[panny300]

want to upgrade my yammaha yst305 sub but short of funds at present how easy is it to build my own to a really good standard and spec,i don't really know where to start e.g crossovers,cones,ports,baffles etc are there any sites that show step by step and where to buy necessary parts in the uk, can they be as good as the retail versions when they spend thousands on r&D,i am an electrician by trade and am fairly competent at diy(built my own extension for my cinema, why im skint) so is it worth building my own.and if it cost lets say£200-£250 to build, roughly what sort of equivalent retail sub would it equate to.

[GaryG]

Here's a few links that should answer your questions:

http://www.adireaudio.com/diy_audio/...dire/shiva.htm
http://www.adireaudio.com/Files/Seal...plications.PDF
http://www.adireaudio.com/Files/Vent...plications.PDF

http://www.design3dw3.co.uk/audio/audio-subw.htm
http://www.design3dw3.co.uk/audio/audio-hypex.htm

http://members.tripod.com/~terrycthe...um/page12.html
http://www.hometheatertalk.com/DIY_P...ub/ib_sub.html
https://home.comcast.net/~ttriff/
https://home.comcast.net/~ttriff//page2IB-Gallery.html
http://f20.parsimony.net/forum36475/index.htm
http://www.hometheaterforum.com/htfo...?s=&forumid=22
http://hometheatertalk.com/httalk/vi...3e057defacd0a9
http://www.diyaudio.com

[panny300]

thanks for the reply gary looked at the sites a bit over my head at this stage need something a bit more basic eg how large of enclosure, does it need to be ported and if so how large, what size of cone and what freq range is best, how would i know a good speaker cone and amp plate and no one has answered as to how good diy subs are

[GaryG]

To answer your question more directly the Shiva driver and the HS200 amplifer in a suitable enclosure will outperform a Servo 15 in sound quality although not in absolute output. If you need more output then you need to look at a 15" driver, something like the Tempest, preferably a pair of them. The downside to a 15" driver is that it generally needs a bigger cabinet than a 12" to give the same frequency response although you do get higher output.

For a first time effort I would suggest you stick to something straight forward, either a sealed cabinet, or a 'reference' design if going for a ported or passive radiator.

This link should get you up to speed in the differences between the alignments.

http://www.diysubwoofers.org/

When you've digested that come back with your requirements and we'll get you going.

[Mat-Moo]

Also check out Retro and Taz's stuff on here :-
DIY Sub Mk.5 RTP-XR
DIY Sub Mk.3 RTP-12 *Completed*
DIY Sub Mk.4 RTP-X
www.retrotaz.co.uk
DIY Sub Mk.2 RTP-15
DIY Sub Mk.1 RTP-10

I'm getting the parts to build a copy of the rpt-12 in the not too distant future I hope (Also check out Relinquish RELinquished finished which is the same thing, in fact *cough* just printed out the plans for that one from the linked site in that thread!)

[shodan]

Mat, I am the lucky owner of said RTP-12. I've had it for 6 months and I can honestly say that it still surprises me everyday! In fact sometimes it scares me! When I'm watching a movie (and I mean giving it some welly with the volume control) then the dog won't even come upstairs and the ornaments in the cabinet downstair actually shake! How cool is that! Hee hee hee!
If you get yours even half as good (RTP have all the proper industrial toys for making boxes...) then I'll think you'll be very pleased.

Don't know too much about other subs but I really can't imagine anything matching this sub unless you are laying out BIG bucks! If I knew how to do all the proper tests (and understood the results!) then I would do them and put them on here for people to see just how good a DIY sub can be!

[Mat-Moo]

I'm getting all excited! Just need to find 22mm mdf as most places around here only seem to stock 18mm

[GaryG]

This has got me excited!

http://www.adireaudio.com/Files/Dan/Parthenon/

[eviljohn2]

0.8T?!

I'm not sure I'd even want that in the same house as my TV, let alone within a few metres if it's not properly shielded!!!

[buns]

Originally posted by GaryG
This has got me excited!

http://www.adireaudio.com/Files/Dan/Parthenon/

damn, beat me too it....

I wouldnt be so sure on that field either..... quite sufficient to cause dangerous metal object excursions.... or death of pacemaker users!

ad

ps. at those fields you need non magnetic tools..... interetsingly (after you find the cost) will be the attention you get from international terrorism agencies..... such tools are heavily used for bomb purposes

[shodan]

They'll be thinking "submarine" not subwoofer....

