Active Crossover

[Will Meyer 2,374]

I've been thinking about using an active crossover for several months. I recently came across a pair of Yamaha F1030 active crossovers, and I almost got them but somebody beat me to them.

 

I know to use an active crossover, you need a seperate amp channel for each driver and the power amp is connected directly to the driver. You also need an active frquency divider after the preamp.  

 

I noticed most of the active unit are hardwired for their crossover frequency.  The F1030 was nice as since you can dial in the frequency, allowing me the option of experimenting with several speakers. As far as speakers go, I have several sets of 2 and 3 way speakers that I could add additional binding posts and a set of switches to bypass the crossover so I could use them on a system with an active crossover, or a conventional system that relies on the speaker's internal crossover.

 

Anyone have any experience with this route?

Any recommendtions on a reasonable brand/model of active crossover.

Again having a unit that I can dial in frequencies would be important. Many dedicated units are done via hardwired modules - looking at the schematics, some of them are resistor packs.

 

[BarryG 2,853]

I had a dbX crossover with my Maggie’s, it worked well.  I also played around with it on the als hybrid speakers.  I was happy with the results.  
 

I sold it a while ago, keep in mind, most have balanced Xlr connectors.  So you might need to figure a conversion scheme!  
 

I  am planning on finishing a Marchand  crossover I have in parts under my bed one of these days!  
 

It’s fun to experiment, one of many joys of this hobby.

[Daddyjt 9,585]

For flexibility, you can’t beat a “mini-dsp”.  Completely programmable via laptop to be crossover, parametric eq, etc.

 

https://www.minidsp.com/products/minidsp-in-a-box/minidsp-4x10-hd

 

the basic for a 2way system:

 

or go the full 9 yards:

 

 

[Will Meyer 2,374]

I was looking at a dbx-234s.

It's around $200 new - If I hunt I might find a used one.

It uses 1/4 inch plug-ins so I can use a standard adapter for RCA plugs.

The unit will support stereo 2way, stereo 3way, or mono 4way (I currently don't have any 4way speakers). The Yamaha F1030 required 2 units to do the same thing.

 

Daddyjt - I will research the DSP. It looks interesting.

 

BarryG - I'm interested in your application with Maggies. I have a set of SMGa's, MG-12qr, and I waiting on a set of LRS (which have been on order since May 2nd). I play around a lot with conventional crossovers, but I haven't been able to bring myself to opening up the socks on the Maggies. Was the modifications to support an active crossover difficult? I notice many people pull the crossover and mount it in separate box. I could see the advantages to support larger poly caps and inductors in a passive crossover, while allowing it to readily pulled out of the circuit for an active crossover.  

 

[kve777 6,881]

What problem are you trying to cure?

 

My experience is that EQ's, DSP's and Active crossovers are fine for PA systems, but tend to destroy things I like in sound reproduction, ie. Imaging, Soundstage and Impact. So, if you wish to use such things, flying in the face of professional speaker designers, what is your goal? What is wrong that you are trying to right? If you just wish to experiment, fine, I get that. Just make sure you do not do anything that can't be reversed inside your speakers. BTW- blown tweeters, mids and woofers are a reality you should expect to deal with. Crossovers protect drivers. Without them, you are on your own to create a protection plan. State your goal, and We can help you proceed.

[cuda 523]

I love active systems really brings out the music, where are you located Will? Usually you get what you pay for on dsp's Really cheap ones are bad PA units, expensive ones are musical and medium priced fall right in the middle and can go either way.

[Will Meyer 2,374]

I agree with the philosophy of don't do anything you can't undo.

 

The general reading is that active crossovers improve sound dramatically in a speaker. The reasoning why there aren't alot of them out there is that its three or four times more expensive than a passive crossover. For example, on a 3 way system, I'd need 3 power amps, and an active crossover. However, the advantages are phase alignment. Every inductor changes the phase of the signal, as well as every capacitor (in the opposite direction of the inductors). Additionally, the matching and blending of the drivers are limited by the slope of a passive crossover.  The third factor is the low-pass, band-pass, and high-pass circuits use the speakers natural impedance as an integral part of the filter's functionality, yet the impedance of all speakers change at different frequencies. It's not unusual for a 6ohm to vary between 25 to 2 ohms depending upon frequency.

 

By using an active crossover, all these issues are adverted.

 

Granted, they are more complex to setup.

Paul McGowen (PS Audio) states all manufactures would perfer to build speakers with active crossovers, but the consumer market won't support it because of the cost/complexity.

 

My interest is largely academic. The pros/cons are straightforward but I'd like to experience the difference and evaluate it myself.

 

Its not a problem I'm trying to resolve. This site is my major source of experienced audiophiles and technicians.  I'm interested in hearing what their opinions and experiences are.

Edited August 11, 2020 by Will Meyer

[Will Meyer 2,374]

Btw...  I'm in the Seattle, WA area.  Marysville, WA - just north of Everett.

