Any one built a pair of subs? And amp questions

[bank]

Dear All,

In the new year I'm looking at building 2 subs to go with my tops (210w), I have a few questions that I was hoping you'd be able to help out with. Firstly I have an amp which delivers 700w across 2 channels at 4 ohms so 350w a channel or 250w at 8 ohms per channel, I was wondering what wattage sub I should get, 200w, 300w, etc? If it was a 200w that would mean I get 410w total each side?

Also, if any ones built a sub what type of drivers would you recommend? I've looked at the following:

P-Audio SN-15B 15 inch 300W Neodymium Loudspeaker
Eminence Deltalite II 2515 300W 15 inch Driver
P-Audio SN-12MB 12 inch 200W Neodymium Loudspeaker
B&C 12HPL64 12 inch 200W Low Frequency Driver with Neodymium Magnet 8Ohm

Lastly any ideas on a crossover?

Thanks

[colint]

I think it would be a bit pointless using a 12" driver for a sub, there are only one or two 12" drivers that are capable of producing sub bass, you would be better of going for a 15" or 18" driver in a ported reflex cab have a look at the B & C 15's but go for a 400watt driver as a starter because you'll almost certanly need to upgrade your amp!

if you want one amp to power the whole system fit passive crossovers inside the bass cabs
(adam hall do link dynamics crossovers about £40 each)

if you want to run active ( a much better way!) behringer do a crossover for about £60.00 thats not the best in the world but will do the job without to much fuss.

Have a looky here these are about £120.00 each depending on where you buy them.

http://www.bcspeakers.com/index.php?sez=1&categoria=1&id_descrizione=2&prodotto=10&id_descrizione_prod=1

[bluishbob]

I have been looking at this for a while.

As colin says, you want a ported reflex design.

B&C are the best thing to go for as i have found out.

I have been told to stear clear of the eminence delta for bass as they are not very good. At least you should be looking at the eminence kappa.

(see my PM)

[Daryll]

hi Bank.
Look no further than http://billfitzmaurice.com/T30.html.
Cheers

Daryll

[TONYTIGER]

Dear All,

In the new year I'm looking at building 2 subs to go with my tops (210w), I have a few questions that I was hoping you'd be able to help out with. Firstly I have an amp which delivers 700w across 2 channels at 4 ohms so 350w a channel or 250w at 8 ohms per channel, I was wondering what wattage sub I should get, 200w, 300w, etc? If it was a 200w that would mean I get 410w total each side?

Also, if any ones built a sub what type of drivers would you recommend? I've looked at the following:

P-Audio SN-15B 15 inch 300W Neodymium Loudspeaker
Eminence Deltalite II 2515 300W 15 inch Driver
P-Audio SN-12MB 12 inch 200W Neodymium Loudspeaker
B&C 12HPL64 12 inch 200W Low Frequency Driver with Neodymium Magnet 8Ohm

Lastly any ideas on a crossover?

Thanks
Hi Bank so you want to build your own subs ,why? to build a decent pair of subs will cost you a lot more than buying of the shelf its only worth doing if you are going for something top end .My small company has a dedicated woodworking workshop dedicated to building speakers and flight cases and i have been a master cabinet maker for a very long time to build the subs properly is very time consuming. Any way a few tips ,no point running subs in stereo as the human ear cant detect so use your sub amp in bridged mono,decide on design of enclosure that is ported reflex, band pass,or folded horn,get your self some design books as it will save you a lot of time,Fane,Eminence,and Beyma all produce design books.Yes you can use 12" Martin Audio make a cracking 12" sub very compact and loud, choice of drivers will very much depend on type of enclousure as mention B&C ARE OK but there are many to chose from dont overlook Fane, Beyma,RCF, PD,JBL,all good in the right cabinet You will need a very comprehensive range of tools to do the job properly and you will find the price of good materials very costly, but if you have the time it can be a very satisfying job if you need any help just ask.

