Building some speakers - Anyone done it?
Discussion
Ambleton said:
Thanks for the input crackie, they won't be "listening" loudspeakers, only playing low level background music whilst sat out in the garden having a bbq etc.
Even so, if there isn't enough bass I'll look at a small sub like the one you've suggested. There are a few 3d printed isobaric designs too which look neat. Any thoughts/impressions on any of those?
Isobaric loading can work very well but all bass loading techniques have their pros and cons; isobaric designs can play deep in a relatively small cabinet but designs are more costly because they must use 2 or more drivers. It's always a trade off. I've not developed any commercial isobaric designs myself though.Even so, if there isn't enough bass I'll look at a small sub like the one you've suggested. There are a few 3d printed isobaric designs too which look neat. Any thoughts/impressions on any of those?
Edited by Ambleton on Sunday 12th June 23:32
I didn't have time to look at the measured results but the Hexibase designs look pretty well resolved.......... If going down the 2.1 sub plus pair of satellites route, you may be interested on one of these; I use one to drive the sub / sat system in my kitchen. https://www.amazon.co.uk/RUIZHI-Subwoofer-Amplifie...
My experience has been with 'conventional' sealed, ported, quarter wave and transmission line subs. Back in 2003 I developed a slimline sub, using a 4" driver, for Toshiba UK's TV division. It used two separate transmission lines similar to the Thingiverse designs above.
I downloaded the 4" Backhorn design and set about butchering it for my requirements.
- modified to accept my driver better
- fixings for the drive unit are more substantial (and replacable)
- created a grille which can be bolted in place to stop critters going into the horn
- changed the side panel so it properly overlaps for better bonding and seal
- put two x M5 captive nuts and mount on the back for wall mounts I've acquired
- modified so the exit for the cable so it now a waterproof gland.
Mounts I have bought are a pair of B-Tech 332.
I intend to mount them landscape, hence the bracket orientation.
- modified to accept my driver better
- fixings for the drive unit are more substantial (and replacable)
- created a grille which can be bolted in place to stop critters going into the horn
- changed the side panel so it properly overlaps for better bonding and seal
- put two x M5 captive nuts and mount on the back for wall mounts I've acquired
- modified so the exit for the cable so it now a waterproof gland.
Mounts I have bought are a pair of B-Tech 332.
I intend to mount them landscape, hence the bracket orientation.
Edited by Ambleton on Thursday 16th June 17:44
Ambleton said:
I downloaded the 4" Backhorn design and set about butchering it for my requirements.
- modified to accept my driver better
- fixings for the drive unit are more substantial (and replacable)
- created a grille which can be bolted in place to stop critters going into the horn
- changed the side panel so it properly overlaps for better bonding and seal
- put two x M5 captive nuts and mount on the back for wall mounts I've acquired
- modified so the exit for the cable so it now a waterproof gland.
Mounts I have bought are a pair of B-Tech 332.
I intend to mount them landscape, hence the bracket orientation.
Good work Ambleton........looking forward to seeing how things progress - modified to accept my driver better
- fixings for the drive unit are more substantial (and replacable)
- created a grille which can be bolted in place to stop critters going into the horn
- changed the side panel so it properly overlaps for better bonding and seal
- put two x M5 captive nuts and mount on the back for wall mounts I've acquired
- modified so the exit for the cable so it now a waterproof gland.
Mounts I have bought are a pair of B-Tech 332.
I intend to mount them landscape, hence the bracket orientation.
Edited by Ambleton on Thursday 16th June 17:44
Final part came off the printer today.
I've gone through just over 2kgs of black filament (yikes). I ran out of black so the grille bits are red.
Speaker bodies were about 850g and the side panels about 170g.
Each body was about 27hrs and the sides about 6hrs each.
Got the last bits of assembling to do. Amplifier board is now in the country and should turn up this week and I can try it all out.
I've gone through just over 2kgs of black filament (yikes). I ran out of black so the grille bits are red.
Speaker bodies were about 850g and the side panels about 170g.
Each body was about 27hrs and the sides about 6hrs each.
Got the last bits of assembling to do. Amplifier board is now in the country and should turn up this week and I can try it all out.
Hi, still no amplifier yet! Apparently it's been in the UK since the 19th. Fingers crossed this week.
I ordered it on the 9th June and its come from China. Anything <20days I think is good going. ~30 days acceptable and >40 is a bit of a piss take.
I cant even hook them up to my main system easily as it's all neatly boxed in with no exposed wiring. (We have a house rabbit).
I ordered it on the 9th June and its come from China. Anything <20days I think is good going. ~30 days acceptable and >40 is a bit of a piss take.
