Hi there,
This will be my first try to make my own speakers.
So I decided to keep it as simple as possible.
They are supposed to be desktop friendly, so I was thinking about 5-6 liters volume.
I decided for the W4-2142 because it is well suited for a small bass reflex and has high sensitivity.
I wanted to ask if someone has a link to an especially detailed and high quality finish instruction for a small
bass reflex?
I plan not to use any audiofrequency rejector circuits.
I have to say that I plan to run them without an traditional amp directly from my Chord Mojo witch has a total THD of 0.00017% @3v.
Does the tiny THD allow a design without any audio frequency rejector circuit?
Any helpful input is highly welcome
Cheers
This will be my first try to make my own speakers.
So I decided to keep it as simple as possible.
They are supposed to be desktop friendly, so I was thinking about 5-6 liters volume.
I decided for the W4-2142 because it is well suited for a small bass reflex and has high sensitivity.
I wanted to ask if someone has a link to an especially detailed and high quality finish instruction for a small
bass reflex?
I plan not to use any audiofrequency rejector circuits.
I have to say that I plan to run them without an traditional amp directly from my Chord Mojo witch has a total THD of 0.00017% @3v.
Does the tiny THD allow a design without any audio frequency rejector circuit?
Any helpful input is highly welcome
Cheers
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Not sure what you're asking as far as a link to finish instruction, but as far as using your Chord Mojo... Isn't that a headphone amp? If so, you'll need something different to run your speakers. Something like this should work well:
Lepai LP-2020TI Digital Hi-Fi Audio Mini Amplifier with Power Supply
If I'm off-base I apologize.
Mike
Lepai LP-2020TI Digital Hi-Fi Audio Mini Amplifier with Power Supply
If I'm off-base I apologize.
Mike
Hey Mike,
Thanks for your reply!
Yes the Mojo is made for headphone use.
It's not an amp but a DAC with variable line out and only one vera simple analog stage.
It can push 720mw into 8 ohm, so I figured I 'll give it a try
for desktop duty...
I read of people, who where driving even less sensitive speakers directly from Mojo or Hugo (which has the same output stage) and where happy listening to medium volume...
As for the instructions, I was thinking of an especially well suited guide for first timers 🙂 ... But I guess I can work with what I got.
Any further input appreciated 😉
Cheers
Thanks for your reply!
Yes the Mojo is made for headphone use.
It's not an amp but a DAC with variable line out and only one vera simple analog stage.
It can push 720mw into 8 ohm, so I figured I 'll give it a try
for desktop duty...
I read of people, who where driving even less sensitive speakers directly from Mojo or Hugo (which has the same output stage) and where happy listening to medium volume...
As for the instructions, I was thinking of an especially well suited guide for first timers 🙂 ... But I guess I can work with what I got.
Any further input appreciated 😉
Cheers
If you have the resources to cut wood straight and drill or cut a mounting hole, building an enclosure can be pretty straight-forward. A Google search might yield some results for a project. If not, Parts Express ran the driver in Bass Box Pro and came up with a 1.78 liter sealed box (f3 150Hz) or a 2.83 liter vented box (f3 88Hz). Others will probably have more ideas. If you don't have the resources to do any woodworking, there might be someone near you or a local carpenter who can cut the wood for you.
You can also download Win ISD Pro (LinearTeam) and run the numbers to model your own box. There are tutorials available if you're unfamiliar with WinISD.
Mike
You can also download Win ISD Pro (LinearTeam) and run the numbers to model your own box. There are tutorials available if you're unfamiliar with WinISD.
Mike
I'm with Mike regarding the Lepai amp because I suspect these TB's W4 don't have enough bass...you may need the tone control...depending on the music you listen to. I have both the W3's and the W5's. The smaller W3 (87 db) don't much bass at all below say 90 hz ( as expected)... I was also disappointed with the SPL. Seems less than what manufacturer quotes on spec. The larger w5 are great in that respect and my ears detect the higher (90 db) sensitivity ...sound very good with just a few watts. I hope the w4's work better for you than the w3's which I'll be experimenting in a FAST configuration in near future.