[Daryll]

Thats excellent advice from TonyTiger.
There is a lot more to building a sub than people think.
I would go along with a proven design, use the correct tools.
With a folded horn the cab needs to be air tight (even a small pin hole will wreck the sound).
With most designs that are on the net, they recoment a driver, use that driver.
I dont know in tony will agree but it`s better to build several smaller subs and "V" couple them should give you a 3db increase, you can also "boundary load " the subs against a wall, do a google on boundary loading.Use the best meterials you can get.Please dont use MDF, yes its cheap but you`ll never lift the cab
The subs can be finished in "Duratex" or the UK version,I think you cab buy some from http://www.aldcroftadhesives.com/productdetails.php?ProductID=92.
good stuff.
Take your time.
At the end of the day it will work out more expensive to build your own, but...and it`s a big but, if all goes well you will have a sub that sounds 10 times more expensive than it is, plus you made it...
Cheers
Daryll

[colint]

Hi Bank so you want to build your own subs ,why? to build a decent pair of subs will cost you a lot more than buying of the shelf its only worth doing if you are going for something top end .My small company has a dedicated woodworking workshop dedicated to building speakers and flight cases and i have been a master cabinet maker for a very long time to build the subs properly is very time consuming. Any way a few tips ,no point running subs in stereo as the human ear cant detect so use your sub amp in bridged mono,decide on design of enclosure that is ported reflex, band pass,or folded horn,get your self some design books as it will save you a lot of time,Fane,Eminence,and Beyma all produce design books.Yes you can use 12" Martin Audio make a cracking 12" sub very compact and loud, choice of drivers will very much depend on type of enclousure as mention B&C ARE OK but there are many to chose from dont overlook Fane, Beyma,RCF, PD,JBL,all good in the right cabinet You will need a very comprehensive range of tools to do the job properly and you will find the price of good materials very costly, but if you have the time it can be a very satisfying job if you need any help just ask.

Sorry to bust your bubble tony but advising someone to bridge a amp without knowing what the load of either the amp or speakers is not very helpfull!

supposing Bank was to build a pair of 8 or 4ohm speakers and the amp will only run safely bridged into 8ohms?

as you say martin audio (& turbosound) do make a 12" bass cab (loaded with a B & C driver) but although both are very good units a 1 x 15" cab would be an instant upgrade and more versatile!

while I do understand the name drop of JBL, PD, Beyma
& Fane (who by the way went to the wall 6 months ago) the reason I would normaly recomend a B & C driver is they have almost become industry standard by being used by Martin audio, Turbosound, and many others.

subject to what you say many people have built their own cabs regardless of not being cabinet makers with fully equiped workshops! which is why I recomended a ported reflex design because they are easy to build!!!!

[colint]

Thats excellent advice from TonyTiger.
There is a lot more to building a sub than people think.
I would go along with a proven design, use the correct tools.
With a folded horn the cab needs to be air tight (even a small pin hole will wreck the sound).
With most designs that are on the net, they recoment a driver, use that driver.
I dont know in tony will agree but it`s better to build several smaller subs and "V" couple them should give you a 3db increase, you can also "boundary load " the subs against a wall, do a google on boundary loading.Use the best meterials you can get.Please dont use MDF, yes its cheap but you`ll never lift the cab
The subs can be finished in "Duratex" or the UK version,I think you cab buy some from http://www.aldcroftadhesives.com/productdetails.php?ProductID=92.
good stuff.
Take your time.
At the end of the day it will work out more expensive to build your own, but...and it`s a big but, if all goes well you will have a sub that sounds 10 times more expensive than it is, plus you made it...
Cheers
Daryll

Boundry loading! good luck with that one!:beer1:

Although I prefer Ply for speakers cabs, there's nothing wrong with using MDF especially if your a first time builder, yes it is heavier and yes it is much cheaper, it's also much denser so is better for bass cabs but won't last so long as ply if it gets knocks & bumps

most people wouldn't dream of constructing a folded horn as a first time build because of the complexity of the design

How can it possably be more expencive to build your own cabs?
excluding the time a 400 watt 1 x 15" bass cab

£15.00 for a sheet of 18mm mdf (or £46.00 for birch ply)
about £5.00 for a box of screws
£5.00 for glue
about £120.00 for a reasonable driver (400watt)
£8.00 for a grill £4.00 for conectors :)

right! :rolleyes:

[Daryll]

Hi Colint.

