Topic: Speaker DIY'ers

[vircor]

Hi!

It's not that DIYers (including me) here don't want to share info but building a speaker project is a bit complicated (tampo ka naman agad eh  ). Choices of drivers, box configs, and even materials differes from one constructor to another.

I myself only use local drivers (dai-ichi, crown, etc) and make the most out of them. But if you have access to better sounding drivers then that's better. Tell what you have and maybe I can help you. 

JojoD 

Ahahahaha! Mga sir, I'm not making tampo-tampo The reason why I did not insisted na is because naisip ko na maybe it's a trade secret. I know naman that you're all willing to share your expertise, I don't wanted lang to be makulit. Pero baka nga meron kayong mai-share na simple project na nagawa na ninyo.

Anyway, as I've said I wanted to build a 3-way floorstander. I've build loudspeakers before (by trial & error) during the college years paired it with the diy amp projects, I'm also an electronics graduate kasi before taking the path of computer & education. Kaya lang yung mga projects ko na-arbor na ng relatives and ang lalayo na nila, sigh... I miss those days.. I've lost all my copies of Electronics Enthusiasts and other lectures/notes coz of moving to a different place. Ok, enough of the reminiscin... my idea is to build a floorstander using 2- 8" woofers or 1- 10" woofer side mounted, 2-5" mids and a 1" dome tweeter the brands of which is Dai-ichi & other locally available speakers, crossovers and other parts I'll buy na lang. I will use either a 3/4" or 1" thick particle board, I have the necessary power tools and  a little carpentry skills (I hope) yun nga lang medyo gasgas na ko sa electronics. Madali lang sana but here are my concerns and hope you can help me with these:

1.) Do you guys use a method or formula in getting the internal volume of the baffle?
2.) Do you employ the aid of a certain software/program in loudspeaker design and where can I get one?
3.) How do you choose the wattage and size of each driver?
4.) How do you get the right length and size of the port in tuning the loudspeaker to a desired frequency?
5.) How can we know the efficiency of the loudspeaker we build?
6.) Does applying some paint to personalize the driver affect its performance?
7.) What store usually has the more selection of grill cloth, vinyl finishes, and other stuff?

Here are some of the sites I've visited regarding DIY Loudspeakers:
Design of Loudspeakers
Loudspeakers Principles & Theory
DIY Speaker Project

Thanks very much to all DIY Gurus!

Sir JojoD you have PM.

[vircor]

DIY projects are time consuming and can be frustrating but at the same time can be very rewarding. For those who would like to follow the path taken by our diy masters, aside from some electronics know how here are what you might check first before plunging in:
   - patience
   - guts
   - budget
   - patience
   - open mind
   - an eye for details
   - patience
   - multi-tester (a must), oscilloscope, spl meter, etc.
   - grounding strap or anti-static gloves (Statics can ruin your project, your day and your wallet)
   - pliers, long-nose, tweezer, cutter, crimping tool, etc.
   - soldering iron/gun, lead, dissoldering pump, pcb, ferric chloride, mini-drill, masking tape, etc.
   - patience
   - drills, jigsaw, files, sandpaper, etc. for metal and wood working needs
   - diff. wires & connectors, parts, components, etc.
   - others that i forgot to mention
   - did i already say lots of patience?

You may experience the following but they can definitely be avoided/minimized:
   - Makuryente
   - Mapaso
   - Masugatan
   - Malipasan ng gutom
   - Masabugan/maputukan
   - Maibato yung di mapaganang project
   - Manlumo, manlambot, ma-frustrate
   - Ano pa ba mga sir?
   - Makuryente
   - And worst, mabaliw sa di mapaganang project

But don't be afraid, one can always ask our diy masters for enlitghtenment. MABABAIT MGA YAN

[av_phile1]

A fellow I know shared this with me.
"A friend was visiting my wife and asked about the speakers I build. She answered, "Yes, Ed has spent thousands of dollars to build cheap speakers."

  Now that's a nice one.  I think it applies to building amps as well.  I had that experience in the past building a mediocre amp kit, with all the transistors I blew before finally getting it right. 

