Hi eveyone,
I'm trying to design & build a pair of 3-way speakers, using the AJ Sealed cabinet calculator program (based on the Golden Ratio). (www.ajdesigner.com)
It asks for the Qts, Qes, Fs, Vas, PMax, diameter and Xmax of the speaker driver, leaving the Qtc for you to choose (I've read 0.707 is a good number).
For my Monacor bass drivers, it comes up with an interesting size, which I'm happy with.
But for the mid driver (which can also be used as a bass driver in a 2-way bookshelf speaker), the cabinet size it comes up with is very small, only marginally bigger than the actual driver unit!
I have all the parameters it wants from the Monacor data sheet, so I can only think that this driver needs an incredibly small cabinet.
But it seems very odd for it to be so small.
I'm going to have the mid cabinet built separately and attached to the top of the bass cabinet, and employ time alignment by having it receeded slightly (c.1 5/8 inch) back from the edge of the bass cabinet.
I used to own a pair of B&W DM-6 speakers (the 'pregnant droid' speakers!), and loved the fact that it had the mid driver recessed back from the bass, and the tweeter recessed back again from the mid driver, to achieve correct time alignment.
I thought I'd try and incorporate the same idea in my speakers. It won't do any harm in trying.
I'm using the measurements from the very back of each driver, as it's the closest I can see to measuring to the centre of the magnet, which I believe is the actual axis I should be basing such calculations on.
I've read that each side panel should be internally braced to avoid resonances.
What exactly does this look like?
Do I just glue diagonal strips of wood on each internal side?
I'm thinking of using oak plywood, as it's readily available from a local DIY store.
I've read birch veneer cabinet grade plywood is preferable, for which I'll look.
I was considering getting a brad nailer to assdist in the construction, but have read of people using wood / deck screws.
I built 2 GhettoBlasters a few years ago using the Golden Ratio, 1/2 inch oak plywood & MDF (one each), old car radio units, 6x9 speakers and car subwoofer amps & drivers.
I used deck screws for the construction, along with carpenter's glue, but found it very time consuming drilling all the pilot then clearance holes, and thought that if professionally built cabinets are constructed using staples / nails, then surely it must be just as good as screws and much faster..?
They sound great, by the way, which is why I'm attempting this speaker build.
The speakers with be 3-way, and will be matched to a Bassworks 2x12 front ported car subwoofer cabinet featuring 2 x 12 inch SSL "1000w" speaker drivers.
I had this running via a QSC amp recently, via a Clean Box Pro -10 to +4 dB converter, from my 2.1 stereo amp, and it sounds incredible!
So, it'll be a 4-way actively crossed over system, using a dbx DriveRack 260 speaker management system, feeding into 3 Yamaha Natural Sound stereo amps plus the QSC sub amp.
The dbx will give me stereo top & stereo mid, then mono-summed bass and mono-summed sub-bass at line level.
The Yamaha amps and Monacor drivers (all the tweeters, squakers & woofers are Monacor, to keep the sound consistent) are matched for power output / input, and all the Yamaha amps are identical (to keep the sound consistent).
My aim is to combine my experience of working with PA sound rigs, studio monitor sound systems, car and home audio Hi-Fi speaker technology and create a hybrid sound system.
I want, not just a 3-way speaker (which is a rarity in domestic Hi-Fi, and why I loved my DM-6s so much), but an ACTIVELY crossed-over time-aligned 3-way speaker, using the advantages of PA technology, then adding it to a deep and powerful sub-bass speaker unit.
The potential is quite breathtaking.
My very own personal Hi-Fi PA theatre studio monitor system.
If nothing else, it'll be a fascinating experiment into all of the fields mentioned.
And judging from my GhettoBlasters, there's every chance the system will sound pretty impressive.
Going for sealed cabinet / infinate baffle seems to give a big margin of error, and hopefully a nice, warm quality bass sound.
The Bassworks sub-bass cabinet has dealt with the ported aspect, so I don't have to consider it for the main speakers.
I know there's a lot going on here, and probably many areas of concern / issue for many of you out there.
Don't worry. I know it's a totally mad idea. But why not? It'll be a laugh! And could sound great!
I just need a bit of advice in the design of the mid cabinets and the general construction of the bass & mid cabs (the tweeters will reside above the mids in the same cabinet, but sealed off so their internal volumes don't affect each other).
I've found my Canadian Tire mitre & table saws aren't very accurate, so cutting consistently is a bit hard.
I've tried using my circular saw using a metal ruler clamped down as a straight edge guide, but this too has its issues with accuracy.
I've had no wood-working / carpentry training, and have taught myself the skills so far. Maybe not very well..!
Any advice is greatly appreciated!
