Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Multi-Way Conventional loudspeakers with crossovers

Bluetooth speaker build... more bass!!!
Bluetooth speaker build... more bass!!!
Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Thread Tools Search this Thread
Old 10th December 2017, 02:51 AM   #1
Hayden is offline Hayden  Australia
diyAudio Member
Join Date: Aug 2004
Location: Mackay Australia
Default Bluetooth speaker build... more bass!!!

I have dug up an old project that I got sidetracked on ages ago which is a bluetooth speaker build.
I'm having dramas with getting the appropriate bass out of it.... yes yes I know the box volume isn't correct for the drivers because compact is everything..... for me anyway but a little more bass would be great!!!!!
Any tips or tricks?
It's running a pair of Dayton Audio nd91-4 full range drivers in the same chamber (separate to the top drivers) for the low end (the 2.1 amp crossover works wonders ) in a sealed 6mm MDF enclosure....Amp power is not an issue too

The chamber of the low end drivers are 180x95x85mm roughly... which is about 1453.5cm3 about 1.4L not including driver displacement.
I have tried porting the box and I do get a bit more bottom end BUT then It can only be turned up like half volume as it reaches excursion limits of the drivers. Sealed I can turn it up louder as the drivers are more controlled by the sealed box but it is too punchy and lacks the low notes. **can't expect to much bass out of little speakers **

I know sealed is a bit more punchy but would a passive radiator work??
would ditching 2 drivers for one be better? as it halves the cone area but then it like doubles the box volume for that one driver
Any input would be greatly appreciated to finish this project

P.S. I do have the full spec sheet of the drivers if needed


Click the image to open in full size.
  Reply With Quote
Old 10th December 2017, 05:22 AM   #2
Jerms is offline Jerms  United Kingdom
diyAudio Member
Join Date: Jun 2015
Location: High Wycombe, Bucks, UK.
How loud does it have to be?

The ND91s ported will do the job on their own in a small(ish) enclosure but we're probably still talking 4 litres for the pair. Can be modelled in WinISD. Between 1.5L-2.0L volume they'll drop into the 60-70Hz range.

Have you seem Paul Carmody's Sprite? The 91s will not drop as low but require much smaller enclosure.
  Reply With Quote
Old 10th December 2017, 06:14 AM   #3
Nico Ras is offline Nico Ras  South Africa
diyAudio Member
Nico Ras's Avatar
Join Date: Nov 2005
Location: East Coast of South Africa
Go look at the Linkwitz equalizer on Rod Eliot's site. It will solve your problem.
ESP - The Linkwitz Transform Circuit
Kindest regards
  Reply With Quote
Old 10th December 2017, 01:51 PM   #4
Hayden is offline Hayden  Australia
diyAudio Member
Join Date: Aug 2004
Location: Mackay Australia
Thank you so much for your help guys!! I did look at those links and builds and they did look very interesting... I will use those links for future projects

I think I have solved the problem..... believe it or not I stuck 4 coins on each driver cone and man did it make a difference!!!!! I mean the bass was a lot deeper/natural and it stopped it sounding like "beating a cardboard box" sound. The speaker box nearly vibrated off my test bench haha I suppose with the added weight it stores/releases more energy.
it's a bit hard to notice the difference on camera but I'll try and post a video.
P.S. I hope the added weight doesn't wreck the speakers haha
  Reply With Quote
Old 26th July 2018, 07:32 PM   #5
SNimmer is offline SNimmer
diyAudio Member
Join Date: Jul 2018
along the same lines of this thread but this is unchartered territory for me and I simply cannot use the info above to feel comfortable moving forward. I have a fairly heavy mdf old center channel speaker with (3.5") old paper drivers in it. plans are to add a bluetooth amp, battery pack, and upgrade the drivers. So far, I am leaning towards (2) Dayton ND91-8 drivers and the expectation that i need passive radiators to balance the bass.

Here are what I believe to be the needed pieces of info if one of you could point me in the right direction for radiator choice.

single chamber
inside dimensions are 11.25 x 3.75 x 5.0 inches which i have calculated to be .122 cubic ft or converted to 3.45 liters (so about 1.725 liters per driver). Can anyone assist with info on choosing the appropriate passive radiator? Thank you.
  Reply With Quote


Bluetooth speaker build... more bass!!!Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
First Bluetooth Speaker Build Tips bellamym Class D 6 17th September 2017 12:42 PM
"Portable" bluetooth speaker build advice Sonicfury405 Multi-Way 17 16th March 2017 08:26 AM
New Bass Cab Speaker Build dbhokie Multi-Way 38 13th September 2015 01:03 AM
Bluetooth Speaker (Build Log) MatthewP Everything Else 0 4th November 2013 08:39 AM
bass cabinet build two 18" speaker.. help szgabor Multi-Way 3 7th August 2004 01:23 AM

New To Site? Need Help?

All times are GMT. The time now is 02:28 AM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.00%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright ©1999-2019 diyAudio