Seems to me the only way to get best out of these TB W's is to build some form of transmission line enclosure. Unfortunately I haven't seen one yet for the W4. However that is beyond beginner design and not as simple as bass reflex and boxes are much larger..maybe in future if it is of interest and some one here reveals plan for details for such enclosures such as TABAQ (tang band quarter line transmission line) or Karlsonator enclosure.
If you think the mid - high frequencies are too much, you may need BSC circuit to tame down. Baffle step compensation (BSC) is just an inductor and resistor paralleled in series with the speaker... Usually 1 mh and a few ohms resistor. Regardless let us know how these W4's work for you.
Seems to me the only way to get best out of these TB W's is to build some form of transmission line enclosure. Unfortunately I haven't seen one yet for the W4. However that is beyond beginner design and not as simple as bass reflex and boxes are much larger..maybe in future if it is of interest and some one here reveals plan for details for such enclosures such as TABAQ (tang band quarter line transmission line) or Karlsonator enclosure.
If you think the mid - high frequencies are too much, you may need BSC circuit to tame down. Baffle step compensation (BSC) is just an inductor and resistor paralleled in series with the speaker... Usually 1 mh and a few ohms resistor. Regardless let us know how these W4's work for you.
Thanks for the input!
@mike:
I think about letting a friend do the wood work, since he is a carpenter, but has never build a speaker box before.
So I hoped for a very detailed instruction, so there won't be any mistakes in Damping.
Would it make sense to use a strong zipper style wood connection (see picture).
Would 20mm MDF be suited or should I spend a little more for better construction material?
I think I will go with a box slightly bigger than 5 liters to get a better bass response (supposed to be f3 58HZ).
@revelator
Thanks for the insight on the related TB drivers. I hope the W4-2142 will give a bass response close to specs.
Since my approach is rather unusual I will have to try and see.
If the result won't satisfy I can still add BSC... and maybe even an amp, but I don't want anything to interfere with the Mojo magic, if possible. 😀
will keep you updated!
Cheers
@mike:
I think about letting a friend do the wood work, since he is a carpenter, but has never build a speaker box before.
So I hoped for a very detailed instruction, so there won't be any mistakes in Damping.
Would it make sense to use a strong zipper style wood connection (see picture).
Would 20mm MDF be suited or should I spend a little more for better construction material?
An externally hosted image should be here but it was not working when we last tested it.
I think I will go with a box slightly bigger than 5 liters to get a better bass response (supposed to be f3 58HZ).
@revelator
Thanks for the insight on the related TB drivers. I hope the W4-2142 will give a bass response close to specs.
Since my approach is rather unusual I will have to try and see.
If the result won't satisfy I can still add BSC... and maybe even an amp, but I don't want anything to interfere with the Mojo magic, if possible. 😀
will keep you updated!
Cheers
The type of joint you have pictured will work well as long as it is air-tight. I usually run a bead of glue or silicone sealant along all the internal seams. 45 degree mitered joints are very popular as well. The more gluing surface, the better. The box should be air-tight other than the port, if you use a port. There should be no issues with 20 mm MDF. Otherwise, some things to keep in mind are the front baffle width can affect the bass and you should NOT make the box symmetrical. The golden ratio is a good starting point for your box dimensions (.6 X 1 X 1.6). Depending how close to the wall you plan to use the speakers, you might want to look into baffle step compensation (BSC). The closer to a rear wall, the less chance you'll need any BSC. You can find a lot of info about BSC with a Google search.
This page has a lot of good software tools, including box modeling. I believe you can model the baffle size as well.
Jeff Bagby's Software Page
Mike
This page has a lot of good software tools, including box modeling. I believe you can model the baffle size as well.
Jeff Bagby's Software Page
Mike
You're using a 4" driver in a desktop system. Simple butt joints will be fine. Use plenty of glue, and then run some more around the inside to make sure its airtight.