[D0Hbert]

Sir Vircor, I suggest you buy a book entitled designing and testing your loudspeakers by david weeds. Cant recall the exact title of the book, locally available din yung copy. I don't have it right now but most of your questions are answered there. They have charts  where you can base the optimum internal volume for your speakers, the appropriate capacitor values for your high pass x-over, and a lot more. May mga projects pa on speaker building, may 3-way din. Interesting read. Kahit na yung question mo about port meron din duon, pag medyo mahina bumayo, habaan ang port, pag sobrang boomy, iksiaan yung port or lakihan ang internal volume ng woofer, etc. Hope this helps.

[JojoD818]

Sir Vircor, I suggest you buy a book entitled designing and testing your loudspeakers by david weeds. Cant recall the exact title of the book, locally available din yung copy. I don't have it right now but most of your questions are answered there. They have charts  where you can base the optimum internal volume for your speakers, the appropriate capacitor values for your high pass x-over, and a lot more. May mga projects pa on speaker building, may 3-way din. Interesting read. Kahit na yung question mo about port meron din duon, pag medyo mahina bumayo, habaan ang port, pag sobrang boomy, iksiaan yung port or lakihan ang internal volume ng woofer, etc. Hope this helps.

Sir, meron ako nyan!!! Hahaha Gandang book yan. 

[tuff_u_gong]

DIY projects are time consuming and can be frustrating but at the same time can be very rewarding. For those who would like to follow the path taken by our diy masters, aside from some electronics know how here are what you might check first before plunging in:
   - patience
   - guts
   - budget
   - patience
   - open mind
   - an eye for details
   - patience
   - multi-tester (a must), oscilloscope, spl meter, etc.
   - grounding strap or anti-static gloves (Statics can ruin your project, your day and your wallet)
   - pliers, long-nose, tweezer, cutter, crimping tool, etc.
   - soldering iron/gun, lead, dissoldering pump, pcb, ferric chloride, mini-drill, masking tape, etc.
   - patience
   - drills, jigsaw, files, sandpaper, etc. for metal and wood working needs
   - diff. wires & connectors, parts, components, etc.
   - others that i forgot to mention
   - did i already say lots of patience?

You may experience the following but they can definitely be avoided/minimized:
   - Makuryente
   - Mapaso
   - Masugatan
   - Malipasan ng gutom
   - Masabugan/maputukan
   - Maibato yung di mapaganang project
   - Manlumo, manlambot, ma-frustrate
   - Ano pa ba mga sir?
   - Makuryente
   - And worst, mabaliw sa di mapaganang project

But don't be afraid, one can always ask our diy masters for enlitghtenment. MABABAIT MGA YAN

sir vircor,

among these tools, which do you need for

1)crossover designing and tweaking and
2)driver matching?

thanks!

Sir Vircor, I suggest you buy a book entitled designing and testing your loudspeakers by david weeds.

sir DOHbert,

saang bookstore meron nito sir? thanks!

[JojoD818]

Sa National Bookstore sir meron nyan. 

[D0Hbert]

One more, look for a commercial app called bassbox pro, maganda din. meron din silang program for x-over.

[av_phile1]

I believe I've come across some internet sites that have JAVA based calculators for just about every parameter you need to design a speaker, from crossover networks to box dimensions and port size.  A google search can yield many.

[vircor]

sir vircor,

among these tools, which do you need for

1)crossover designing and tweaking and
2)driver matching?

thanks!

Sir, if you're serious about crossovers/filters and speakers, you may want to have a winder/rewinder and different gauges of magnetic wires coz you'll be using them a lot. An oscilloscope would be ideal specially if you're dealing with frequencies and different wave outputs.

If you can, you may want to resort first to what is called 'reversed engineering'. Observe first the particular project you want to build like a crossover. Kung meron kang loudspeaker system sa bahay at  kung pwede baklasin ok din. Disassemble it then study the circuit of the filter/crossover. That's a good start to begin with.

You can find very valuable info here:

http://sound.westhost.com/articles.htm

Hope to be of little help. 

