Greetings. I have recently been tinkering with speaker building and decided to post a question here based on advise from another forum.
I plan to build a tiny desktop speaker for using a Tymphany SDS Series 830855 4" Woofer 8 Ohm and a Dayton Audio AMTPOD-4 tweeter.
I plan to use two Tymphany 830878 3-1/2" Passive Radiator per speaker box.
The use of the tweeter is because I got me a pair on craigslist to add to my car. I saw this project on Pinterest and I thought "wow, I think I can make this".
I have never built a speaker before, but I am good with small wood working projects. I also understand the very basics of how a loadspeaker works.
Can someone please help me with a crossover design ? Or point me to an off the shelf crossover I should use ?
What would be the smallest cabinet I can use ? Do I need two passive speakers per box ? I would like to build something smaller than the Pioneer BS22 speakers but with a nicer bass. I am not sure if I asked the question right. Please bare with me.
I plan to build a tiny desktop speaker for using a Tymphany SDS Series 830855 4" Woofer 8 Ohm and a Dayton Audio AMTPOD-4 tweeter.
I plan to use two Tymphany 830878 3-1/2" Passive Radiator per speaker box.
The use of the tweeter is because I got me a pair on craigslist to add to my car. I saw this project on Pinterest and I thought "wow, I think I can make this".
I have never built a speaker before, but I am good with small wood working projects. I also understand the very basics of how a loadspeaker works.
Can someone please help me with a crossover design ? Or point me to an off the shelf crossover I should use ?
What would be the smallest cabinet I can use ? Do I need two passive speakers per box ? I would like to build something smaller than the Pioneer BS22 speakers but with a nicer bass. I am not sure if I asked the question right. Please bare with me.
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Sir, that is a fair question. I think I would like to reinvent the wheel because I do have the woofers. Also, isn't every speaker idea in this and many other forum reinventing the wheel ? Isnt that the spirit of invention itself ? My question on two speakers was, can I use two passive speakers for one woofer ? I ask this because my understanding is a passive speaker should be same size or larger than the active speaker. Is this correct ?
The tiny speaker I'm building uses only the 3.5 inch Peerless/Tympany TG9FD1008, and the Peerless 3.5 inch passive radiator, thereby avoiding the need for a crosssover. If you're new at this, getting a crossover right can be difficult. I wrote out a recommended procedure for this on my hobby website: ephaseaudio.com
Click on Audio, then scroll down to "My thoughts on speaker design".
Click on Audio, then scroll down to "My thoughts on speaker design".
I use to have a cat that looked just like yours ! You have a treasure trove of various things in your site, I have no other way to summarize my initial thoughts. I have much to read and learn from you. I am a little stuck on my choice on the woofer and tweeter. I got them thinking I will put them in my car, actually that is what got me into this idea of building things. Then I realized while the diameter of the woofer fits, the depth is too deep for my doors. So I decided I will build something with them for home use. I have an older onkyo receiver I found at a sale I want to use this with. It came with a Pioneer Speaker and my goal here is to outdo that speaker. I put the speaker inside a small box (.5 cubic feet square) and even with equalizer all the way up, it doesnt have much out put on the high end. Some of the higher pitched voices sound like Norah Jones for the lack of better expressiojn.
SHORT TERM SUGGESTION:
Use your current 0.5cuft SDS 830855 Speakers by adding a mounting board for your AMTPOD and adding a 5,000Hz crossover. Do not invest in passive radiators. Attached crossover based upon Dayton FRD ZMA data. CROSSOVER parts are EXPENSIVE, and I do not have any measurement data, so you will get less than optimum results from just datasheet FRD ZMA values.
The Dayton Audio AMTPOD-4 are super tweeters which require a crossover above 4,500Hz. The SDS 830855 shows breakup above 5kHz.
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The successful Pioneer BS22 speakers are a traditional 2-way design in a 7.1W*12.8H*8.5D (0.3cuft)cabinet. The waveguide on the tweeter provides controlled directivity and allows a smooth M->T polar transfer at a lower crossover frequency. Solid engineering. Build a similar 2-way KIT and you will be HAPPY with the sound.
LONG TERM SUGGESTION:
Dayton Audio BR-1CAB BR-1 6-1/2" 2-Way 0.3cuft Speaker Cabinet Pair $63
SB17MFC35-8 midbass (159mm diameter) $58
SB26STC-4 dome tweeter (100mm diameter) $33
2kHz BW3/BW3 crossover(available)
Attachments
Hello! Maybe take a look at my Dayton Mini Monitor speakers. They are small footprint and would fit your application very well:
http://www.diyaudio.com/forums/multi-way/308576-dayton-mini-monitor-illustrated-guide.html
http://www.diyaudio.com/forums/multi-way/308576-dayton-mini-monitor-illustrated-guide.html
@JenniC, example of the AMTPODs...
