Cheapy sub for a newbie

Ziade2006

Active Member
Hi, i am quite new to AV world and I recently got a Sony STRDH-800 receiver, 2 Mordaunt 902, 2 Mordaunt 902i, 1 Mordaunt Ms304 and a Gale storm 8 sub. I want to build a DIY Sub if it will provide a significant improvement to my actual sub. I want to know it the followings will be ok (I am choosing cheap components because it is my first DIY sub and don't want to spend a lot, it is more of an experiment):

1) JBL GT-5 12"
2) Amplifier 200w (COMPACT HIFI KARAOKE PA AMPLIFIER 200W MAX 2x MIC INPUT *FREE P&P SPECIAL OFFER (5420047111944) | eBay)

Thanks for all replies and merry chrishmas to you all


 

Member 639844

Former Advertiser
Model the sub first and see what power you need from that. You could make a nice ported sub from that driver and make a fair bit of difference over what you have now.
 

Ziade2006

Active Member
I plan to use one of my 600w PSU to power the receiver via 12v - i want to know whether this receiver i mentioned will be enough for the jbl sub. Also, to forgo the construction of the box, will the jbx that comes already boxed for car bring any difference to my gale? (i know the boxes are not good enough for home use, but still, will it be better than the small gale?
 

8ace

Active Member
I got hold of a Detonation panel amp for one of my builds delivered from Germany for less than £80(Not sure of the company name but I can probably find it may have been these guys http://www.lautsprechershop.de/inde...www.lautsprechershop.de/hifi/amplifier_en.htm ) and its pretty powerful I'm running an 8" jbl of it sounds great http://www.avforums.com/forums/diy-subwoofer-build/1446854-my-completed-pc-sub.html I'm pretty sure the spec sheet was different to what those guys list positive it was 125Wrms @ 4ohm

You're gonna need quite a lot of power to run a 12" GT5 properly I've seen 700wrmw pushed through a single 12" Gt5 and it loved it 200w peak is just gonna tickle it :D They are great budget drivers. That amp is a stereo amp and it doesn't look like you can bridge it not sure if it's filtered to run a sub either. Also it states 8-16 ohm(don't know if thats per ch or not) I think Gt5's are 4 ohm Single Voice coil so you may burn it out quick if it aint 4 ohm stable. If the GT5 is a dual voice coil(which I don't think they are but the 1202D & 1204 are) you will be able to use both channels(could use 2 x GT5) but your still stuck for sub filtering unless you're doing it on your amp/receiver ?
 
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8ace

Active Member
Yes gt5 are single coil. Will the dt 50 be enough power for it in your opinion?


It powers my 8" GTO804 great, would run a 12" fine depends what you want really as moonfly has said a ported box will be louder but they take a bit more skill to design right. Sealed boxes are easy but need more power(w) to achieve the same volume as a ported box. Bk electronics do panel amps BSBP200 but they're not cheap CPC used to do them but looks like they don't now.

ebay seems to have some too nowadays :thumbsup: not sure what they're like though 250W Pure Bass Subwoofer Amplifier + Panel + Transformer (All in one) | eBay

http://www.ebay.co.uk/itm/550W-Pure...98?pt=Speakers_Subwoofers&hash=item19cb75de06

Quoted toshiba components: may be a good buy....I feel another build coming on....No transformer in the second one??? Not sure what that's all about
 
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Ziade2006

Active Member
they look nice but i do not have funds, i am a student and recently spent quite some cash on receiver and speakers. I think i've set my heart on this:Skytec SPL400 Watt DJ PA Home Hifi Amplifier at best price! Does 200w at 4 ohms and hopefully it will provide an improvement on my gale. because it's got 2 outs i wonder if i can connect 2 subs to it
 

8ace

Active Member
Looks a lot more suited to that sub. Think you'll have to connect 2 subs as I wouldn't have thought it was bridgable to a single channel(good thing is the GT5's are lovely and cheap), looks good though. You could instead use a dual voice coil sub(2x4ohm coils) to run both left and right channels to a single sub and run twice the power through a single sub. The JBL 1202D would have been a good option on a budget(I just sold 2 brand new ones for £45 and in a lot of opinions are better than the GT5 plus they take more power) but think the coils are 2x2ohm I don't think there is a 2x4ohm version.