Many thanks in advance - Dave
I'm trying to design & build a pair of 3-way speakers, using the AJ Sealed cabinet calculator program (based on the Golden Ratio). (www.ajdesigner.com)
It asks for the Qts, Qes, Fs, Vas, PMax, diameter and Xmax of the speaker driver, leaving the Qtc for you to choose (I've read 0.707 is a good number).
For my Monacor bass drivers, it comes up with an interesting size, which I'm happy with.
But for the mid driver (which can also be used as a bass driver in a 2-way bookshelf speaker), the cabinet size it comes up with is very small, only marginally bigger than the actual driver unit!
I have all the parameters it wants from the Monacor data sheet, so I can only think that this driver needs an incredibly small cabinet.
But it seems very odd for it to be so small.
I'm going to have the mid cabinet built separately and attached to the top of the bass cabinet, and employ time alignment by having it receeded slightly (c.1 5/8 inch) back from the edge of the bass cabinet.
I used to own a pair of B&W DM-6 speakers (the 'pregnant droid' speakers!), and loved the fact that it had the mid driver recessed back from the bass, and the tweeter recessed back again from the mid driver, to achieve correct time alignment.
I thought I'd try and incorporate the same idea in my speakers. It won't do any harm in trying.
I'm using the measurements from the very back of each driver, as it's the closest I can see to measuring to the centre of the magnet, which I believe is the actual axis I should be basing such calculations on.
I've read that each side panel should be internally braced to avoid resonances.
What exactly does this look like?
Do I just glue diagonal strips of wood on each internal side?
I'm thinking of using oak plywood, as it's readily available from a local DIY store.
I've read birch veneer cabinet grade plywood is preferable, for which I'll look.
I was considering getting a brad nailer to assdist in the construction, but have read of people using wood / deck screws.
I built 2 GhettoBlasters a few years ago using the Golden Ratio, 1/2 inch oak plywood & MDF (one each), old car radio units, 6x9 speakers and car subwoofer amps & drivers.
I used deck screws for the construction, along with carpenter's glue, but found it very time consuming drilling all the pilot then clearance holes, and thought that if professionally built cabinets are constructed using staples / nails, then surely it must be just as good as screws and much faster..?
They sound great, by the way, which is why I'm attempting this speaker build.
The speakers with be 3-way, and will be matched to a Bassworks 2x12 front ported car subwoofer cabinet featuring 2 x 12 inch SSL "1000w" speaker drivers.
I had this running via a QSC amp recently, via a Clean Box Pro -10 to +4 dB converter, from my 2.1 stereo amp, and it sounds incredible!
So, it'll be a 4-way actively crossed over system, using a dbx DriveRack 260 speaker management system, feeding into 3 Yamaha Natural Sound stereo amps plus the QSC sub amp.
The dbx will give me stereo top & stereo mid, then mono-summed bass and mono-summed sub-bass at line level.
The Yamaha amps and Monacor drivers (all the tweeters, squakers & woofers are Monacor, to keep the sound consistent) are matched for power output / input, and all the Yamaha amps are identical (to keep the sound consistent).
My aim is to combine my experience of working with PA sound rigs, studio monitor sound systems, car and home audio Hi-Fi speaker technology and create a hybrid sound system.
I want, not just a 3-way speaker (which is a rarity in domestic Hi-Fi, and why I loved my DM-6s so much), but an ACTIVELY crossed-over time-aligned 3-way speaker, using the advantages of PA technology, then adding it to a deep and powerful sub-bass speaker unit.
The potential is quite breathtaking.
My very own personal Hi-Fi PA theatre studio monitor system.
If nothing else, it'll be a fascinating experiment into all of the fields mentioned.
And judging from my GhettoBlasters, there's every chance the system will sound pretty impressive.
Going for sealed cabinet / infinate baffle seems to give a big margin of error, and hopefully a nice, warm quality bass sound.
The Bassworks sub-bass cabinet has dealt with the ported aspect, so I don't have to consider it for the main speakers.
I know there's a lot going on here, and probably many areas of concern / issue for many of you out there.
Don't worry. I know it's a totally mad idea. But why not? It'll be a laugh! And could sound great!
I just need a bit of advice in the design of the mid cabinets and the general construction of the bass & mid cabs (the tweeters will reside above the mids in the same cabinet, but sealed off so their internal volumes don't affect each other).
I've found my Canadian Tire mitre & table saws aren't very accurate, so cutting consistently is a bit hard.
I've tried using my circular saw using a metal ruler clamped down as a straight edge guide, but this too has its issues with accuracy.
I've had no wood-working / carpentry training, and have taught myself the skills so far. Maybe not very well..!
Any advice is greatly appreciated!
Many thanks in advance - Dave