I cant even hook them up to my main system easily as it's all neatly boxed in with no exposed wiring. (We have a house rabbit).
Amp turned up in the post this morning.
You can imagine my excitement for hooking it all up and testing...
What a disappointment.... Terrible.
The problem is the drivers but not sure if I should throw any more money at the project or not.
Will hook the amp up to some other speakers I have just to make sure that's all good.
If anyone (I'm looking at crakie in particular but anyone else with any knowledge please do chip in) can recomend a 4" full range driver that won't break the bank then I'm all ears.
You can imagine my excitement for hooking it all up and testing...
What a disappointment.... Terrible.
The problem is the drivers but not sure if I should throw any more money at the project or not.
Will hook the amp up to some other speakers I have just to make sure that's all good.
If anyone (I'm looking at crakie in particular but anyone else with any knowledge please do chip in) can recomend a 4" full range driver that won't break the bank then I'm all ears.
Ambleton said:
Amp turned up in the post this morning.
You can imagine my excitement for hooking it all up and testing...
What a disappointment.... Terrible.
The problem is the drivers but not sure if I should throw any more money at the project or not.
Will hook the amp up to some other speakers I have just to make sure that's all good.
If anyone (I'm looking at crakie in particular but anyone else with any knowledge please do chip in) can recomend a 4" full range driver that won't break the bank then I'm all ears.
I did mention earlier in the thread that they won't sound much good without some DSP applied.You can imagine my excitement for hooking it all up and testing...
What a disappointment.... Terrible.
The problem is the drivers but not sure if I should throw any more money at the project or not.
Will hook the amp up to some other speakers I have just to make sure that's all good.
If anyone (I'm looking at crakie in particular but anyone else with any knowledge please do chip in) can recomend a 4" full range driver that won't break the bank then I'm all ears.
All (very) small speakers (drivers) need DSP to sound their best, especially a design like the ones you have built, with the pseudo transmission line.
You might try a 4" BMR however I suspect you'll still be disappointed.
Well they've been on for about an hour and already they seem better.
I think it's maybe 60/40 of the drivers bedding in vs me getting used to them.
I need to line the primary chamber with something as they're very harsh/boomy and quite tiring at louder volumes.
Maybe it's a little unfair comparing them to my B&W P7 headphones I use pretty much all day every day.
The sharp Ts and Ss on vocals and dialogue are lost though... not sure I can live with that. Bass seems to crackle and be not overly reactive.
I think it's maybe 60/40 of the drivers bedding in vs me getting used to them.
I need to line the primary chamber with something as they're very harsh/boomy and quite tiring at louder volumes.
Maybe it's a little unfair comparing them to my B&W P7 headphones I use pretty much all day every day.
The sharp Ts and Ss on vocals and dialogue are lost though... not sure I can live with that. Bass seems to crackle and be not overly reactive.
Crackling bass suggests the driver is being over driven, and hitting the end stops - does it crackle all the time, or just at higher volumes?
Car speakers are typically optimised for a large surface area, which you don't have - even with the long port / TL.
Which Class D amp do you have? One of the TPA3116D modules?
Car speakers are typically optimised for a large surface area, which you don't have - even with the long port / TL.
Which Class D amp do you have? One of the TPA3116D modules?
TonyRPH said:
Crackling bass suggests the driver is being over driven, and hitting the end stops - does it crackle all the time, or just at higher volumes?
Car speakers are typically optimised for a large surface area, which you don't have - even with the long port / TL.
Which Class D amp do you have? One of the TPA3116D modules?
Yes, just at higher volumes. Car speakers are typically optimised for a large surface area, which you don't have - even with the long port / TL.
Which Class D amp do you have? One of the TPA3116D modules?
The amp I have is one of these-
https://www.ebay.co.uk/itm/175298770133?mkcid=16&a...
ZK-502MT
Spent the last 30mins finding the best balance on trebble/bass. Think I've now found the "best" place but might tweak it a little more.
With a 12v PSU you are going to be getting about 7 to 10 12 to 15 useable watts (into 4 ohms) before audible distortion sets in.
Cranking up the bass will reduce headroom considerably, so although you may get some bass, it will likely be distorting at anything above moderate listening levels.
A higher voltage would possibly help.
Bluetooth may also be a limiting factor here.
EDIT: Apologies on the power - I was quoting figures in to 8 ohms. Now corrected.
Cranking up the bass will reduce headroom considerably, so although you may get some bass, it will likely be distorting at anything above moderate listening levels.
A higher voltage would possibly help.
Bluetooth may also be a limiting factor here.
EDIT: Apologies on the power - I was quoting figures in to 8 ohms. Now corrected.