Have you got full control of the the sub frequencies from the reciever otherwise you may have to fit some sort of crossover/filter into the equation.
 
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8ace

Active Member
They quote for those speakers "Dual 4-ohm 1 1/2' Voice Coils" and the amp you mentioned does "Speaker Impedance: 4 ohms minimum"

So you could use just one of those Alphasonik with both channels hooked up to it. In effect 1x DVC (2x4ohm) is the same as 2x 4ohm speakers

Re. 2 of the the JBL 1202D's could be wired like this and used on your amp in question(Skytec SPL400 Watt DJ PA Home Hifi Amplifier) Subwoofer Wiring Diagrams, One 2 ohm Dual Voice Coil (DVC) Speaker (the bottom config to show 4ohm per channel) but witha single 1202D you won't be able to achieve a 2x4ohm load on that amp

or 2x 4ohm SVC GT5's ...one per channel
 
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8ace

Active Member
No probs always nice to see new builds Done 2 home ones, 1 on pc & 1 on my Yammy Rxv3900 an XLS 200 clone with a peerles XLS 10 but bigger amp, same panel amp as one of the leema acoutics subs that goes lovely and clean and loud.

Done a good few car builds too last one was 130db+ using 2x1202d's & 1 in progress at moment using slightly more upmarket kit.

Big sounds is always good and you never grow out of it :D

If I had a dry outbuilding I'd be completly deaf by now
 

8ace

Active Member


They can be wired to show either a 2 ohm or an 8 ohm load per speaker so just bear that in mind when you choose your amp

You can usually get away with an amp seeing a higher resistance speaker but not a lower resistance one than the amp is designed to work with. The amp will be overloading. Happy building :thumbsup:
 

8ace

Active Member
As the alphas have 2x4ohm coils you'd prob do better running just one of those as my above post. You'd get the full 200wrms then.

I found a little more info on the amp here DJ Speakers, Disco Lights, PA Systems, Lighting & Effects, DJ Equipment, DJ Kits - Skytec SPL400 2x 200W MAX Power PA Amplifier

it shows RMS @ 4 Ohms (W) 2 x 100 (would be one alpgha connected to both channel)

or

RMS @ 8 Ohms (W) 2 x 50 (2 alphas configured to give 8ohms)

The amp is not 2 ohm stable so you can't use that option
 

Ziade2006

Active Member
I might not be better but can you connect 1 channel to each sub on 1 coil? Is it doable or it is obligatory to connect both coils for it to work ? (Really sorry i know am asking a lot of silly questions but to be honest i have never even hold a bare sub driver in my hands!)
 

Member 639844

Former Advertiser
As the alphas have 2x4ohm coils you'd prob do better running just one of those as my above post. You'd get the full 200wrms then.

I found a little more info on the amp here DJ Speakers, Disco Lights, PA Systems, Lighting & Effects, DJ Equipment, DJ Kits - Skytec SPL400 2x 200W MAX Power PA Amplifier

it shows RMS @ 4 Ohms (W) 2 x 100 (would be one alpgha connected to both channel)

or

RMS @ 8 Ohms (W) 2 x 50 (2 alphas configured to give 8ohms)

The amp is not 2 ohm stable so you can't use that option

Its also weaker than Mr Muscle and entirely unfit for subwoofer amplification duties, especially home audio subs.
 

8ace

Active Member
Its also weaker than Mr Muscle and entirely unfit for subwoofer amplification duties, especially home audio subs.


If It was wired to a single driver, the 4ohm DVC it would be giving 200wrms(100w per coil). I would have though that would be ok for the alphasonik sub in question on a budget anyways.
 

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