[panny300]

thread seems to be going off in another direction,anyway spent the last few nights looking at all the threads that have been kindly recommended plus others,all these snippets of info flying round my mind like a jigsaw.what makes a one subwoofer cone or active amp better than another,is the volume of the box critical,how low of freq should the amp and speaker be rated,wilmslow audio sell a tornado 10,IPL have a sw3 for about £300 how good are they,my yamaha 305 it has 8" speakers rated at 150w with a range from 20hz tried it with two towers only kicked in when sub volume was at 90% adjusting the subs high cut freq cut off dosnt seem to make an dfference so what makes this sub inferior to others,sorry for all the questions just trying to understand it all dont want to spend loads of dosh to find no diference in sound, the rtp12 mentioned above sonds a good project

[GaryG]

Let's start from scratch.

What do you want a sub for? Music, movies or both, in which case which is the priority?

What is the partnering equipment?

What size room will you be using it in?

What is your budget?

[panny300]

sorry to be a pain gary,mainly movies, denon 3802 amp tannoy eyris 2 fronts+centre,harmon kardon dvd,panny 300 proj 7ft screen,18ftx10ft room, £300 tops but if i can get good sound for less that would be better (tightwad)

[GaryG]

That's a fair sized room. My room is 13ft x 8ft and I found that a pair of 15" drivers was needed to really 'feel' the impact of the bass. I would suggest you go for at least a single 15" driver but it would be better if you could stretch to two of them. We'll come back to that later.

Now for the type of sub.

Let's start with the best option first. Can you accomodate an Infinite Baffle sub either in your ceiling or behind one of your walls?

https://home.comcast.net/~ttriff//page2IB-Gallery.html

[panny300]

there is roof space above the room depending on where it would have to be located,so it is possible, would look at all options

[GaryG]

You would need to put the manifold box at the front, in a corner would give the most bass response, behind you is a definite no-no, I tried that and it sounded terrible, had to fix the hole in the ceiling.

I would suggest you try an IB first as you only have make a simple box without any bracing and it gives the best sound quality.

Now on to the drivers and amplifier.

I would suggest you go for two of these:
http://www.partsexpress.com/pe/showd..._ID=7765&DID=7

and amp:
http://www.partsexpress.com/pe/showd...D=118153&DID=7

Total price is around $393 plus around $87 to ship the order to the UK. This works out at around £269 expect to pay around £10 handling fee plus 4% import duty + 17.5% VAT bringing the total to around £341.

For that you will have a subwoofer that will wipe the floor with any commercial sub for less than £2000.

Email juliej@partsexpress.com for a firm quote on the shipping price and expected delivery and give her my regards.

EDIT: Corrected the typo, hit the 5 instead of the 2 in the price of a commercial sub.

[panny300]

thanks for info, if i could'nt fit an IB in my ceiling could you please give me details of the other option of a normal type sub,why can't items similar in spec to the ones quoted above be sourced in the uk.

[GaryG]

The pound is very strong against the dollar at the moment so you get more for your money, which is why I suggested the DVC15. When it comes to DIY subs there are not many options for components in the UK.

Design3DW carry the Tempest (the Parts Express DVC is a clone of the Tempest) at £179 + £14.95 delivery.
http://www.design3dw3.co.uk/audio/audio-subw.htm

BK Electronics do a 200w amp @£150
http://www.bkelec.com/Diy/bsb200.htm


Assuming you decide to buy in the UK and go for a single Tempest then a vented enclosure would probably be your best bet in preference to a sealed enclosure due to it's higher output. Adire have a number of 'Reference' designs for the Tempest so take a look at what they recommend, by using one of their designs you would be able to email them for technical support on building the sub.

http://www.adireaudio.com/Files/Vent...plications.PDF

[panny300]

thanks again for your help

Originally posted by Mat-d-Rat
I'm getting all excited! Just need to find 22mm mdf as most places around here only seem to stock 18mm

I may just be able to help you their

[IronGiant]

Taz and Retro are definitely the people to talk to if you want to build an RTP-12. Relinquished was simply my interpretation of their sub, after looking closely at the outer dimensions of a REL 100Qe and talking to the people at BK, and also discussing it with Taz and Retro before I went ahead. The cutting plan plan mad-d-rat referred to is just the one I came up with for my sub, if anyone can make use of it I'd be extremely happy for them to do so. The original concept is the rtp-12 from retrotaz

Dave

[panny300]

i'm back,looked on parts express at the dvc 15" and 250w bass boost amp, took the specs and input them into win isd beta (as if i know what i am doing) anyway using one speaker in a closed box it came back with a volume of 4ltrs, dimensions of (H) 0.301m
( D )0.141m (W) 204.9mm QTC 0.71 (not fathomed qtc yet) the graph showed 37hz at 3db(is that what you aim for ) next i used a vented box,vol of 8.1ltrs with a tuning freq of 21.69hz QI 7.00 (H)0.370m (D)0.166m (W)247.6mm the vent is 0.102m diam lengh is greyed out, 3db at 22hz on the graph
these dimensions don't look right what am i doing wrong

[ReTrO]

Must be something wrong because your box sizes wouldn't take anything much bigger than a 8" driver (if I'm correct).