Granted that it is cheaoer than some cabs.
your estimate is £157.
There are cheaper factory speakers. but how good are they.
But gereraly you are correct :D :D .

Cheers
Daryll

[colint]

Hi Colint.

Granted that it is cheaoer than some cabs.
your estimate is £157.
There are cheaper factory speakers. but how good are they.
But gereraly you are correct :D :D .

Cheers
Daryll

the spec above is for a cab like this but with a lower powered driver
(turbo use the next model up)
http://www.thomann.de/gb/turbosound_txd_115.htm

so think it may be just a bit cheaper! and yes they sound very good even with the smaller driver!

[bluishbob]

out of interest chaps, someone suggested bridging the amp. Surely even 2 8ohms cabs in parallel (making 4ohms) is risking it as unless you buy high quality amps, most won't be able to cope with 4ohms bridges (which = 2ohms)

[colint]

out of interest chaps, someone suggested bridging the amp. Surely even 2 8ohms cabs in parallel (making 4ohms) is risking it as unless you buy high quality amps, most won't be able to cope with 4ohms bridges (which = 2ohms)

Correct (unless you series the speakers = 8ohms) don't bridge a amp unless you know exactly what your doing!
remember that the load changes with heat, load, and movement of the speaker voice coils, so your 4ohm bridged load could swing to 2ohms or lower.

I'm not saying it can't be done and I have done it myself many times but my system is always limited and the only time I've ever seen a clip light on my system is when I set the limiter up!

[TONYTIGER]

Boundry loading! good luck with that one!:beer1:

Although I prefer Ply for speakers cabs, there's nothing wrong with using MDF especially if your a first time builder, yes it is heavier and yes it is much cheaper, it's also much denser so is better for bass cabs but won't last so long as ply if it gets knocks & bumps

most people wouldn't dream of constructing a folded horn as a first time build because of the complexity of the design

How can it possably be more expencive to build your own cabs?
excluding the time a 400 watt 1 x 15" bass cab

£15.00 for a sheet of 18mm mdf (or £46.00 for birch ply)
about £5.00 for a box of screws
£5.00 for glue
about £120.00 for a reasonable driver (400watt)
£8.00 for a grill £4.00 for conectors :)

right! :rolleyes:

Interesting list of materials ,but lets be realistic theres so much missing of this list and heres the difference between doing the job like the pros. never just screw and glue joints they need internal bracing and our top range cabs are also biscuit jointed,no acoustic lining ,no corners or handles,no paint or finishing materials(we spray ours) you will also need extra foam and timber for the front grill(unless you are going to use those naff all in one grills) not seen on pro cabs as i said in my original post its cheaper to buy off the shelf because theres lots of work and cost to produce pro cabs.


Sorry to bust your bubble tony but advising someone to bridge a amp without knowing what the load of either the amp or speakers is not very helpfull!

supposing Bank was to build a pair of 8 or 4ohm speakers and the amp will only run safely bridged into 8ohms?

as you say martin audio (& turbosound) do make a 12" bass cab (loaded with a B & C driver) but although both are very good units a 1 x 15" cab would be an instant upgrade and more versatile!

while I do understand the name drop of JBL, PD, Beyma
& Fane (who by the way went to the wall 6 months ago) the reason I would normaly recomend a B & C driver is they have almost become industry standard by being used by Martin audio, Turbosound, and many others.

subject to what you say many people have built their own cabs regardless of not being cabinet makers with fully equiped workshops! which is why I recomended a ported reflex design because they are easy to build!!!!

Interesting no you have not burst my bubble ,i have a 20k martin audio rig only 9 months old not a B&C driver in sight as far as im aware they have there own drivers made under licence and no they are not industry standard just good drivers ,if i had to make a choice i would go for Beyma they have just been given a design award by PLASA . As for bridging amps this is normal practice for pro PA companys on the bottom end but you need some basic knowledge but my point was not to run sub frequency in stereo as theres no point just bridge and run in mono most manufacturers will give you the specs to tell you if there amps will cope.

