) + 160Wx1(4-ohm)
Other: Stinger, Dynamat Extreme (all doors)


Thanks.

should be fine. u have a typo, which originally had me worried...


it's 1x260wrms@2ohm

boston make very good subs, with the G2 the baby brother of the G5 which quite a few measq competitors use (including myself and sierra)

you say u dont intend to buy a dedicated mono "at this stage"...might be better to get the audison srx4, and run ch3+4 bridged to power the sub.
i really only recommend 5ch amps if the person is sure they wont be changing amp set-ups for several years...otherwise, if u do buy a 5ch, ur often left with a disused channel when u upgrade to a dedicated sub amp

Yes, it's typo.
It should be 3 Ch 140Wx2(4-ohm) + 260Wx1(2-ohm)

In fact, I had also considered the Digital Designs sub, but DD is designed for vented box only, as least their website only provides the vented box diagram. It's difficult to make a good vented box. I heard that all sub boxes should be designed for the particular sub, the generic box will not yield the best out of any particular sub. That's why I started to search another sub, and found this one.

I was also thinking to buy a new SRx4, just so happen I found a second hand Srx5 in this forum. That's why I brought it. The Srx5 is a bit bigger than Srx4, but if you don't mind the unused sub channel and the size, it's not bad as it got more power


Spyne, thank you for your reply.
I feel more comfortable to buy the G210 now.

Hi,

My amp can have the following output options:

1) 5Ch 55Wx4 (4Ω)+ 185Wx 1 (4Ω)
2) 5Ch 75Wx 4 (2Ω)+ 160Wx 1 (4Ω)
3) 5Ch 50Wx4 (4Ω)+ 300Wx 1 (2Ω)
4) 5Ch 70Wx 4 (2Ω)+ 260Wx 1 (2Ω)
5) 3Ch 150Wx 2 (4Ω)+ 160Wx 1 (4Ω)
6) 3Ch 140Wx 2 (4Ω)+ 260Wx 1 (2Ω)

My front Speakers is Focal 165V Slim (60W RMS) and connected to the amp output.
I don't connect the rear speakers to the amp, just connect to the HU speaker output.

If I am going to connect the Boston G210-44 to my amp.
Boston G210-44
- Speaker Size 10"
- Rated RMS power handling 300 watts

I am not sure whether I should use option (5) or option (6), any suggestions?

Any sound quality different between 2-ohm an 4-ohm?

Just to know more before I do the configuration.

Millions thanks.

You can't connect your G210-44 up to option 5, as your sub is Dual 4ohms, meaning it can wire to 2 or 8ohms.

So you could either use option 3 or option 6. Option 3 leaves 2 channels unused (perhaps for rear speakers if you have them) as the Focals are only 60rms, so option 3 could power them fine, though you don't have extra power on tap if, and the gains may be set a bit higher. Option 6 means no rears off the amp, but you have a bit more power for the fronts, and only slightly less for the sub. I'd probably go Option 6, but that's up to you. Just make sure you set the gains right and you won't overpower your splits.

Hi,

I just brought the G21244. The saleperson told me that G21244 and G21044 run the same rms (300W), and G21244 will be better. I accepted him recommendation and brought the G21244.

However, I found that my amp output is (It may be an old model):
- 50Wx4 (4-ohm) + 180W(4-ohm)
- 75Wx4 (2-ohm) + 180W(4-ohm)
- 150Wx2(4-ohm) + 180W(4-ohm)

That guy told me that G21244 default is 4-ohm, and can connect to my amp (I show him my amp's manual.)
He then connected the sub to my amp (using the default fuse configuration, i think it's 2-ohm). It's work, but I didn't know how's the sound because it's not in the sub box.

I told that guy this sub only support 2-ohm and 8-ohm, but he said it's ok for my amp.

Can anyone tell me what happen?
What is my amp real output under this connection?
What is the sub real ohm?
Is that ok to connect this sub to my amp?

Many thanks.

the g21244 has dual 4ohm voice coils, meaning it can only be wired to 2 ohm, or to 8 ohm, as louie said.

you amp will run it, as long as it is stable to 2ohm.

what amp do you have?

Audison Srx5, supports the following outputs:

- 50Wx4 (4-ohm) + 180W(4-ohm)
- 75Wx4 (2-ohm) + 180W(4-ohm)
- 150Wx2(4-ohm) + 180W(4-ohm)

If I run in 2-ohm, does it mean the output is 360W?

Do you think i should go back to G210-4 10", that's a 4-ohm model?