[vircor]

Sir Vircor, I suggest you buy a book entitled designing and testing your loudspeakers by david weeds. Cant recall the exact title of the book, locally available din yung copy. I don't have it right now but most of your questions are answered there. They have charts  where you can base the optimum internal volume for your speakers, the appropriate capacitor values for your high pass x-over, and a lot more. May mga projects pa on speaker building, may 3-way din. Interesting read. Kahit na yung question mo about port meron din duon, pag medyo mahina bumayo, habaan ang port, pag sobrang boomy, iksiaan yung port or lakihan ang internal volume ng woofer, etc. Hope this helps.

Ah... eh... ok, I'll buy a book. What book nga ba? & author? 

[tuff_u_gong]

Sir, if you're serious about crossovers/filters and speakers, you may want to have a winder/rewinder and different gauges of magnetic wires coz you'll be using them a lot. An oscilloscope would be ideal specially if you're dealing with frequencies and different wave outputs.

If you can, you may want to resort first to what is called 'reversed engineering'. Observe first the particular project you want to build like a crossover. Kung meron kang loudspeaker system sa bahay at  kung pwede baklasin ok din. Disassemble it then study the circuit of the filter/crossover. That's a good start to begin with.

You can find very valuable info here:

http://sound.westhost.com/articles.htm

Hope to be of little help. 

thanks! i guess you're right about reverse engineering. an oscilloscope and winder might be too much of an investment for a DIY newbie.

i plan to build a 2-way speaker with an 8'' bass driver with a dome tweeter. i posted a question in another forum and here is the reply i got:

The basic principles of an 8" / 1" combination with a very simple
crossover are fairly straightforward and tuning can be done by ear.

The bass unit needs a rising midrange response, and its inductor
value is misaligned to effect baffle step compensation, it then
compensates for the rising mid response, and the actual c/o
frequency is determined by the bass/ mid units roll-off.

In juggling the EQ of the bass unit baffle width is a major factor.

Usually a box of 45L to 50L tuned to 33Hz to 37Hz works well.

Sensitivity depends on the amount of baffle step compensation
built into the design, which also sets optimum placement.

i found this too technical. can you make anything of it?
have you had any experience building a speaker with such specs?
thanks!

[tuff_u_gong]

here are pictures of the crossover/filter of the speaker
i want to 'reverse engineer'.






do you think i can get local parts to clone this?

thanks!

[getafix]

Yes I'm sure you can... assuming you be able to get the correct value for each component. It probably would take some tinkering, but I'm sure you can get local parts.

[tuff_u_gong]

Yes I'm sure you can... assuming you be able to get the correct value for each component. It probably would take some tinkering, but I'm sure you can get local parts.

thanks! do you know which electronics store carry similar 2-way crossovers? i went to one of DEECO's branches (along Marcos Highway in Marikina) and all i saw were dividing networks. i was thinking i could get a standard two-way crossover to start with so i don't have to build from scratch.

thanks!

[john5479]

Tuff, its better if you have the schematics of the crossover you plan to use, fairly simple and u can use point to point or a simple pcb. you can have the inductors wired as suggested by vircor.

[vircor]

thanks! i guess you're right about reverse engineering. an oscilloscope and winder might be too much of an investment for a DIY newbie.

i plan to build a 2-way speaker with an 8'' bass driver with a dome tweeter.

Sir, am just saying that an oscilloscope is ideal specially in dealing with frequencies, voltage and wave outputs but is heavy on the pocket; an alternative would be a digital multimeter with frequency measurement. A
winder will be important in making your own filter/crossover, speaker, transformers, etc. and i think it's not
much expensive. Since occassional lang naman siguro ang paggawa mo ng projects, you can always let the
guys at Raon wind things up for you according to your specs or order it made by our diy masters.

Regarding your project plan, I think using an 8" driver for the mid-bass is not recommended coz there will be a
gap in the mid frequency range, which for me is very critical. In a 2-way system it is not recommended to
have a woofer larger than 7", anything larger will not faithfully reproduce the midrange frequencies with
realism, clarity and detail since a large driver (8" or greater) is designed primarily to produce bass frequencies
below 200Hz (frequency range is 20-500 Hz) and is too slow to resonate frequencies with authority in the
midrange band of 200Hz-4kHz (can you see the gap already?). I just don't know if it's okay with you the gap
I'm saying but of course you can continue with your project plan.