[Daryll]

New I would find these somewhere.

http://billfitzmaurice.com/phpBB2/viewtopic.php?t=2170.
I have the plans for these but.........its a daunting task.
I also have the tuba 30 plans and the OMNI 12/10 tops. easier to make but as Tonytiger says there is an lot more than meets the eye.
Just a quick list.

1 x 8 x 4 sheet baltic birch ply
screws
glue
Driver
Piezo or compression driver/s
wire
crossover components
8 x corners
2 x handels
recess speakon plate and sockets.
Wadding for the baffle chamber
either paint or carpet finish.

plus a whole weekend per cab .

Cheers

Daryll

[Excalibur]

Just to inject a thought here, I think the only reason to build your own is to (try to ) make a custom built top end cab. If cost saving is your only aim, I'm sure I can think of a company ( or two even) who could supply good quality gear cheaper than you can self build. Just an observation. :)

[colint]

I think you missing the point tony! not all Dj's can aford a 20k martin rig can they? (although they might want it!) I was talking about a reasonable priced cab for a mobile Dj

I drive an HGV for my sins during the day and deliver to both Martin audio and turbosound! the only drivers I've ever seen go into their premises are RCF compression drivers, some RCF cone drivers, pallet loads of B & C drivers, CLARE cone drivers, and a few pallet's of eighteen sound driver (which are used for the cinema sound stuff) all bearing the martin audio logo!

the grills I use are made by markie the grill www.speakergrills.co.uk
and are full grills with folded edges, not the cheap round things (if thats what your talking about)
Edit :the reason I didn't put handles I the pricing is I don't use them, (I cut handles into the timber) why cut out timber and replace it with a plastic or metal handle, and the same with connector plates.
and my cabs are always braced, and finished with tuffcab paint!

why I envy your talent's as a cabinet maker (and no I'm not being sarcastic) I see no point in biscuit jointing, in 30 years I've never seen a pa cab with anything other than rebated joints.
the other thing that occured to me why on this earth are you using a martin system if your own cabs are so good?

[Solitaire Events Ltd]

the other thing that occured to me why on this earth are you using a martin system if your own cabs are so good?

That crossed my mind too. ;)

[Excalibur]

Dear All,

In the new year I'm looking at building 2 subs to go with my tops (210w), I have a few questions that I was hoping you'd be able to help out with. Firstly I have an amp which delivers 700w across 2 channels at 4 ohms so 350w a channel or 250w at 8 ohms per channel, I was wondering what wattage sub I should get, 200w, 300w, etc? If it was a 200w that would mean I get 410w total each side?

Also, if any ones built a sub what type of drivers would you recommend? I've looked at the following:

P-Audio SN-15B 15 inch 300W Neodymium Loudspeaker
Eminence Deltalite II 2515 300W 15 inch Driver
P-Audio SN-12MB 12 inch 200W Neodymium Loudspeaker
B&C 12HPL64 12 inch 200W Low Frequency Driver with Neodymium Magnet 8Ohm

Lastly any ideas on a crossover?

Thanks

Having just re-read this post I can at last answer the power question. If your amp can do 350w per channel at 4ohms, that is the maximum you will achieve. Therefore for arguments sake, any sub of over 200w should suffice. However, you would, as Colin has stated, do better to buy another amp for your subs, use an active crossover to split the signal to the amps, allowing you to buy an amp for the subs of say 300-400w per side into your chosen impedance. Since you need more power for your subs, this would be a good match.

[TONYTIGER]

That crossed my mind too. ;)

Because clients ask for certain types of equipment for there performance and there is a spec in there contract, if you know about the hire industry this is pretty obvious.


