What books do you recommend for me?
The problem with most local speakers is that they lie about the speaker power and sensitivity, even the T/S parameters don't escape this. There are few brands that do serious work on this and when they do, the prices are scary.
I'm going to learn how to design a crossover, can you give me some guidance on where to start?
I wanted to do it myself just to learn... I won't care too much about the sound, what I want here is learning. But good sound is everyone's goal
I intended to buy all the speakers with the same impedance (4 ohms) and then use the crossover in an amplifier with an impedance of 4 ohms. How can I do this? I would have to make a crossover board
I'm not sure where to start, really. It depends on what background understanding you have on how resistors, capacitors and inductors respond to frequency in various circuits. And then it goes from the basics of the filters themselves, to adjusting response slopes, to notch filters and Zobel networks to smooth frequency responses and impedances...
Rod Elliott has a couple of introductory articles, which you might find of some use...
https://sound-au.com/lr-passive.htm
https://sound-au.com/articles/crossover-tables.htm
(Those are actually fairly basic, but I think they'd still look daunting to a complete beginner).
To be honest, and I mean this well, asking a question like that suggests you don't yet understand the background needed for what you want to do (and apologies if you do - it might just be a communication thing.) It's not just a case of sticking together some drivers of the same impedance and then using it with an amp that can handle that impedance.
For one thing, the quoted impedance of a driver is only nominal. In reality, the impedance varies with frequency - Did you know that impedance is frequency-specific? That's part of the electronics basics that you'd need to know.
A nominal 4 ohm driver might vary from less than 2 ohms to more than 16 ohms (perhaps much more) at different frequencies. And two different nominal 4 ohm drivers might have very different impedance curves.
And then, the impedance presented to the amp won't be the same as the impedance of the individual drivers... the impedance will be affected by the crossover components themselves, and how the whole set of components works together. Matching three different drivers, all with wildly differing impedance curves, into a whole that presents a good enough impedance curve to the amp, is not trivial.
Learning how to design speakers is difficult and takes a lot of time and effort. And that's why I'd strongly recommend building from a published DIY design first. I don't think you're near ready to design your own from scratch yet.
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I just noticed this thread. It's talking about an ultra-simple 2-way, but it shows how to attenuate a driver signal to match loudness.
I think there's no "ideal" per se, but a LFC=300-500Hz and HFC=4500-6000Hz would be a good start, IMHO. But it depends on your speakers...
Personally :
1 - I try to avoid transition FCs that are in a region of the curves of the speakers to match are tormented, particularly for the Woofer and Midrange transition. If doable, at least +/- 1 Oct. of reasonable linearity accross FC is preferable - more is of course better, if possible...
2 - I prefer a low transition FC between the Woofer and the Midrange speakers : 300 - 500Hz rather than 1000Hz. This avoids to cut the voices "in two speakers" : they are plentifully located in the Midrange speaker - notably for the man voices - like if it was a Wide Band loudspeaker. But this implies that your Midrange has a significant size and ability to reach low-midrange / high-bass register...
On my DIY 375L 3-ways speakers below, the Midrange speaker is a 8" one. LFC=400Hz / HFC=5000Hz, while the FS of the midrange is 80Hz, loaded in a sealed enclosure of 7.5L, offering a natural cutoff at 110Hz, that is to say 2 octaves under LFC.
T
Some suggested books include The Speaker Design Cookbook and Speaker Building 101.
Free resources include this website (e.g. "Designing Crossovers Without Measurement" thread) and articles by Paul Carmody (Undefinition) and Curt Campbell (Speaker Design Works) : Paul has a very good Q and A section for people new to speaker building.
It looks like you haven't bought the drivers, is that right?
If not, I'd strongly suggest (again) that you build an existing project by a noted designer which has been widely built and reviewed, you will be happy and reduce swear word output. You will still learn a lot.
But If you really, really, really don't want to do that, and before spending any money, and only after you do heaps of reading and research:
The reason people keep telling you to start with an established design is that they want you to save you money, be happy with what you build and enjoy the hobby.
Geoff
Free resources include this website (e.g. "Designing Crossovers Without Measurement" thread) and articles by Paul Carmody (Undefinition) and Curt Campbell (Speaker Design Works) : Paul has a very good Q and A section for people new to speaker building.
It looks like you haven't bought the drivers, is that right?
If not, I'd strongly suggest (again) that you build an existing project by a noted designer which has been widely built and reviewed, you will be happy and reduce swear word output. You will still learn a lot.