Just FYI:
Baffle step compensation is an increase in output from a loudspeaker as the size of the baffle becomes
significant in terms of the wavelength of sound for a range of frequencies.  At low frequencies, where the
baffle (the panel the loudspeaker is mounted on) is small compared to the wavelength, the speaker is assumed
to be operating with a spherical radiation pattern. As frequency increases, the size of the baffle becomes
significant, and the spherical radiation pattern no longer applies.  This is also partly to do with the loudspeaker
drivers themselves - as frequency increases, typical cone drivers become more and more directional - this
occurs as the dimensions of the cone become significant with respect to wavelength.

There's a lot of work involved in baffle step compsensation and equalisation, and unless you're very interested
and it's much of a concern, I suggest you leave it for the moment. The person replying to your query is
assuming that you understand a lot on loudspeakers and electronic stuff. Parang nagtanong ka lang kung
paano mag-mix ng dough pero gustong pag-aralan mo na yung buong baking process.

Tama si sir john, mas madali kung may schematics nung crossover. Parang ganito:

6dB/Octave 2-Way Passive Crossover

[tuff_u_gong]

thanks for all your answers vircor and john5479!
with your help i feel that there's a lesser chance i'd get frustrated with this project. 

Sir, am just saying that an oscilloscope is ideal specially in dealing with frequencies, voltage and wave outputs but is heavy on the pocket; an alternative would be a digital multimeter with frequency measurement. A
winder will be important in making your own filter/crossover, speaker, transformers, etc. and i think it's not
much expensive. Since occassional lang naman siguro ang paggawa mo ng projects, you can always let the
guys at Raon wind things up for you according to your specs or order it made by our diy masters.

thanks again for that tip. you're really helping me save time and money here. can you refer anyone from raon who does this well? how about from cubao or somewhere nearer the marikina, QC (cubao) area?

Regarding your project plan, I think using an 8" driver for the mid-bass is not recommended coz there will be a
gap in the mid frequency range, which for me is very critical. In a 2-way system it is not recommended to
have a woofer larger than 7", anything larger will not faithfully reproduce the midrange frequencies with
realism, clarity and detail since a large driver (8" or greater) is designed primarily to produce bass frequencies
below 200Hz (frequency range is 20-500 Hz) and is too slow to resonate frequencies with authority in the
midrange band of 200Hz-4kHz (can you see the gap already?). I just don't know if it's okay with you the gap
I'm saying but of course you can continue with your project plan.

that was also the impression i got based on my own experience with speakers with 8'' and 6'' drivers.. .until i heard a SET tube amp hooked up to this 2-way speaker which had a 22cm bass driver and a very ugly enclosure.    i was dumbfounded by those speakers' mids 

Just FYI:
Baffle step compensation is an increase in output from a loudspeaker as the size of the baffle becomes
significant in terms of the wavelength of sound for a range of frequencies.  At low frequencies, where the
baffle (the panel the loudspeaker is mounted on) is small compared to the wavelength, the speaker is assumed
to be operating with a spherical radiation pattern. As frequency increases, the size of the baffle becomes
significant, and the spherical radiation pattern no longer applies.  This is also partly to do with the loudspeaker
drivers themselves - as frequency increases, typical cone drivers become more and more directional - this
occurs as the dimensions of the cone become significant with respect to wavelength.

There's a lot of work involved in baffle step compsensation and equalisation, and unless you're very interested
and it's much of a concern, I suggest you leave it for the moment. The person replying to your query is
assuming that you understand a lot on loudspeakers and electronic stuff. Parang nagtanong ka lang kung
paano mag-mix ng dough pero gustong pag-aralan mo na yung buong baking process.

you're right, i don't think i'll dare venture into that technical stuff just yet.

