I've already got tons of computers (I'm a computer nerd as well) with 5.1channel audio, as well as cards, but I don't like to waste time. I already wasted a month and still don't have even the woofer finished, and I don't want to order a compression driver only to realize I have to get a mid and then wait even longer to get that and make a box for it, I don't know though, maybe it wont be that bad. Do you really think that I will like just having a compression driver and woofer with no mids? I hate to admit it but half my reason behind having a mid is just for the looks, bigger box, more speakers.
As far as it being a sealed back midrange, well that's the reason why I wanted that midrange
, I don't have to try to make a box that sounds good, just one that looks good.Here's another good question for you, I see lots of 12V powered active crossovers made for car audio, some with not bad crossover points, do you think I should consider getting one of those since they run about $20 or so, or is there something bad about them that I don't know of.
Thank you for all of your help, I do appreciate it.
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I'd use a computer with 5.1 to optimise crossover points, and then do a bit of soldering to make your own active crossover based on what you did with the Foobar2000 setup. It'd be a case of a few resistors and capacitors around a couple of op-amps. If you want an external active crossover, the Behringer stereo 2-way or mono 3-way works nicely, and are very cheap 2nd hand.
As I said earlier, a lot of PA speakers have a 15" woofer and a compression driver (some use piezos, but lets not go there). I think it'll do what you're after.
Chris
As I said earlier, a lot of PA speakers have a 15" woofer and a compression driver (some use piezos, but lets not go there). I think it'll do what you're after.
Chris
Well I'm still on the fence as to whether to buy the mid now, or later.
In the meantime, yesterday one of two Pro amps I ordered came in. It's a Crest Audio LA 601 (150WPC @ 8ohm or 550W Bridged @8ohm) which I bought fairly cheap and as parts and repair as they said only one channel worked. After having a look inside, and bringing it up slowly on a variac with a 60 watt ballast, I tried it straight to the mains, what do you know, both channels work perfectly
.You know, I've so far bought 4 recievers/amplifiers IN A ROW off of ebay, all said to be broken, and I get each one for a good price, and each come to my home, and work perfectly, I don't know what it is but I just can't seem to buy a broken reciever/amplifier. I got 2x Teac AG-750 recievers, they worked fine, a Pioneer SX-424, that worked fine, and that crest audio amp, and they all work fine despite their listing saying they are not working, some said completely dead, some said one channel dead, but either way everything works for me.
Now later this week, my other pro amp, Behringer A500, which Is said to have 1 broken channel, will arrive. Let's see if that will be the fifth in a row to work fine after being sold cheaply and for parts and repair.
Oh one more comment about the parts express order, I'm hesitant to not order a mid because I really think I want to get one, and will have to order it later, which will cost more to ship it later than to ship it now along with the compression drivers and what not.
I'm going to check out the foobar2000crossover in the meantime.
Hello,
Sorry but I checked and the prices of just 1 of those tweeters alone is more than I've spent on the amp to power it. Unfortunately its about the same for that 8" you suggested.
So I can't purchase either of those but thank you for your contribution.
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Hi, this is my first post here (although I’ve been reading this forum for a long time), so please go gentle.
TheTubeAmper:
15” drivers start to ‘beam’ at 916hz, beaming is an effect where the sound becomes more and more directional as the frequency increases, and this happens when the wavelength of the sound gets shorter than the width of the driver (619hz has a wavelength of about 15”).
Just a thought:
In the past I’ve had great success building a simple 2.1 system using a single 15” driver and two or more Fatal Pro 3FE25s, these little 3” drivers sound nice and have a frequency response from 150hz to 20khz, they cost about $19 each.
I’ve also used these drivers in an array of 4 drivers also with very good results, and I know of a couple of commercial designs that also use 4 a side.
Alan
TheTubeAmper:
15” drivers start to ‘beam’ at 916hz, beaming is an effect where the sound becomes more and more directional as the frequency increases, and this happens when the wavelength of the sound gets shorter than the width of the driver (619hz has a wavelength of about 15”).
Just a thought:
In the past I’ve had great success building a simple 2.1 system using a single 15” driver and two or more Fatal Pro 3FE25s, these little 3” drivers sound nice and have a frequency response from 150hz to 20khz, they cost about $19 each.
I’ve also used these drivers in an array of 4 drivers also with very good results, and I know of a couple of commercial designs that also use 4 a side.
Alan
Hello,
Firstly, it's nice to see someone else join DiyAudio, I hope you enjoy your time here
Second, I think I did experience that beam effect you described when using this as full range. However can you please clarify if you meant 916hz or 619hz (you said both so I don't know which) because that also goes with my third point.
Third, I would've considered getting some of those drivers you suggested, I forgot to post it but on saturday I ordered the following:
An externally hosted image should be here but it was not working when we last tested it.
Pyle PDMR6 6-1/2" Sealed Back MidrangeAn externally hosted image should be here but it was not working when we last tested it.
2x Recessed Speaker Wire Terminal Cup Banana 5-Way Binding PostsAn externally hosted image should be here but it was not working when we last tested it.
Pyle PDS182 1.5" Titanium Horn Driver 8 OhmAn externally hosted image should be here but it was not working when we last tested it.
Goldwood GT-400PB 1" Horn 1-3/8"-18 TPIAn externally hosted image should be here but it was not working when we last tested it.
Speaker Crossover 2-Way 8 Ohm 5,000 Hz 150W (for the mids and highs box)
An externally hosted image should be here but it was not working when we last tested it.