I think you missing the point tony! not all Dj's can aford a 20k martin rig can they? (although they might want it!) I was talking about a reasonable priced cab for a mobile Dj

I drive an HGV for my sins during the day and deliver to both Martin audio and turbosound! the only drivers I've ever seen go into their premises are RCF compression drivers, some RCF cone drivers, pallet loads of B & C drivers, CLARE cone drivers, and a few pallet's of eighteen sound driver (which are used for the cinema sound stuff) all bearing the martin audio logo!

the grills I use are made by markie the grill www.speakergrills.co.uk
and are full grills with folded edges, not the cheap round things (if thats what your talking about)
Edit :the reason I didn't put handles I the pricing is I don't use them, (I cut handles into the timber) why cut out timber and replace it with a plastic or metal handle, and the same with connector plates.
and my cabs are always braced, and finished with tuffcab paint!

why I envy your talent's as a cabinet maker (and no I'm not being sarcastic) I see no point in biscuit jointing, in 30 years I've never seen a pa cab with anything other than rebated joints.
the other thing that occured to me why on this earth are you using a martin system if your own cabs are so good?

Im sure your cabs are great but i was just pointing out you had not priced correct there is no timber for bracing or any paint finish ,and you tell every one to keep it simple now your saying preform handles in cabs not easy for novices and how is anybody going to rebate there cabs with a few simple tools like you harped on about it seems every time i post advice on wood working subjects you are on my case, i only tend to give advice on this forum on subjects that i feel qualified to comment on ,when i post a question about driving HGVs i will wait with bated breath for your advice.:)

[Corabar Steve]

Because clients ask for certain types of equipment for there performance and there is a spec in there contract, if you know about the hire industry this is pretty obvious.

Nowhere in any of your posts did you state they were your hire stock.

Quite frankly I think your condescending attitude is somewhat uncalled for.

This is not the first time I've thought this of comments you've made to members with less technical knowledge than yourself, & there is absolutely no need for it.

[TONYTIGER]

Nowhere in any of your posts did you state they were your hire stock.

Quite frankly I think your condescending attitude is somewhat uncalled for.

This is not the first time I've thought this of comments you've made to members with less technical knowledge than yourself, & there is absolutely no need for it.

Thats rubbish if you read my first post it was constructive and helpful advice from a very experienced cabinet maker and you are just being childish you know quite well that we are a hire company from previous posts on this site and to you personally if your going to contribute to the technical section of this site (which is the only section anybody can take seriously) you should not knock the professionals who take the time and trouble to offer good advice, but don,t worry i shall not be contributing again EVER because its just not worth the agro.:bang: As for attitude you have it in trumps but very little in knowledge or manners. Goodbye.

[Solitaire Events Ltd]

if your going to contribute to the technical section of this site (which is the only section anybody can take seriously) you should not knock the professionals who take the time and trouble to offer good advice, but don,t worry i shall not be contributing again EVER

With comments like that, good. We still have alot of other professionals who are neither patronising nor condescending, such as Colin.

And as for the bit about this section is the only forum that people take seriously, well I suggest you ask our other members.

But in fact you won't be posting again, so it doesn't matter.

[Corabar Steve]

Thats rubbish if you read my first post it was constructive and helpful advice from a very experienced cabinet maker and you are just being childish you know quite well that we are a hire company from previous posts on this site and to you personally if your going to contribute to the technical section of this site (which is the only section anybody can take seriously) you should not knock the professionals who take the time and trouble to offer good advice, but don,t worry i shall not be contributing again EVER because its just not worth the agro.:bang: As for attitude you have it in trumps but very little in knowledge or manners. Goodbye.

I thought about addressing this when I have both the time & inclination, although it does seem a bit pointless & would take the thread off topic.

[bank]

Thanks alot for all the posts, sounds like a pair of b&c's would be what I'm looking for, I had an interesting pm so I'll follow that up as I had a recommendation where to get the drivers.

I've got access to a large amount of tools, so it should be too hard to find the equipment up. So presumably 12mm mdf isn't thick enough? 15mm or 18mm the better choice?

Oh yeah, just to clear it up there are two reasons why I would like to build rather than buy, see if i can do it :) and save a little while I'm at it.

[Jiggles]

It will be A learning curve...