Go Active Crossover or Upgrade existing XOs?

It was recently suggested to me that rather than doing a crossover upgrade 

I look into an active crossover for my Tannoy FSMs. Anyone experienced enough 

to guide me? What advantages does active provide?


An active crossover is implemented before the power amplifier so you need to have an amplifier for each driver. For this reason it is also referred to as Bi-Amping, Tri-Amping etc.

A speaker with a passive crossover can present a complex and difficult load to the amplifier, taking into account the impedances of the drivers along with the inductance and capacitance in the crossover network. In most cases active will be a significant improvement. There's a good article here that describes in much more detail.

Another advantage of active is that you don't need the enormous (and expensive) components required for passive. I'd suggest seeing if someone has already designed an active crossover for your speakers.

Just to be clear I'm talking about active analogue crossovers (using op-amps), not DSP based.

That’s the technical version. While technically correct, there must be something else going on, or all the world’s best cost no object million dollar systems would be doing this, and all the statement speakers would be designed for it. Which, wait, what’s this? None are? NONE?!?!?!

Right. And if its none of the cost no object stuff then it can’t be they aren’t doing it because it costs too much. At a certain level the more it costs the greater the bragging rights for being able to make and sell and own. And for damn sure active costs more to implement than passive. So it can only be that active crossovers in spite of the wonderful sounding technical explanation are actually worse than passive.

Reason number 812 on the list of why not to trust technical specs and reasons.
The issue with active crossovers is that they are not simple. You have to do everything the passive crossover does.

DSP is pretty much the only way to go IMHO when going active, but how much are you willing to measure, tweak and adjust?

Upgrading passive components is relatively simpler and harder to mess up, except when replacing electolytics.

Just pick the set of challenges you want. :)
I addressed that question in my review of the Legacy Audio Whisper DSW, a speaker that is configurable as either passive or active x-over. You can find that review at Dagogo.com 

My final conclusion was that with the same speakers in either configuration I was able to make either passive or active outperform, entirely dependent upon the ancillary electronics and cabling. As close to a perfectly uniform comparison as possible showed that active is slightly superior. However, change the electronics and cables, and the results are shaken up once again.  

As much as some people might think that an active speaker system is inherently superior, I did not find that to be the case in my comparisons. 
There has been a long running conspiracy to prevent active technology from entering the hifi marketplace as it would put all audiophile amplifier manufacturers out of business. Same reason we dont see speaker tuning services as it would put many speaker companies out of business. 

So do not be duped into believing that just because the so called state of the art speakers arent active, active crossovers must be inferior. Now you know the real reason we dont see them.

The advantage of active is that you can become an overnight armchair crossover designer. No messy soldering and endless swapping of components required. You can choose what slopes you want and achieve them instantly whereas with passive, you need an anechoic chamber and state of the art measuring devices which few audiophiles have.

I don't know why active loudspeakers haven't caught on in the consumer market, but there are many examples in recording studios. I have some active Genelec monitors which sound great as nearfields although they won't be to everyone's taste. 
Technically the benefits are compelling, but I understand why people might be sceptical given the enormous amount of BS in the audiophile world. Siegfried Linkwitz' LXmini speakers can be paired with Nelson Pass designed active crossovers... admittedly not that mainstream but I'm yet to read a bad review - and they're designed by two people with some 'audiophile' kudos.
I agree with @erik_squires that active crossover design isn't that intuitive but it really isn't much more difficult than passive as long as you don't try to iron the frequency response completely flat with endless filters.
If you're starting from scratch then it would probably be best to reverse engineer the existing crossover (or get someone to do that for you) and model it in DSP to use as a starting point. You can then make adjustments in software before re-creating the filters using analogue components (or getting someone to do that).

I'll go with Eric on this one. Digital cross overs is absolutely the way to go especially if all your sources are digital. We can argue about analog later.
You can do almost anything you want in the digital world without distortion. Using digital cross overs and multiple amplifiers makes the most sense if you are making your own speakers. It gives you total control of the situation and if you have a good room control system you can measure the results. Millercarbon you are wrong here. Many manufacturers give you the opportunity to bi amp. Magnepan and Wilson do this. The famous Levinson HQD system was tri amped. 
Gadios, It all depends how you do it. Implementation is everything and it will cost you some money. It is possible you might be better off just getting new speakers. If you like playing around and experimenting great but, if you have not got a way to test what you are doing you might wind up out to sea without a compass. If you like your speakers you might consider getting a new amplifier. 
I agree with @erik_squires that active crossover design isn't that intuitive but it really isn't much more difficult than passive

And passive crossovers are difficult to do right!  :D That was kind of my point.

