Hi guys.. I am now starting to investigate active crossovers. There seems to be a lot of discussion here regarding them being better than passive filters or xo's.. Questions:
1.) Are they better?
2.) What is a good budget 2 or 3 way active crossover?
3.) The ones I have seen all seem to have XLR inputs.. is this the only way they come, and can you not use rca's or other types of connectors??
4.) If it is better than passive.. then why??
Thanks guys
1.) Are they better?
2.) What is a good budget 2 or 3 way active crossover?
3.) The ones I have seen all seem to have XLR inputs.. is this the only way they come, and can you not use rca's or other types of connectors??
4.) If it is better than passive.. then why??
Thanks guys
Well number 3 is because most are meant for Professional systems, or "Hi End" systems that use balanced inputs/ouputs (XLR). If you find a PA one with 1/4" phono plugs, they make 1/4" to RCA adapters.
Active XO's are pretty easy to DIY, its just an opamp some caps and resistors. Then you cascade them for steeper slopes (12db, 24db, 48db). 48dB/octave isn't really practical in passives, but quite able in active.
But the real goal is that a poweramp can power each driver. Also the crossover points are much more accurate, as the impedence of the speaker doesn't matter at all (which is unstable to say the least). The crossover point is established by the cap and the resistor in the opamp circuit, so since you can use smaller film capacitors (like 0.33uF and less), you can get ones with 2% tolerance fairly easily, and then 1% or better resistors, and your crossover is now very stable.
Also since each driver has its own amp ideally you can use invidual attentuation to match the drivers level much better. Instaed of using L-pads or resistors that can mess up the Q of a driver, you just adjust the signal going to the amp.
Remember to use a Capacitor on the tweeter though, to keep low frequencies (such as turn on DC thumps) away. Since a tweeter has little excursion, they don't like that stuff.
Active XO's are pretty easy to DIY, its just an opamp some caps and resistors. Then you cascade them for steeper slopes (12db, 24db, 48db). 48dB/octave isn't really practical in passives, but quite able in active.
But the real goal is that a poweramp can power each driver. Also the crossover points are much more accurate, as the impedence of the speaker doesn't matter at all (which is unstable to say the least). The crossover point is established by the cap and the resistor in the opamp circuit, so since you can use smaller film capacitors (like 0.33uF and less), you can get ones with 2% tolerance fairly easily, and then 1% or better resistors, and your crossover is now very stable.
Also since each driver has its own amp ideally you can use invidual attentuation to match the drivers level much better. Instaed of using L-pads or resistors that can mess up the Q of a driver, you just adjust the signal going to the amp.
Remember to use a Capacitor on the tweeter though, to keep low frequencies (such as turn on DC thumps) away. Since a tweeter has little excursion, they don't like that stuff.
JeffG said:
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Your questions are sort of subjective; are they better? For some things, yes. Budget? Depends. Only XLR inputs? On pro audio modeals, probably. For DIY, no- you could use something else. I don't mean to be dismissive- but your questions have a lot of right answers.
I think that some googling and archive searching would help you a lot. There's a lot of information out there.
The key benefits of active crossovers- they allow you to use more of your amplifier's power, since the passive components don't eat up the output. Active crossovers allow for things such as digital delay for a driver to improve time alignment.
I know that you're considering the FE207E- and if you're asking about active crossovers, I've got to say that we might be interested in the same sort of design.
Right now I am running a compromised set of tower speakers (somewhere between ML TL and bass reflex) using Eminence Beta 8s. The bass response isn't there, and I have a crossover at 4 khz. I thought I knew what I was doing, but I didn't quite. It was a great learning experience for me, and I feel fairly confident that my next stab at DIY speakers will be much more satisfying. I designed my current speakers with Martin's mathcad worksheets; I just didn't understand that the bass deficiency I planned on fixing with EQ would be so severe.
I don't have any money right now, but I think that my next set of speakers will be something like a fostex full range driver and an Adire subwoofer; most likely sealed. I'll most likely bi-amp, with my Hafler DH-500 driving the subs, and a gainclone or two for the top end. I haven't done any real research into the active crossovers, though--- it just doesn't seem important right now, since I can't even afford to build anything yet.
Please take a look at the links above, and also the Orion (linkwitz) and the Basszilla- http://store.hifiauthority.com/olsherkits.html.
I will have to be sold on the idea of a dipole speaker before I go for either of those; but I have a spare driver sitting around so it would be cheap to give it a try.