Thanks.

ok, the srx5 will run a sub at 2ohm.

with a 4ohm load on the speaker channels, it will make 300wrms

with a 2ohm load on the speaker channsels, it will make 260wrms

this is fine for your sub

Thank you, mate.

I think the latest model should support 2-ohm.

But this is a second hand amp, and the owner's manual said:

Load Impedance:
Front and Rear/Sub ...... 4-2 Ohms/4Ohms

Output Power (RMS) @ 13.8 VDC; THD 1%
- 50Wx4 (4-ohm) + 180W(4-ohm)
- 75Wx4 (2-ohm) + 180W(4-ohm)
- 150Wx2(4-ohm) + 180W(4-ohm)

That's why I am a bit confused.

Hi,

I did some research on the internet again.
The following summarize what i found:

===========================================================================
The amp puts out more power at lower resistances. Sound quality, on the other hand, is sacrificed at lower resistances. So at 8 ohms the amp might put out much less power than it will at 2 ohms, but the actual quality of the signal and the 'damping factor' of the amp is sort of compromised by operating with that level of power and low impedence .

If you hook up a lower impedance (e.g. 2-ohm, less rocks) than the amp is designed for, the amp can draw too much current and overheat, going into protect mode (truck overspeeds and blows engine). If you hook up a higher impedance (e.g. 8-ohms, more rocks) than the amp is designed for, the amp has to work harder to push the load (can't go as fast) and can also overheat and go into protect mode.

Generally, it's a LOT safer running at higher than lower recommended impedance.
===========================================================================

It looks like I am learning Physics ....

I will ask the shop to change a 4-ohm sub for me. I hope they will.

Thank you, mates. I learnt a lesson.

Where did you find that junk? Most of it is a load of bollocks!!

Amps going into protect on 8ohm loads because 'they have to work harder'?? Seriously, who thinks up that crap? Overheat? Heat is generated by current. Current is substantially lowered at the higher impedances. So is the heat. Higher impedances require higher voltages, not current. Thats why power output sags.

And ignore damping Factors completely. They are such complete bollocks, and taken so far out of context, it has taken on a 'spec' of its own.

Running at 2ohm, with a dual 4, is not a problem at all. You'll be able to do it all day without a problem. If you do have a problem, its not because of the sub.

Higher impedances is better for Power compression, but you get less power. Lower impedances is better for power, but you're more likely to get power compression. If the amp is stable at the lower impedance, you're laughing. Nothing more

I think something wrong with my conclusion.
Forgive me if i am wrong, just start learning.

BTW, do you think the following statement is correct?

"The amp puts out more power at lower resistances. Sound quality, on the other hand, is sacrificed at lower resistances."



Regarding to "Running at 2ohm, with a dual 4, is not a problem at all. If you do have a problem, its not because of the sub". I am agree. The problem is not the sub, the problem is the amp, it is not designed for 2ohm.


Just want to know, assume I am using this configure 150Wx2(4-ohm) + 180W(4-ohm), which sub do you think I should go for G212-4? or G212-44?

Thank you

Not a problem!

If the amp is not 2ohm stable, then you can only run it at 4ohm or higher. If you're not running it off a Mono-block, you'll need all the power available, so getting the dual 2 is the best bet.

If the amp IS 2ohm stable, then getting the dual 4 is the best bet.

Oh, too bad.

The saleperson told me that Boston supplier told him all the stocked Boston G210 has problem (he mentioned that the magnet had problem). That why they cannot delivery it.

It frustrated me that I got this answer after waiting for two weeks.

Any body heard about that?

How can I verify it?

Thanks

Not so. Many users have had great results with our woofers in sealed boxes.

However, like most subs, ours will play louder and lower in a ported box.

Phil

mmmmh, I had checked with the supplier, they don't have stock issue.


The dealer told me a single 4-ohm DVC sub could run in 4-ohm
The dealer told me 10" subwoofer is not popular and the supplier didn't have stock.
The dealer told me all the G210 has problem that why the supplier didn't ship the item.
.....

This is a good example of how the professional shop deal with their customer.

Well someone didn't want your business..... What were they trying to push you to buy instead? (I'm assuming it would be another brand)

Technically it can run in 4ohms, however you will be shorting out one of the coils, which messes up all the other specifications, and really shouldn't be done, why waste money on a sub if you're not using it right eh.

Did they happen to tell you what the problem was, or just that it had a problem?

Really doesn't seem like they were interested in helping you at all

He told me that the G210's magnet has some problem.


It seems that he wants me to buy something he has stock or another brand.