12mm MDF will be more than enough for this, too. 20mm MDF will be overkill in strength, and might make it more difficult to mount the drivers.
FWIW I used 15mm ply to build some high-power 2x10" PA speakers. Even the 21" build was only 18mm ply. Both had lots of internal bracing, though.
Chris
12mm MDF will be more than enough for this, too. 20mm MDF will be overkill in strength, and might make it more difficult to mount the drivers.
FWIW I used 15mm ply to build some high-power 2x10" PA speakers. Even the 21" build was only 18mm ply. Both had lots of internal bracing, though.
Chris
Thanks again Mike,
I found this site Internal Standing Wave Calculator for Loudspeaker Enclosures and Rooms
It allows to apply the golden ratio backwards from volume.
For 5 Liter I get a rounded 220mm x 135mm x 170mm
with factor of 0.5 for golden ratio.
The bass tube is supposed to be 35mm diameter and 135mm long.
could I install the bass tube in the rear panel, or is the 35mm clearance problematic?
this is supposed to give F3 58HZ according to this shop
Tang Band
when I use 45 degree mitered connections, should I also use mitered connections on front and back panel?
@Chris
Maybe 20mm is overkill, I will think about the build material again.
Hope this works out 🙂
Cheers
I found this site Internal Standing Wave Calculator for Loudspeaker Enclosures and Rooms
It allows to apply the golden ratio backwards from volume.
For 5 Liter I get a rounded 220mm x 135mm x 170mm
with factor of 0.5 for golden ratio.
The bass tube is supposed to be 35mm diameter and 135mm long.
could I install the bass tube in the rear panel, or is the 35mm clearance problematic?
this is supposed to give F3 58HZ according to this shop
Tang Band
when I use 45 degree mitered connections, should I also use mitered connections on front and back panel?
@Chris
Maybe 20mm is overkill, I will think about the build material again.
Hope this works out 🙂
Cheers
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The port can go on the front or the rear. It's pretty much personal preference. You need to have room behind the speaker for the vent to do what it does; at least as far away from the wall as the diameter of the vent. Miters on the front and back are good, but not absolutely necessary. Butt-joints all around are fine too, as long as they're air-tight. And with MDF, butt-joints leave the ends exposed, which can create an issue if you try to use paint to finish the speakers. If you use veneer, it shouldn't matter. Regular butt-joints are fine as long as they're air-tight. You might want to add a few internal braces if you go to 12mm MDF. That's usually the route most people take.
so the 35mm diameter equaling the clearance of the bass tube to the front wall (when installed facing backwords) should work.
Considering that the speakers will likely be placed close to a wall would it be better to install the tube in the top cover?
Would a passive radiator (or two) installed to the side wall instead of the bass tube give better bass response and presentation when close to a wall?
I checked measures of the driver and see no problem with a strong material, so I will likely go with 18mm MDF and mitered connections.
Cheers
Considering that the speakers will likely be placed close to a wall would it be better to install the tube in the top cover?
Would a passive radiator (or two) installed to the side wall instead of the bass tube give better bass response and presentation when close to a wall?
I checked measures of the driver and see no problem with a strong material, so I will likely go with 18mm MDF and mitered connections.
Cheers
As far as I know, you should be fine. You always can put a 90 degree bend in the vent to ensure you have the right amount of clearance. I wouldn't put the vent in the top simply because it would be pretty easy for something to fall or be dropped inside the speaker. One thing you want to keep in mind is to NOT place the vent directly behind the woofer. I've seen and heard speakers with the tube on the outside of the enclosure. WinISD will let you model with passive radiators. I've never used them in a build, so I can't honestly answer your questions about them.
Mike
Mike
Thanks Mike,
I think I will stick with the bass reflex, for now.
Since my buddy will be away for a week and I found fitting MDF in the garage, I might try this myself 🙂
I will also try a different driver first.
I found some NOS Multicel MS-115, which are about the same size, are also suggested for a 5l bass reflex and have 94(!) db sensitivity.