Anything is possible with money and time.  But then with too much money and time will lead to hubris.  And that's why God created men and women.  

OK, enough hubris from me.  
From your question it's obvious that you don't have the technical skills to start from scratch using any kind of active crossovers. To get it right is a complex process even for an experienced person, my recommendation is to leave it alone and save yourself time, money and frustration! 

From your question it's obvious that you don't have the technical skills to start from scratch using any kind of active crossovers. To get it right is a complex process even for an experienced person, my recommendation is to leave it alone and save yourself time, money and frustration!
Give the guy a break, will you!  He may actually know more than you.
Listen fellas, its not just a river in Egypt, okay?

Still waiting to hear, if its so great, why all the world’s greatest cost no object systems aren’t doing it?

I mean, its not like there’s some vast audiophile industrial complex conspiracy to... Oh wait, what’s this?

There has been a long running conspiracy to prevent blah blah yada yada


My experience: I've gone active and very happy. In my experience, given a certain (limited) budget, I've gotten better sound by optimizing: focus on an audiophile PC as sole front end, run digital crossovers, a multichannel DAC, keep my tube amp for mids/treble, and a cheap Hypex UcD amp for mid bass and Rythmik subs for lowest frequencies. The tradeoff: steep learning curve, VERY involved vs just plugging an amp to speakers with passive xo. The biggest trick is building your own active speakers and selling your existing speakers with the expensive passive xo. 

I suggest you do a lot of reading before deciding. Search in computeraudiophile a couple of articles named Acourate walkthrough, and advanced Acourate (or something along the lines) to learn how digital active xo could be implemented. 

I hope this helps. 
I had bi-amped my JBL 4333’s which were originally designed with a bi-amp crossover (though I had built my own crossover using Nelson Pass design for mid/hi and used a Rane active to separate the low frequencies for my woofer). I used vintage amps with solid-state MAC 1750 on bottom and Dynaco tube on top. I thought it sounded good until my tube top end went out and I thought it was cheaper to just finish the passive crossover for the woofer Than repair my Dynaco. Wow!  So much better with just the Mac powering everything. 
Granted, I was using less-than-state-of-the-art equipment and I bet it would have sounded great if I had the flexibility to try multiple amps top and bottom until I found the perfect combo. But that would be a lot of money and a lot of experimentation. 
If you’ve got the time and money, it can be fun to tweak, but for me, simplifying by getting rid of all the unnecessary hardware in the signal path gave me a much better sound. And Nelson Pass designs a pretty good passive crossover too. 🤓
My general answer to this would be: If it is a 1.st order filter, upgrade it, if it is 2.order or moore skip it and go active. 


Go Active Crossover or Upgrade existing XOs?

It was recently suggested to me that rather than doing a crossover upgrade

I look into an active crossover for my Tannoy FSMs.

I tried With my ML Monoliths+plasma’s to have active xover on the ESL/plasma and active xover on the bass.
Even with very expensive active xovers on the ESL/plasma it still didn’t sound as good as the well made passive it came with, just sounded sterile with a slight lack of body and warmth.
But the bass was better with the active, rather than passive.
So I had 18db high pass 180hz> passive for the ESL/plasma and 24db low pass discrete active 180hz< for the bass.

BTW: I even tried doing it all digitally and it was even more sterile on the ESL/plasma almost like missing harmonic structure, surgical would be a good call.

Cheers George

It's an interesting game.  But I'll bet most arguing about this do not live with fully active monitors or floor standers with a serious front end.

Well done fully active is plainly scary in its immediacy, impact and timbre.  I do run active with ATC 40A speakers and anybody who has sat down for a listen has walked away shaking their heads.

I did listen to the current KEF Blades run properly and was very impressed,  However, the price of entry retail for the set up was closing in on 100K.  I had heard the same pair improperly run with cheaper amplification and they were a disaster.  

The properly matched amplification, cabling and PCs for the amplifiers a terrific investment.  Nearly all of this is taken care of with actives which properly match the amplifiers and eliminate crossover problems.
I might add that my ATC 40 actives came by way of a shop I've worked with for years.  I agreed to leave the speakers in the shop set up for two months before taking possession so that they could expose clientele to them and possibly pick up the line.  

The report was that everyone was overwhelmingly impressed and yet the owner reported customers are not ready for active.  They cannot leave the customary source- preamp- amplifier- speakers template.