[cuda 523]

That's what I thought, I have a couple Yamaha electric x-overs I bought off ebay because dr markie recommended them for apogee and carver and infinity hybrids. But they seemed overly complicated and I never really used them, anyway you can have them for free if you want I am near I-5 by the UW in wallingford.

Edited August 11, 2020 by cuda

[Will Meyer 2,374]

Awesome!

 

I'll pm you and share contact info.

 

Thanks!

[kve777 6,881]

I actually have a Pioneer SF-850, a highly regarded Active Crossover. Just haven't played with it much. Maybe I should recap it and experiment.

[Daddyjt 9,585]

Another thing to consider with Switching to active crossovers is the fact that many passive crossovers incorporate notch-filtering to address driver and/or enclosure resonances/anomalies.  Replicating then via DSP is rather straight forward if you can determine what frequency and the amount of gain/attenuation is needed. 
 

The “magic” of many speakers lies in the crossover network - be advised that there is more to most crossovers than just frequency filtering.  That said, providing you don’t exceed the physical limitations of the drivers (tweeters and mids), you likely won’t damage your speakers... but the results may be far from ideal sonically....

 

at any rate, there’s no harm in trying:-)

[Will Meyer 2,374]

That Pioneer is a nice looking piece of kit.

 

I thought it would be a good experiment.

I have a set of Boston A70s that I plan to start with.

I'll put a switch to bypass crossover so I can go back readily.

 

Its a 2way, so its should be relatively easy to setup.

If the results are promising, I'll try it on one of my 3ways.

[jazzman53 1,275]

Here's what you REALLY want.  Add a microphone for the auto-EQ and you're ready for anything.   I've seen used ones on Ebay for as low as $150. 

 

 

[AndrewJohn 10,417]

1 hour ago, jazzman53 said:

Here's what you REALLY want.  Add a microphone for the auto-EQ and you're ready for anything.   I've seen used ones on Ebay for as low as $150. 

 

 

 

That's what I was going to suggest, or something similar,...   The later DBX DriveRack Venu 360 takes this to the ultimate... Some here on the forum have used the Behringer version of such a unit..., and there are many others.  But DBX, under the Harmon brand, with the Venu360, seems to have really taken this to a whole new level.  Understand that most of the applications for these are "pro audio", but the savvy audiophile knows how, or is adventurous enough, to apply it to one's audio listening room set-up.

 

Combine this with a Rane Balance Buddy 44x with the upgrade to a double "88x" (fills out 5, 6, 7, 8 in the rack unit, in pic below) Balanced-to-RCA multi-channel converter (modify the input gender with a new connector) and you have something with ultimate ease of use and flexibility... (pick this up cheap on Ebay...)

 

Pricey, yes - about $800 for a NEW DBX Venu360, but I've seen B&H Photo sell rental (one-time-use) units for $400 on ebay...

 

The PC/Laptop/i-Pad user interface takes the UX experience to a new level of ease, along with the microphone for near "automatic" setup..., call it "Auto-Magic" (my word for it).

 

I think there's even a thread here on the forum from some legendary members, as well as a currently-sandboxed member... (found a few below for you...)

 

Here's the promo video for the DBX DriveRack Venu360:

 

I dug up a few threads that will blow your mind..., fill it with all kinds of questions, and set you on a quest to the way-beyond..., lots of history on our site about this topicl 😉

 

 

 

 

 

 

[Dadvw 2,875]

Nice post AJ! Enjoy the ride down the new rabbit hole Will......grin

[jazzman53 1,275]

I'm currently feeding my Transporter's AES out to a DBX V360, which is almost too good to believe. 

[xavionics 2,067]

Going with an active crossover can be a challenge to say the least.
When I built my current speakers, I committed to active crossovers.

Here are my experience with the three crossovers I’ve tried:

 

Rane AC22. Purchased used

Pros - cheap (<100 bucks on eBay)

can change frequencies on the fly.

balance the highs and lows on the fly.

Cons - a little noise in my system.

No adjustments for slope.

Overview - a good Inexpensive option for Experimentation.

 

Mini-dsp 2x4. Purchased new

pros - cheap.

wildly flexible with crossover frequencies, slopes, notch filters, etc.

Cons - I don’t think it can be adjusted on the fly (I could be wrong here)

I found the sound to be grainy

Overview - another good, inexpensive tool for experimentation. Very powerful tool if you wish to design your own passive crossovers.

 

Marchand XM-9. Purchased new

Pros - reasonably affordable.

clarity and detail far exceeding the previous two setups.

Ability to match the highs with the lows if pots are added.

Baffle step compensation is easily added and instructions are provided.

Cons - expensive if you buy one pre-built. 
frequency changes only via resistor networks

slope changes require modifications to the board (instructions are included)

requires an enclosure of some sort. 
requires a +/-15 vdc power supply, available through Marchand for a reasonable price.