Bantams @ Parts Express.
The Bantams | Parts Express Project Gallery
J.
Bantams @ Parts Express.
The Bantams | Parts Express Project Gallery
J.
This is probably the reply I was hoping for. Someone pointed out I was pointing to Dayton units instead of Tymphany for the Woofer. Is your suggestion valid for the tymphany ?
If you look at the FR plots of the AMTPODs and that Peerless woofer....
- The AMT doesn't seem to like <5KHz.
- The woofer has large peaks/breakup a little past 5KHz.
Looking at the Bantam driver ND91-4, that holds on until 9-10KHz and has seems to have a more benign breakup.
I'd also suggest that one 3.5" PR is not enough for a 4" woofer.
WinISD suggests that an ND91-4 in 2.5L ported enclosure can achieve 60Hz.
Would that be small enough/suitable?
- The AMT doesn't seem to like <5KHz.
- The woofer has large peaks/breakup a little past 5KHz.
Looking at the Bantam driver ND91-4, that holds on until 9-10KHz and has seems to have a more benign breakup.
I'd also suggest that one 3.5" PR is not enough for a 4" woofer.
WinISD suggests that an ND91-4 in 2.5L ported enclosure can achieve 60Hz.
Would that be small enough/suitable?
It's been said that the optimal passive radiator is twice the size of the active woofer, which may be true, but not a big deal. I built a system with an 8 inch active woof and an 8 inch PR, and a tweeter, and it sounded amazing.
Hard cone woofers (aluminum, Kevar, etc.) always have a big FR peak right where the ear is most sensitive (3-6kHZ), which must be attenuated way down or the speaker will be hard to listen to for long periods. That means either a relatively low crossover point (below 1kHZ) or a high order crossover (24dB/oct.). Because of this, hard cone woofers are only best for 3 way or higher systems.
I put an 8 inch kevlar woofer with a TG9FD1008 peerless/Tympani 3.5 inch full range driver (in a good sub-enclosure), crossed at 480HZ with a 4 pole active crossover (ahead of poweramps), and it sounds VERY good. Keeping crossover points out of the 1kHZ - 6kHZ freq. region improves imaging (stereo effects), and avoids the abrupt change in off axis response that often happens when going from a large diameter driver to a small 1 inch dome or whatever. Plus, once you've got an active crossover chassis built up, it's not a lot more trouble to add active EQ to pump up the low bass, so my speakers are acoustically pretty flat down to below 30HZ. That's a huge feature. And it's clean tight bass because the box is sealed, so mechanical damping is good at all frequencies. The TG9 rolls off above about 15kHZ, but I don't miss the treble above 15kHZ at all. It's a rare done tweeter that works well below about 3kHZ with a 1 pole passive crossover. Always check out the FR curves on any drivers you consider using, even though it's arguable that published graphs aren't always real accurate. Gradual changes over frequency can be corrected, but abrupt ones are pretty hard to deal with.
Hard cone woofers (aluminum, Kevar, etc.) always have a big FR peak right where the ear is most sensitive (3-6kHZ), which must be attenuated way down or the speaker will be hard to listen to for long periods. That means either a relatively low crossover point (below 1kHZ) or a high order crossover (24dB/oct.). Because of this, hard cone woofers are only best for 3 way or higher systems.
I put an 8 inch kevlar woofer with a TG9FD1008 peerless/Tympani 3.5 inch full range driver (in a good sub-enclosure), crossed at 480HZ with a 4 pole active crossover (ahead of poweramps), and it sounds VERY good. Keeping crossover points out of the 1kHZ - 6kHZ freq. region improves imaging (stereo effects), and avoids the abrupt change in off axis response that often happens when going from a large diameter driver to a small 1 inch dome or whatever. Plus, once you've got an active crossover chassis built up, it's not a lot more trouble to add active EQ to pump up the low bass, so my speakers are acoustically pretty flat down to below 30HZ. That's a huge feature. And it's clean tight bass because the box is sealed, so mechanical damping is good at all frequencies. The TG9 rolls off above about 15kHZ, but I don't miss the treble above 15kHZ at all. It's a rare done tweeter that works well below about 3kHZ with a 1 pole passive crossover. Always check out the FR curves on any drivers you consider using, even though it's arguable that published graphs aren't always real accurate. Gradual changes over frequency can be corrected, but abrupt ones are pretty hard to deal with.
It looks like my drivers will not work for the task at hand. Thank you for pointing this out.
Do you have a write up on that build somewhere ? I would love to see. I also didnt know that the hard cones had a known peak. Would you call it midrange brightness ? Would that make hard cones suitable for center channel speakers ? Is a general purpose active crossover usually better than a custom designed passive crossover ? On a side note, if the woofer and tweeter has different sensitivity, with the woofer being much less sensitive than the tweeter, is this something one would correct in a crossover ?
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