Each listener was knocked out, but could not go the active route.
Well from somebody that has always had speakers with passive crossovers, I recently have been introduced to the world of active crossover enables Line Array speakers , and I cant be more happy with the performance, soundstage and overall simply floored response that my ears are treated to every time I listen to them.
   As someone mentioned before , active crossover is mainly used in the home made speaker application, such as my Array system which consists of 28 6.5" woofers and 28 piezo ceramic tweeters in each tower, which were designed and built by a competent electrical engineer (done properly, not a kit per say), the option to adjust and calibrate the frequency, gain of each channel is pretty simple and rewarding to say the least.
    And yes they are bi amped, with A REL sub woofer.
 There are many active crossovers in the market to choose from , dbx, Samson, Ross power, couple older Nakamichi systems and so on, the one I choose offered many features such as phase control for each channels outputs, mute for each ouputs , delay and threshold limiter etc. all using balanced connections but also available in unbalanced versions to match your equipment. All for under $300.

Don't be scared to venture into the unfamiliar, you might be surprised at what you have been missing.

Wow, now that was group of very well laid out responses. 
-Millercarbon's point is not something that can be ignored.
Perhaps most speaker manufacturers just don't want people
adjusting the sound they worked so hard to create?
-dicarmeli exposed me for the ignoramous I am in this endeavor.
But I can try to learn about it.
-Unfairlane's point sounds reasonable. I will find out what order 
I'm in. 
-Lewinski's advice is to learn more, then decide. Wise.
-George's work was for naught.
-I like the way Piazanno put it best. Go For it!!!
@pizzano may I ask which technology you used for about $300?

IMO there are many speakers with passive crossovers indeed but just a small amount of these are implemented right, that's why there is an aftermarket modding it. There are many challenges with passive (impedance changes, phase etc) that only experienced designers are able to make it work and this represents adding more elements in the signal path and with digital dsp advances, passives will fade eventually.

Answering directly to the OP @gadios, I will definitely experiment with active or active digital if budget allows it (and time too). In my specific case my speakers have passive crossovers but to my ears I like to think are well designed.

I am not an EE, or audio speaker or amplifier designer, just another guy who likes music reproduced in the best way possible.

Depending on the number of drivers you have (remember you'll need an amplifier channel for each one) you could look at one of the MiniDSP solutions. If you have three way speakers and are on a budget you could start by replacing the Mid / Bass crossover and leaving the Mid / High intact which would require a DSP with four outputs and four channels of amplification.
Please remember 85% of Xovers in speakers unless very $$
are substandard.i have been modding Xovers and internal electronics for over 25 years. The Xover parts usually at best have solen capacitors or the China specials Keven speakers at $10 k +
shocking but true I had a 15k Martin logan ,and Sonus Faber 
both had the lower quality white mundorf evo caps.
in your Tannoy he Jupiter copper foil would be excellent 
and use the worlds best resistors from path audio.for my audio get together I demonstrated a experiment a stock monitor audio studio speaker, and one I added $1000 in Xover parts upgrade
it went from a $1500 to a $5k speaker in sound quality vs several 
well known speakers . The Xover is the brain,or heart of all speakers, also buy good WBT Copper connectors not the junk 
gold over brass which comes with most speakers .brass is horrible in natural fidelity vs Copper and has 4 x the resistance = distortion 
i spent literally 1,000s of hours listening and comparing .i usually also replace the cheap internal wire as well as jantzen a Copper inductors . When using a electronics active Xover you can tune it but it looses the flavor of the great capacitors which adds that depth and live presence Lon paper a active is more ruler accurate 
thst applies to solid state vs vacuum tubes in accuracy but 
having a vacuum tube in the circuit adds another dimension in realism. Your ear is the final word in tonal accuracy thst is whst I rely on more then just measuring equipment ,which is just a guide or starting point. After 40 years in Audio and having owned a Audio store .i have had pretty much most things out there learned from many excellent techs on modding .that is why modding 
gives back so much more per $$ dollar spent in fidelity vs just buying new ,for rule of thumb  25% or less  of the product cost actually goes into the parts ,the rest overhead,R&D,and overhead!!

I've been running an active crossover system for nearly thirty years using four ARC amps. Two mono blocks for woofers and then two stereo amps for the mids and highs.  Probably the greatest advantage IMHO is that none of the amps "know" or could care what any other amp is doing. Tons of headroom. If you like to twiddle the knobs its Christmas everyday!  Plus really fun to only run the bass amps to tune the room etc etc. 
The new PS Audio AN3 is a bi-amped system and sounds amazing to me. Arnie Nudell's large systems were bi-amped as well.  Does anyone remember the M&K sub-woofer satellite system way back in the day? BTW, the ARC room at RMAF was a true bi-amped system using three
ARC amps, two mono blocks and a stereo amp powering Sonus Fabers.
All analog system, no digital in the room.  To the OP I say "jump in the water is fine". 
I think mijostyn1 and barts28 made salient points.  Audio Research sold both active and passive crossovers early on when they had a co-marketing agreement with Magnepan.  (Some may be interested in learning that Diller was with Johnson at AR way before he went over to Winey's company.)