 

I would love to try the dbx DriveRack 360, given the great feedback I’ve read. 
one day I’ll decide to pony up the money and get one to play with.

But for now, I’ll keep the Marchand in the system. 
 

 

 

 

[EAHBuckeye 238]

I find this info very intriguing to say the least! I attribute my bi-amping/active crossover failure last year, to my novice/ignorant status. I attempted to bi-amp my ADS 910's with an SAE 4000 2-way active xover, using one M500t, MkII and a stock M500t. Sounded like crap compared to the single amp with the speakers passive xovers. Now the SAE, bi-amp cards and stock M500t are dust collectors.

 

I have notions of re-attempting this some day, but not sure it'll ever happen realistically.

[B-Man 4,779]

Well, by looking through this thread you can see there are a few others that have successfully deployed active crossovers in their systems. You might as well pull that stuff out, knock off the dust and get to work !! You should get plenty of help via posting in this thread - and by posting pictures along the way. People here LOVE pics.

 

The main reason we have a "no boobies" picture policy here is because Greg is a humanitarian - 3/4 of the members would collapse from dehydration caused by continuous staring and licking of their monitor if a picture of a nice set were posted. 😲 

[AndrewJohn 10,417]

14 hours ago, xavionics said:

[...]

Marchand XM-9. Purchased new

Pros - reasonably affordable.

clarity and detail far exceeding the previous two setups.

Ability to match the highs with the lows if pots are added.

Baffle step compensation is easily added and instructions are provided.

Cons - expensive if you buy one pre-built. 
frequency changes only via resistor networks

slope changes require modifications to the board (instructions are included)

requires an enclosure of some sort. 
requires a +/-15 vdc power supply, available through Marchand for a reasonable price.

[...]

 

If I were a smarter, and wealthier audiophile... (OCCD has destroyed much of the common sense I once had... LoL!),

 

(I'm really off the charts on enabling, here..., but it's fun ! )

 

I would like to someday dive in after figuring out the optimal crossover points with a miniDSP, or other unit with an automagic microphone type set-up..., for my specific room characteristics..., and invest in Marchand's Tube Crossover, the XM-126..., Why?  'cause it's Tubes, man... 😉  https://www.marchandelec.com/xm126-tube-electronic-crossover.html

 

Lee @xavionics is to blame for this desire that possesses me... 😉 

 

 

 

 

[KPT 75]

On 8/10/2020 at 8:56 PM, kve777 said:

 

BTW- blown tweeters, mids and woofers are a reality you should expect to deal with. Crossovers protect drivers. Without them, you are on your own to create a protection plan. 

 

This is incorrect. I've blown too many tweeters to count with passive xovers. I've blown none with active. Pair a low watt amp amp with them and set your processor correctly and it is much better than a passive xover. 

[B-Man 4,779]

1 hour ago, KPT said:

 

This is incorrect. I've blown too many tweeters to count with passive xovers. I've blown none with active. Pair a low watt amp amp with them and set your processor correctly and it is much better than a passive xover. 

 

Your experience is obviously different than Kevin's. However, it does not mean his experience is "incorrect". I can assure you - connect a DSP "tweeter" output to a Carver amp, play a "spirited song" and give me a few Jack & Cokes beforehand and you will definitely see smoke coming from those drivers.

 

If you were blowing tweeters with passive x-overs you were most likely clipping your amp. Using an active x-over will allow a smaller amp to play louder than the same amp driving through a passive x-over. Perhaps that is why you didn't blow them with the active x-over - you could achieve the volume level you wished for without driving the amp into clipping?

[aceman117 723]

16 hours ago, KPT said:

 

This is incorrect. I've blown too many tweeters to count with passive xovers. I've blown none with active. Pair a low watt amp amp with them and set your processor correctly and it is much better than a passive xover. 

On my DBX PA2,  I set the limiter threshold to protect all my drivers on my Bi amped Silvers....no blown drivers yet, even with the system cranked to the max at times...

Nice option to prevent driver damage!

 

[aceman117 723]

15 hours ago, B-Man said:

 

Your experience is obviously different than Kevin's. However, it does not mean his experience is "incorrect". I can assure you - connect a DSP "tweeter" output to a Carver amp, play a "spirited song" and give me a few Jack & Cokes beforehand and you will definitely see smoke coming from those drivers.

 

If you were blowing tweeters with passive x-overs you were most likely clipping your amp. Using an active x-over will allow a smaller amp to play louder than the same amp driving through a passive x-over. Perhaps that is why you didn't blow them with the active x-over - you could achieve the volume level you wished for without driving the amp into clipping?

Agree... Also, as a side note, always use a larger amp to prevent clipping which destroys drivers. More headroom is always best.

Edited August 14, 2020 by aceman117