800 Hz Low Pass 8 Ohm Crossover (for the 15" woofer)So hopefully you meant to say 916Hz because that would mean that my 800hz low pass will stop the beam effect.
Thanks.
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isn't the sub you built the cubo 15? (this design has limited bandpass)
if your building the mid and horn into a seperate enclosure do you need a sealed back midrange?
i'm also curious about your crossover choices because there seems like there a broad overlap in frequency bands or is there an active element that i missed?
if your building the mid and horn into a seperate enclosure do you need a sealed back midrange?
i'm also curious about your crossover choices because there seems like there a broad overlap in frequency bands or is there an active element that i missed?
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Hello,
That is correct, I've built the Cubo 15 (extended version).
That is correct, the horn and mid will be in their own box (and really can be used standalone without the woofer). The reason I went with a sealed midrange is so I don't have to worry about making a specific box to make it sound good. It'll just sound good as it is, it saves me work.
As far as the overlap you talk about, I think you mean that the midrange will also be doing the same frequencies (under 800hz) as the woofer. If that is what you mean, than yes, you are correct. I don't think it will be too much of an issue at the moment, and I plan to modify the mid and high crossover to convert the mid's low pass to a bandpass (from 800hz to 5khz).
I'll be getting the parts from parts express today, and yesterday I finished the Cubo 15 so I can try it out today
Hello,
Just got back from testing everything hooked up. Tested everything for 1 hour.
I am more than happy with the results, this system sounds just as good, if not better, than any DJ I've ever heard. Everything is crisp, clear, and defined, and nothing is overpowering anything else, it's all well balanced and definitely loud enough. I'm amazed at how nice the cubo15 sounds now that it is completely finished. Its amazing how no matter where I am in relation to it, the bass is good and constant.
However there was one casualty....Literally one minute before I was going to shut everything off I was startled with a loud and violent POP!!! As I went to shut everything off I could hear a sort of bubbling and sizzling sound comming from my woofer's amp, the Crest Audio LA 601 I recently purchased. I knew exactly what the problem was, I remember when I had the amp open, the filter caps had the slightest, nearly unnoticeable arch to the top of them. Another hint that the caps were bad was how I always noticed when playing at a decently loud volume with a good amount of bass, the power lights on the amp would dim far more than they should.
I've not yet opened the amplifier to confirm my thoughts, I am sure this is what the issue is. I see the purchase of 2x expensive 10,000uf (I think they are like 70V) caps in my near future.......
Glad to hear everything turned out well for you. Putting the mid on a bandpass might not be necessary if you are satisfied with the power handling. A closed back mid should not have enough low frequency response to cause comb filtering problems with your 15" woofer, and adding complexity when you don't need it is never a good idea. Using a bandpass filter will simply serve to keep low frequencies from being converted into heat in the voice coil of your mid driver--Something which you may, or may not need.
I can give you a diagram of how it was all wired. Gimme a sec.
Attachments
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I'm not really sure how the crossovers could've hurt the amp.
And really I think the cap was bad the whole time, considering the behavior of its power lights, but the diagram (hopefully it tells you something) is in my above post.
Oh and if you want you can take a look at my thread I made just for the amp repair: http://www.diyaudio.com/forums/solid-state/250442-crest-audio-la601-repair-help.html#post3803526
Nothing prevents frequencies less than 200hz but I can't say I care. Unless it will cause some huge stability issue, I think I'll just continue to not care considering it sounded great until the amp blew.
I don't know what exactly you mean with this reactive mess stuff. I buy a pre-built crossover from a good supplier that is made to be on an 8 ohm woofer, and I connect it to an 8 ohm woofer and I expect it to just plug and play. Are you saying it is not so?
You can look at the parts-express page for it if you want: 800 Hz Low Pass 8 Ohm Crossover | 266-450
One thing I should mention, it is possible that I was going over the 250watt RMS on that crossover. I have no way of knowing considering the Crest Audio LA 601 does 550W RMS in bridge mode, however I strongly think I didn't go over 200watts (thought I really couldn't tell you).
Thanks for your help.
Why is an iron inductor a bad thing?
Correct me if I'm wrong but your concerned that sub 200hz frequencies will damage the mid? If that is your concern than if you could, suggest me a rock bottom cheap solution to it. If it only costs me $2 to add a cap or coil to the existing crossover to filter out 200hz, then I'm open to suggestions.
You know, for years I didn't have a single sound system that could compete with a simple pair of less than decent sony headphones. Nothing I had matched the clarity of headphones in general. This system does. No matter how cheap, it is clean and clear sound, nothing is distorted, nothing is drown out, nothing is muffled, everything is bright and clear.
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Switch off the woofer, play the midrange full-range, and hear exactly what its doing. The driver isn't meant to see LF signal, so it has very little linear travel (so you'll get distortion from the mid when the bass hits). You'll also wipe out its thermal ratings by applying a lot of out-of-band power.
A series cap on the input of the amplifier (cheap) or in series with the mid driver (expensive) will help, but I'd recommend 2nd order as a minimum.
Chris
PS - I strongly recommend you get a pair of Behringer B2031 monitors. Active or passive, whichever. They're very very good for the money, and will give you a solid reference for future builds.
A series cap on the input of the amplifier (cheap) or in series with the mid driver (expensive) will help, but I'd recommend 2nd order as a minimum.
Chris
PS - I strongly recommend you get a pair of Behringer B2031 monitors. Active or passive, whichever. They're very very good for the money, and will give you a solid reference for future builds.
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