I run a Tempest based system at home, it's pretty good.

[panny300]

i think i just discovered where i went wrong,i did'nt change the measurements to match the ones i put in,now i have for a closed box (w)21.09" (h)32.72" (d)13.35" the plot shows 38hz -3db a vb of 114 ltr or 4cuft ,the qtc greyed out at 0.71,
in the specs for the speaker, under dia i put 15" is that right,
for a vented box (w)26.21" (h)40.89" (d)16.42" vb 230.6ltr or 8.1cuft vent dia 4.02" len 5.79" QI 7.00,tuning frequency 21.67hz , 22hz -3db i could'nt get the qes/pe because the pe figure is not in the specs,
do these figures look ok, what frequency at -3db should i be looking for,does any internal bracing or the speaker have to be catered for in the volume. and is there anything else i need to take into consideration before building

[GaryG]

Pe for the DVC 15 is 600w.

Full spec here:
http://www.partsexpress.com/pdf/295-190s.pdf


A ported cabinet with an f3 of 19hz is around 275l (about 9.75 ft^3), remember I said the bigger the speaker the bigger the cabinet.

You could use 2 driver's in an isobaric (face-to-face) configuration like SVS does for the B4, that will halve the size of cabinet you need at the expense of losing efficiency because you're now using 2 motor's to drive the same effective cone area, so you'll need a more powerful amp. Btw, if you're going for ported you want the amp without equalisation (or ask PE how to disable the boost on the boosted amp) because your simulation software assumes a flat frequency response for the supplied power.

Alternatively you could go for the MKIII Titanic driver:
http://www.partsexpress.com/pe/pshow...295-420&ctab=1

This brings your cabinet down to around 200l (about 7 ft^3) for the same response and it can handle 800w instead of 600w. Cheaper than 2 DVC drivers, doesn't shift as much air as 2 DVC but more than 2DVC in an isobaric config.

At that price you're in AV15 territory:
http://www.stryke.com/AVseries.html
which is only another $10. Stryke do not normally carry them as stock, they build a batch and when they're sold you could have a long wait for the next batch to be built. Parts Express are a bigger operation and will ship when you order and you'll get them in 2-3 weeks.

Personally, I'd say stop mucking about and get one of these:
http://www.adireaudio.com/diy_audio/...ire/tumult.htm

If I ever get the pair I ordered in November, I'll let you know how they sound!

EDIT:
Btw, WinISD Pro (alpha) is the better of the two versions, if you have Excel then use Unibox it's much easier to understand.
http://www.danbbs.dk/~ko/ubmodel.htm

[panny300]

thanks gary bet you wished you had never answered keep thinking i have got a toe hold on this and go crashing down again
i downloaded all the spec of the dvc from parts express but did not know what the pe meant, probably go for the mk111 titanic can i use the 250 amp that is without bass boost or is the bass boost worth having,the titanic is 4ohm is this not a problem,just downloaded the unibox how will i know if the box dimensions are correct if they wern't in winISD

[GaryG]

Here's my opinion.

If I were in your position I would want to get this right the first time round and not have to upgrade anything at a later date as a result of learning something half way along.

I've got through 5 plate amps, a couple of Shiva's, a couple of Tempests (well I did have 4, but never got around to using them all at once) and I'm still not satisfied, although I'm pretty close now, just one more upgrade to go(yeah right!).

I would suggest you go for this amp:
http://www.partsexpress.com/pe/showd...D=124777&DID=7

for use with the MKIII Titanic. That way you can be sure you're not going to run out of steam. It will work out at around the same overall cost ~ £350 all in. Another advantage is, that amp has a parametric equaliser on the front panel so after you've designed around a flat response you can give it a bit of a tweak to suit your taste.

The important part of the cabinet is the volume, you can have whatever dimensions you want to reach the desired volume (180l f3 ~ 20hz), remember the driver, amp and bracing will take up some of that volume so you need to include that in your calculation.

Btw, hope you did a good job of building that extension, a ported sub with those parts is going to put it to the test!

[panny300]

just looked on a site that i found earlier (loudspeaker 101) it has some calculators just thught i would give them a try using the titanic driver specs, put in QTS 0f .38 VAS of 7.79hz FS of 19.93hz
it spat out VB of 7.27cuft F3 20hz FB 20hz close to yours, put some data for the port using the FB 20hz and came out with a min diam of 7.37" min area of 42.67" and a lengh of 40" how do you fit that into the enclosure.

[GaryG]

Build a big cabinet!

http://www.geocities.com/manurescape...l?982993304980


or bend the port around the cabinet, can't find the example I'm looking for at the moment, will post a link when I've found it.

edit:

Found it:
http://www.hometheaterhifi.com/volum...tember-99.html