Edited by TonyRPH on Thursday 30th June 15:15
Ambleton said:
Amp turned up in the post this morning.
You can imagine my excitement for hooking it all up and testing...
What a disappointment.... Terrible.
The problem is the drivers but not sure if I should throw any more money at the project or not.
Will hook the amp up to some other speakers I have just to make sure that's all good.
If anyone (I'm looking at crakie in particular but anyone else with any knowledge please do chip in) can recomend a 4" full range driver that won't break the bank then I'm all ears.
My apologies, I've only just revisited the thread.You can imagine my excitement for hooking it all up and testing...
What a disappointment.... Terrible.
The problem is the drivers but not sure if I should throw any more money at the project or not.
Will hook the amp up to some other speakers I have just to make sure that's all good.
If anyone (I'm looking at crakie in particular but anyone else with any knowledge please do chip in) can recomend a 4" full range driver that won't break the bank then I'm all ears.
On your original post, you posted a link to some Thingiverse and said "Looks like reasonable reviews with quite a few builds..." Digging a little showed the driver they used was this Visaton unit. https://www.visaton.de/en/products/drivers/fullran... It has a very high QTS ( Total damping figure.
How did you select the JBL 4" unit you mentioned you were using? I couldn't see any parameters on the JBL site about their model number 424 driver. It might be that the JBL has parameters ( Magnet strength & cone surround compliance ) that aren't ideally suited to the cabinet type and/or the cabinet volume.
The 4 ohm and 8 ohm versions of the BMR linked earlier in the thread will work. So will the SEAS 4 inch unit from the bowl project ( I've named them Eye pods
) The SEAS units are relatively expensive compared to the BMR's.........which work very well as full range drivers even though they only used for the top end on the pipe speakers. Years ago I heard some Magnepan MMGs and subsequently have been committed to `open baffle' designs. Lots of people with better prose than me, but they sound `life like'. They can be very easy and cheap to build with money being spent on drivers rather than furniture finish. IMO OB speakers using ribbon tweeters are special.
There are compromises but IMO these are more than worth the trouble:
1. They need to be well away from any sound reflecting surface. This is to give enough time separation between the front wave and the reflected rear waves so that your brain can identify these as different and not just a scrambled mess. Rule of thumb is about 1m minimum. So you need some space.
2. They are not good at `impactful bass' (lack of enclosure derived resonance enhancement), and they are limited in bass extension to lower frequencies (due to `wrap around' cancellation of the front and rear waves). If unaddressed this can result in a `thin' sound BUT add a good amount of driver area and some electronic bass boosting and you can regain the bass presence and the end result is untainted by boxes.
For bass beyond that which originates from `musical instruments' take a look at this...
https://www.first
tt.com/pdf/art_elpipeo.pdf
Given access to unfinished roof space, these could be laid horizontally and would be ideal to combine with OB design main speakers.
You also have an opportunity to experiment with infinite baffle speakers and just mount the drivers in the wall and losing the rear wave into the attic space. You would perhaps lose some of the realism of a OB dipole, but equally you may gain more by getting rid of the limitations imposed by finite enclosures: Assuming your attic has a lot of insulation lying around, it will soak up the vibrations off the back of the driver and the `effectively infinite' enclosure volume will leave the driver free to move back and forth unlimited by enclosure pressure changes.
There are compromises but IMO these are more than worth the trouble:
1. They need to be well away from any sound reflecting surface. This is to give enough time separation between the front wave and the reflected rear waves so that your brain can identify these as different and not just a scrambled mess. Rule of thumb is about 1m minimum. So you need some space.
2. They are not good at `impactful bass' (lack of enclosure derived resonance enhancement), and they are limited in bass extension to lower frequencies (due to `wrap around' cancellation of the front and rear waves). If unaddressed this can result in a `thin' sound BUT add a good amount of driver area and some electronic bass boosting and you can regain the bass presence and the end result is untainted by boxes.
For bass beyond that which originates from `musical instruments' take a look at this...
https://www.first
tt.com/pdf/art_elpipeo.pdfGiven access to unfinished roof space, these could be laid horizontally and would be ideal to combine with OB design main speakers.
You also have an opportunity to experiment with infinite baffle speakers and just mount the drivers in the wall and losing the rear wave into the attic space. You would perhaps lose some of the realism of a OB dipole, but equally you may gain more by getting rid of the limitations imposed by finite enclosures: Assuming your attic has a lot of insulation lying around, it will soak up the vibrations off the back of the driver and the `effectively infinite' enclosure volume will leave the driver free to move back and forth unlimited by enclosure pressure changes.
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