The most underrated advantage, or maybe misunderstood, is the dampening (IMO) increase. The control the amp has over the driver cone is phenomenally better if there is no passive components to decouple it. Distortion goes down and dynamics go up to such a degree that it's impossible not to notice. BTW I mean true active bi-Amping.
This is a good link that explains all the advantages and disadvantages of Active vs Passive filters.
http://sound.westhost.com/bi-amp.htm
This is a good link that explains all the advantages and disadvantages of Active vs Passive filters.
http://sound.westhost.com/bi-amp.htm
I would like to add two things.
1.) XLR connectors do not matter for interconnect lengths of less than 25 feet. The equipment which features XLR connectors, does it for pro-use. You can make an XLR to RCA conversion by shorting the two pins of XLR connector, the XLR-1 with the XLR-3. This will constitute the "ground," or the "shield" of RCA. The XLR-2 is the "hot" or the "positive" pin, and continues into the RCA as such.
2.) High-end, 2-way, stereo, active crossovers with unbalanced (R.C.A.) inputs and outputs are available in the form of D.I.Y. kits. Check out Michael Chua's www.ampslab.com
4.) The best commercial model for its price is Behringer's Super-X Pro CX2310, which is a 2-way, stereo, active crossover, albeit with XLR connectors.
1.) XLR connectors do not matter for interconnect lengths of less than 25 feet. The equipment which features XLR connectors, does it for pro-use. You can make an XLR to RCA conversion by shorting the two pins of XLR connector, the XLR-1 with the XLR-3. This will constitute the "ground," or the "shield" of RCA. The XLR-2 is the "hot" or the "positive" pin, and continues into the RCA as such.
2.) High-end, 2-way, stereo, active crossovers with unbalanced (R.C.A.) inputs and outputs are available in the form of D.I.Y. kits. Check out Michael Chua's www.ampslab.com
4.) The best commercial model for its price is Behringer's Super-X Pro CX2310, which is a 2-way, stereo, active crossover, albeit with XLR connectors.
JeffG said:
I don't know your budget, but Marchand has several models over a large price range.
Quality is very good imo
http://www.marchandelec.com/
Re: Re: Active crossover questions?
Agreed!
I have 2 crossovers from Marchand, a XM-9-3KK 3 channel crossover and a XM44-4 4-way crossover. The XM44 has slots for plug in modules for Shelving filters, notch filters, time delay, and such, also is capable of 1st, 2nd, 3rd, 4th and 48db slopes as well as asymmetric slopes. Very good unit for DIY and experimenting, and it sounds very smooth and quite.
Duck-Twacy said:
Agreed!
I have 2 crossovers from Marchand, a XM-9-3KK 3 channel crossover and a XM44-4 4-way crossover. The XM44 has slots for plug in modules for Shelving filters, notch filters, time delay, and such, also is capable of 1st, 2nd, 3rd, 4th and 48db slopes as well as asymmetric slopes. Very good unit for DIY and experimenting, and it sounds very smooth and quite.
1.) Are they better?
I think so, because you can do pretty much any type of signal manipulation with an active cross over. And I think the system becomes less complex with active filters.
2.) What is a good budget 2 or 3 way active crossover?
If you make a bread board solution you only have to pay for something like 6 opamps per channel, some resistors and caps + a power supply and casing. The last part will probably be the most expensive.
3.) The ones I have seen all seem to have XLR inputs.. is this the only way they come, and can you not use rca's or other types of connectors??
You can use what ever you like, XLR is often used for professional and other equipment that uses balanced signals.
4.) If it is better than passive.. then why??
If you think of a passive XO you can only remove energy, this means that you have to take care when you select your drivers to match them so they have pretty the same sensitivity. With an active XO this is not a problem, because you use the XO to level adjust the different channels.
I can only recommend that you try to go active
\Jens
I think so, because you can do pretty much any type of signal manipulation with an active cross over. And I think the system becomes less complex with active filters.
2.) What is a good budget 2 or 3 way active crossover?
If you make a bread board solution you only have to pay for something like 6 opamps per channel, some resistors and caps + a power supply and casing. The last part will probably be the most expensive.
3.) The ones I have seen all seem to have XLR inputs.. is this the only way they come, and can you not use rca's or other types of connectors??
You can use what ever you like, XLR is often used for professional and other equipment that uses balanced signals.
4.) If it is better than passive.. then why??
If you think of a passive XO you can only remove energy, this means that you have to take care when you select your drivers to match them so they have pretty the same sensitivity. With an active XO this is not a problem, because you use the XO to level adjust the different channels.