So I think I am about ready... with a little luck the drivers arrive tomorrow.
Cheers
I think I will stick with the bass reflex, for now.
Since my buddy will be away for a week and I found fitting MDF in the garage, I might try this myself 🙂
I will also try a different driver first.
I found some NOS Multicel MS-115, which are about the same size, are also suggested for a 5l bass reflex and have 94(!) db sensitivity.
So I think I am about ready... with a little luck the drivers arrive tomorrow.
Cheers
Sounds like a good idea. And remember, this is just your first one. If there are things you don't like about a speaker project, there are always ways to tweak it. There are plenty of drivers out there that a guy can experiment with too, some very expensive and some very inexpensive. Cost doesn't always reflect the sound quality of a speaker.
Have fun!
Mike
Have fun!
Mike
Thanks for the encouraging words 😉
I hope it will work out, like planned.
And if not, I will remember to use some tweaks...
I will post Updates soon.
Cheers
I hope it will work out, like planned.
And if not, I will remember to use some tweaks...
I will post Updates soon.
Cheers
Hey there,
A little update:
The drivers arrived and I put them in my old hifi boxes
which had the correct measurements and even the holes
where in the right place... So I went the lazy route just to have a 'proof of concept'
I ripped apart a hosa 3.5mm to dual 6.3mm cable and connected it to the drivers and put them in the boxes.
I have to say it was a pleasant surprise... Volume won't be an issue with a few dB sensitivity less.
I can easily fill a 15m2 room with sound.
Since the 'Boxes' I used for the proof of concept aren't air tight... I mean not at all its not easy to evaluate the quality of the sound.
What I can say is that they sound best with music with high dynamic range. Listening to the first tracks of the New Chilli Peppers album in 24/96 showed hints of magic, as well as a Meatloaf EAC Rip.
So next week my Buddy will hopefully build the boxes and I can get a better climps of what the combo is capable of.
Any tipps on weather or not to damp the boxes?
I have plenty of Sonofil on hand...
One more question concerning the cabling. In my special cenario of driving the boxes with 720mw max what AWG value would you suggest?
I am super excited to get a decent enclosure and can't wait to get this going on.
Will post some pics of the whole combo when I have the decent boxes.
Cheers
A little update:
The drivers arrived and I put them in my old hifi boxes
which had the correct measurements and even the holes
where in the right place... So I went the lazy route just to have a 'proof of concept'
I ripped apart a hosa 3.5mm to dual 6.3mm cable and connected it to the drivers and put them in the boxes.
I have to say it was a pleasant surprise... Volume won't be an issue with a few dB sensitivity less.
I can easily fill a 15m2 room with sound.
Since the 'Boxes' I used for the proof of concept aren't air tight... I mean not at all its not easy to evaluate the quality of the sound.
What I can say is that they sound best with music with high dynamic range. Listening to the first tracks of the New Chilli Peppers album in 24/96 showed hints of magic, as well as a Meatloaf EAC Rip.
So next week my Buddy will hopefully build the boxes and I can get a better climps of what the combo is capable of.
Any tipps on weather or not to damp the boxes?
I have plenty of Sonofil on hand...
One more question concerning the cabling. In my special cenario of driving the boxes with 720mw max what AWG value would you suggest?
I am super excited to get a decent enclosure and can't wait to get this going on.
Will post some pics of the whole combo when I have the decent boxes.
Cheers
It is a good custom to damp at least the wall directly behind the speaker but it probably will not play big role for low listening levels. Overstuffing can cause loss of sensitivity but you can experiment having such a simple box: try, listen, take out the speaker, change the stuffing and listen again. Be careful not to destroy the mounting holes, tho... ;-)
Do not orientate on the 720mW but on the max power of the speaker - you (or someone else) may want to run the box in another setup in the future. The driver has a rated power 25W (although I do not think you will use that much in the small box). I would take some rest of a stranded wire you have at hand (Litze 2x0,5mm2 will do). Wish you a lot of fun with the build and listening...
Mike
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