But If you really, really, really don't want to do that, and before spending any money, and only after you do heaps of reading and research:
- start with a two way, not a three way, much easier and fewer crossover parts;
- use drivers which are widely used, available in your country and easy to work with;
- look for projects which use those drivers and see how they're implemented in those designs.
The reason people keep telling you to start with an established design is that they want you to save you money, be happy with what you build and enjoy the hobby.
Geoff
Lots of English language websites out there
Lynn Olsen
http://www.nutshellhifi.com/library/speaker-design2.html
Paul Carmody
https://sites.google.com/site/undefinition/diy-speaker-faqs
Personally I prefer 8R and 16R drivers as my old school amps are less dirty driving loads of higher resistance and less prone to over heating.
Power is cheap, magnets are not so that's why less efficient drivers are cheaper sometimes but all can work to provide good sound
The drivers mentioned here are no longer available new but it is a good discussion on the whys and wherefores of crossovers and design and why paying more for better drivers can save time and money
https://www.diyaudio.com/community/threads/diyaudio-reference-speaker-project.25590/
I don't think that PRV lie about their drivers
https://prvaudio.com/products/6mb400-6-5-inch-pro-midbass-loudspeaker/
Highly efficient midrange drivers can be a trap, if you use one you then need really big woofers to keep up and big woofers are not cheap.
Or you have to pad them well down with resistors and waste power as heat, I have some Fostex 5" midrange here I don't use as they need a pair or 12" woofers to be even close in volume and even using a big 15" woofer they seem bass shy
Also; and this is very important; you haven't told us anything about where you will be using these speakers after they are built and what amplifiers and playback system you are going to use. No point in making something too big for the room as a beginners project
Lynn Olsen
http://www.nutshellhifi.com/library/speaker-design2.html
Paul Carmody
https://sites.google.com/site/undefinition/diy-speaker-faqs
Personally I prefer 8R and 16R drivers as my old school amps are less dirty driving loads of higher resistance and less prone to over heating.
Power is cheap, magnets are not so that's why less efficient drivers are cheaper sometimes but all can work to provide good sound
The drivers mentioned here are no longer available new but it is a good discussion on the whys and wherefores of crossovers and design and why paying more for better drivers can save time and money
https://www.diyaudio.com/community/threads/diyaudio-reference-speaker-project.25590/
I don't think that PRV lie about their drivers
https://prvaudio.com/products/6mb400-6-5-inch-pro-midbass-loudspeaker/
Highly efficient midrange drivers can be a trap, if you use one you then need really big woofers to keep up and big woofers are not cheap.
Or you have to pad them well down with resistors and waste power as heat, I have some Fostex 5" midrange here I don't use as they need a pair or 12" woofers to be even close in volume and even using a big 15" woofer they seem bass shy
Also; and this is very important; you haven't told us anything about where you will be using these speakers after they are built and what amplifiers and playback system you are going to use. No point in making something too big for the room as a beginners project
Do you know this? Maybe simpler to read. Should cover most of your questions, even some colorfull pictures and sources in Brasil.
http://dirsom.com.br/index_htm_files/Curso Caixas Acusticas - Faca voce mesmo.pdf
http://dirsom.com.br/index_htm_files/Curso Caixas Acusticas - Faca voce mesmo.pdf
After reading this I looked on Ebay for Car Audio XO's out of curiosity.
I was surprised to find this XO using very decent quality parts at a bargain price.
( I don't know if Ebay is available in all countries )
I have ordered two just for the parts > BARGAIN 🙂
https://www.ebay.com.au/itm/1659710...XnNyHnV7/Gc89tZTuKzFZiIJEQ==|tkp:BFBM3PHOtutj
Out of interest, how do you know that the Chinese branded components are good?
The BARGAIN I see is no Electrolytic capacitors > just Polly caps.
Plus the 3 inductors ( air & core ) would cost something like $60 in Australia.
The 'cherry on top' is two 10W resistors, one Pollyswitch AND a useful PCB.
Plus the 3 inductors ( air & core ) would cost something like $60 in Australia.
The 'cherry on top' is two 10W resistors, one Pollyswitch AND a useful PCB.
I just found the following thread, which I had bookmarked but had forgotten about...
https://www.diyaudio.com/community/...igning-crossovers-without-measurement.189847/
(Don't think it's been linked here - but if it has, it's so good it's worth linking twice 🙂 )
https://www.diyaudio.com/community/...igning-crossovers-without-measurement.189847/
(Don't think it's been linked here - but if it has, it's so good it's worth linking twice 🙂 )