I can only recommend that you try to go active
\Jens
Hi Jeff
I can't tell you whether active is better than passive - I suppose there might be reasons for using both. I like active XO's for a couple of reasons:
1) I like high sensitivity drivers/speakers and I'd rather not see anything between them and the amps. I agree with kingdaddy regarding distortion and dynamics - I'm not much of an audiophile, but what I hear in my own system between active and passive is quite a large difference. Whether you'll like the difference of course, is up to you.
2) Flexibilty - I like building speakers but I don't particulalrly like messing with electronics. 😀 The flexibility that an active XO gives me is worth it just for the lack of hassles vs getting a passive XO right. I just bought a 7 channel amp from Outlaw (sounds pretty nice with music) and along with an active 3-way XO, I can push 6 drivers from a very compact package and just dial the XO points in. I have some gain control for each frequency band (input and output) as well as response control for the XO piont itself. The simplicity of it when you're building a multiway system(s) is hard to beat.
Budget XO's -
I've only used Marchand XM1's up to this point but I'll have an Ashly 3-way in here this week. I suppose these are both budget units ($400.00 on sale for the Ashly and $30.00 each for the XM1 kits) compared to the more expensive Marchands at twice the price of the Ashly. Behringer makes a 3-way for ~129 bucks (CX3400) and the DBX234 is around $200.00. Behringer also makes a digital 3-way if you don't mind the A-D and D-A conversion. It has alot of features for configuring XO slopes, time delays, etc and at $400.00 it might be a great bargain. I'll probably buy one myself eventually just to see what all the hype is about. I bought the Ashly as a middle of the road option - it's probably not as good sonically as the comparable Marchand, but probably much better than the DBX or the Behringer...I'm just going by reviews I found on the net, so take that with a grain of salt. 🙄
XLR/RCA adapters -
If you're not too anal about wires, you can buy the cables already made for cheap. I picked up 6 male XLR to male RCA and 2 Female XLR to male RCA cables from Cables To Go for less than $60.00 shipped overnight. If you want to use your own RCA ICs you can buy just the adapers for the XLR ins and outs - XLR on one end and RCA on the other for about the same price. It's not a big deal or expense unless you feel the need for a name brand like Cardas.
Good luck.
Allan
I can't tell you whether active is better than passive - I suppose there might be reasons for using both. I like active XO's for a couple of reasons:
1) I like high sensitivity drivers/speakers and I'd rather not see anything between them and the amps. I agree with kingdaddy regarding distortion and dynamics - I'm not much of an audiophile, but what I hear in my own system between active and passive is quite a large difference. Whether you'll like the difference of course, is up to you.
2) Flexibilty - I like building speakers but I don't particulalrly like messing with electronics. 😀 The flexibility that an active XO gives me is worth it just for the lack of hassles vs getting a passive XO right. I just bought a 7 channel amp from Outlaw (sounds pretty nice with music) and along with an active 3-way XO, I can push 6 drivers from a very compact package and just dial the XO points in. I have some gain control for each frequency band (input and output) as well as response control for the XO piont itself. The simplicity of it when you're building a multiway system(s) is hard to beat.
Budget XO's -
I've only used Marchand XM1's up to this point but I'll have an Ashly 3-way in here this week. I suppose these are both budget units ($400.00 on sale for the Ashly and $30.00 each for the XM1 kits) compared to the more expensive Marchands at twice the price of the Ashly. Behringer makes a 3-way for ~129 bucks (CX3400) and the DBX234 is around $200.00. Behringer also makes a digital 3-way if you don't mind the A-D and D-A conversion. It has alot of features for configuring XO slopes, time delays, etc and at $400.00 it might be a great bargain. I'll probably buy one myself eventually just to see what all the hype is about. I bought the Ashly as a middle of the road option - it's probably not as good sonically as the comparable Marchand, but probably much better than the DBX or the Behringer...I'm just going by reviews I found on the net, so take that with a grain of salt. 🙄
XLR/RCA adapters -
If you're not too anal about wires, you can buy the cables already made for cheap. I picked up 6 male XLR to male RCA and 2 Female XLR to male RCA cables from Cables To Go for less than $60.00 shipped overnight. If you want to use your own RCA ICs you can buy just the adapers for the XLR ins and outs - XLR on one end and RCA on the other for about the same price. It's not a big deal or expense unless you feel the need for a name brand like Cardas.
Good luck.
Allan
Re: Re: Re: Active crossover questions?