Tama si sir john, mas madali kung may schematics nung crossover. Parang ganito:

6dB/Octave 2-Way Passive Crossover

OK. here's a schematic that was recommended to me at diyaudio.com. it's not
exactly the same as the crossover i showed in the pic but it was the schematic
recommended by the guy who talked about the baffle step compensation.

[john5479]

I have a baffle (floorstander) which uses an 8 inch kevlar driver, great mids and bass...although there is some breakup in the highs, this might be due to the driver not really performing well in the upper frequencies. BUT I don't hear any hole in the mid frequency range

[JojoD818]

Ang dami palang DIYer ng speakers dito eh!

Vircor, musta na design mo? Alam mo na pala mag design nyan sir. Kelan ba namin makikita at madidinig yan?

[vircor]

Ala pa nga sir time e, waged worker kasi kaya ayun... medyo dami pa gawa and other priorities.

Siguro in ten years! Ahahahaha!

Last time kasi ako gumawa ten years pa yun! 

[vircor]

Sir tuf,

Sensya na I can't help you regarding a contact in raon, ala kasi ako kilala. Try sir jojo. Kung gusto mo na masimulan project mo pwede naman, you can TEMPORARILY make do with the dividing networks from DEECO if you may.

[jcob]

Sir tuff,

Hope this site helps.
http://www.carstereo.com/help2/Articles.cfm?Car_Audio=Car%20Audio%20Crossover%20Design

this site is all about loud speaker design....

[vircor]

Sir tuf, did you have the drivers for your project already? Kung wala pa here are some suggested brands: Dai-Ichi, Phaser, Konzert, Crown. Of course there maybe better brands but these are the common and affordable ones that are known to be very good performers too, you can opt for the brand of your liking. Better start planning for the baffle coz this is the most time consuming and hardest part in building your project. Use at least 3/4" thick MDF board (kung wala available baka pwede na rin particle board ) and start your layout before cutting it to sizes para walang masayang na cuts. A jigsaw would make cutting easier  and neat, especially so at the drivers' mounting holes. Use industrial strength wood glue para dikit na dikit lalo na yung internal braces. You can use 'tee nuts' instead of mounting the drivers directly to the baffle para secured yung driver, drill a hole and hammer it in (you can add some glue).

Tee Nut

Dry-fit mo muna yung drivers and connectors before applying finishes. Sabi ko nga, you can use those dividing networks from deeco or alexan (teka, tanong ka alexan baka merong crossover kit doon, branches nila sa Divisoria area, SM North EDSA, SM Mega meron ata.) as TEMPORARY kasi madali namang palitan yun kahit finish na project mo, dismount mo lang yung drivers tapos kabit uli.

Teka, bakit nga ba ako napadpad dito I'm not an expert loudspeaker builder, dapat yung mga diy masters ang magbigay ng inputs jan!   

[s2kov]

Anung gamit ng tee nut?

You can use 'tee nuts' instead of mounting the drivers directly to the baffle para secured yung driver, drill a hole and hammer it in (you can add some glue).

Tee Nut

[Gino]

T-nut secures a machine screw to the wood panel. It is basically a nut, as in nut and bolt. The bolt goes through the speaker flange, then through the wood, then through the t-nut. The teeth of the t-nut is driven through the back side of the wood.

[JojoD818]

Ahh those lovely Tee nuts... when I hear those I remember this beautiful chinese lady at T. Mapua St. where I bought my Tee nuts.... 

On a technical note, woofers and subs installation benefit a lot using Tee nuts rather than just using machine/wood screws. The price is less than P5 per set (bolt & Tee nut).

[s2kov]

So, tee nut is basically to protect the wood in case there is a frequent opening of enclosure through the speakers?

[JojoD818]

So, tee nut is basically to protect the wood in case there is a frequent opening of enclosure through the speakers?

Besides that, you use the threads of the tee nut so the wood (and woofer/sub basket) is just "sandwiched" by the tee nut and the bolt. 

[s2kov]

Ganun bah!!!! Bakit kaya nde ganito ginawa nila sa monitor audio?

Besides that, you use the threads of the tee nut so the wood (and woofer/sub basket) is just "sandwiched" by the tee nut and the bolt.