I also made an XM44 (just 2-way). Its a lot of soldering, but it is a very flexible design. Bit pitty these frequency boards and so on are just a little too expensive for mere experimenting (of course you might go for the MOX design, I have the PCBs).
But Phil Marchand also gives great service.
Btw personally I think the advantages of active xovers are biggest in the low pass section. I only plan to use it to seperare the bass from the mid. mid/high will be passive
kingdaddy said:
I also made an XM44 (just 2-way). Its a lot of soldering, but it is a very flexible design. Bit pitty these frequency boards and so on are just a little too expensive for mere experimenting (of course you might go for the MOX design, I have the PCBs).
An externally hosted image should be here but it was not working when we last tested it.
But Phil Marchand also gives great service.
Btw personally I think the advantages of active xovers are biggest in the low pass section. I only plan to use it to seperare the bass from the mid. mid/high will be passive
Re: Re: Re: Re: Active crossover questions?
Nice job on the kit, it took me a full day to finish my 4-way. I think you're really missing out on something by not trying to cross the Tweeter/Mid with this, IMO it makes magic compared to passive. I had to use a XM26 (tube x-over) power supply on mine, the stock one would not handle all the op-amps.
Duck-Twacy said:
Nice job on the kit, it took me a full day to finish my 4-way. I think you're really missing out on something by not trying to cross the Tweeter/Mid with this, IMO it makes magic compared to passive. I had to use a XM26 (tube x-over) power supply on mine, the stock one would not handle all the op-amps.
A 4-way in one day is very fast, given the number of components. Hope you had good ventilation.
Btw crossing at 90 Hz, makes me curious what speakers you use.
I see you don't have the silver mica caps Marchand is using today. I got mine from Marchand (on request) half year or so after I bought the kit. First he wanted to send them to me for free, but I didn't wanted that. Than he quotes me a very low price for 20 silver mica's (a few dollars). Only shipping does cost that 😉
Btw crossing at 90 Hz, makes me curious what speakers you use.
I see you don't have the silver mica caps Marchand is using today. I got mine from Marchand (on request) half year or so after I bought the kit. First he wanted to send them to me for free, but I didn't wanted that. Than he quotes me a very low price for 20 silver mica's (a few dollars). Only shipping does cost that 😉
Duck-Twacy said:
Well as I said I cheated and did it at work where I'm well set up for PC board assy, and I've spent many hours stuffing boards fare more complex then anything like this, so it was easy.
the 90Hz crossover point was originally for the mid/woofers (SS8530-K00) hi-pass but that didn't work out very well, so I ended up with 40Hz. I bought a dozen extra plug in cards and made many extra for testing. So far I've tried 1st, 2nd, 3rd and 4th order slopes at many x-points, but I like the 4 pole the best.
Okay guys, thanks soooo much, i am getting some really good information here... I am currently working on boxes for a push-push design with 2 x FE206E's and JP 2 per enclosure. I am really thinkin active. So if i get an active crossover (probably ashly or behringer), and get some XLR to RCA conversion cables or whatever you call them. How would I need to wire the connections to speakers, amp etc.
I wanna run the rear firing fe206e all the way up, and front firing one crossed as high as possible to work with the JP2.. So suggestions on which unit to buy, and how to go about wiring the same. I can use integrated amp or tube amp/tube pre-amp combo..Have both, and both sound good to me.
Please make sugggestions.. Would like active crossover (decent) for under $500.00, and cables not to exceed $150.00 -IF POSSIBLE!
Thanks again for the input guys! I REALLY APPRECIATE IT!
Jeff
I wanna run the rear firing fe206e all the way up, and front firing one crossed as high as possible to work with the JP2.. So suggestions on which unit to buy, and how to go about wiring the same. I can use integrated amp or tube amp/tube pre-amp combo..Have both, and both sound good to me.
Please make sugggestions.. Would like active crossover (decent) for under $500.00, and cables not to exceed $150.00 -IF POSSIBLE!
Thanks again for the input guys! I REALLY APPRECIATE IT!
Jeff
Oh yeah.. I dont really think I am up to DIY active XO just yet.. Maybe soon though.. So commercial product better for me at this time.
Jeff
Jeff
http://www.marchandelec.com/specials.html seems to fit your budget - no adapter cables required. You can save a little if you do the soldering yourself, its really not that hard. note that the sale ends 7/31 I haven't used the XM9, but I have heard it it decent sounding. Of course when your confidence grows you can tweak it.
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