The passives were available in a few varieties and the actives, which sell for TONS of money today, were also either 2 or 3 and came in several varieties.  Back then, Magnepan wanted you to tri-amp the speakers and Audio Research wanted to sell you many amps, so we sold and set up these systems for customers.

As I remember, and it was 40+ years ago, so take this with a grain, the actives were easier to set to the room than the passives, but both worked rather well when set up properly--most good equipment does.

As to which is better, I would (if I were doing this today) probably go active and put as many amps as possible (barts28) in the system.  If you have Maggies, they eat power, so more is always merrier if you like to crank up Mahler or Zeppelin or whatever.


@audioman58 from your post would you recommend the Jantzen audio inductors or if not which? I was under the impression their foil inductors were very good but again you've been an expert in this area I rather have your opinion
This is a bit of an ad-populum argument, but not completely without merit. The boutique companies that build "statement" speaker products are likely often lacking the technical depth/resources to build an effective and superior active cross-over. As well, they still need to sell what the market wants, and that market wants their expensive and highly visible amplifiers hooked up to their expensive and highly visible speakers. The market also wants "analog" inputs, and the best active cross-over will be full digital.

millercarbon2,169 posts12-09-2019 11:51amThat’s the technical version. While technically correct, there must be something else going on, or all the world’s best cost no object million dollar systems would be doing this, and all the statement speakers would be designed for it. Which, wait, what’s this? None are? NONE?!?!?!

"Statement" studio monitors do have active cross-overs, and their users are quite critical.

But, the reason not to (or to) use a passive cross-over is for technical reasons, just the right ones. With purely an active cross-over, you have a direct connection to just the driver, and typically with high damping factor. There is an assumption made by some (many?) that this is ideal. That is not a good assumption always ... for technical reasons. Purely analog active cross-overs are typically limited in complexity (like their speaker correlates). Digital cross-overs are unlimited, though stock cross-overs and firmware only touch on what is possible with advanced signal processing which can do things that no analog cross-over, active or passive could ever do, especially integrated in design with a purpose built amplifier.

So ... you can play and tweak a digital cross-over, but without having adequate equipment to verify your results, you are likely going to just fix one problem and create another, till you fix that problem and then create another. Listening is final tweaks. You need measurements to get close, and for speakers, they really do matter. I would just rebuild the passive cross-over unless you are prepared to invest serious time (and money).

Personally their wax paper foil inductors are the best,
but for bass I prefer a open foil coil depending on application
locally cannot get them I order from Hifi connection in theUK
fedex 3 day is only $30, and they carry the Path audio resistors 
,parts connecxion in Canada has a25% sale  so if they have the values you need in stock go there ,and overnight saver,ups is only $15 under 3-4 lbs for specifics email be I will try to assist you.
The Bryston room at RMAF was bi-amped active external crossover as
well. System sounded great.

I had forgotten about the Levinson HQD system: Hartley, Quad, Dahlquist.  Amazing system, you have to have the dedicated space for it though, it was rather large to say the least.

Digital cross-overs are unlimited, though stock cross-overs and firmware only touch on what is possible with advanced signal processing which can do things that no analog cross-over, active or passive could ever do, especially integrated in design with a purpose built amplifier.
Surely they have no side-affects?
With a digital input, only the side effects you intend, which any speaker is going to greatly swamp.
With a digital input, only the side effects you intend, which any speaker is going to greatly swamp
There is no crossover that is perfect, not even an active digital crossover. Although speaker systems almost always have distortion many, many times greater than a quality audio component, that does not mean that the speaker system will not reveal faults in those components. What you wrote is a bit ambiguous, so perhaps that’s not what you intended to say.
With a digital input, only the side effects you intend, which any speaker is going to greatly swamp.
Hey, can I go with "DSP" and live happily ever after?  

...all of this seems terribly familiar...and recent, as well...;)

HO...going 'active' does not have to require massive amounts of $.  It will necessitate multiple amps, but it will allow you to 'mate' wattage to the drivers involved....more power to the woofers?  Not a problem.  Back off on the tweets?  Same deal...

Gots passive speakers?  Are they out of warranty?
Do you own a screwdriver?
Make notes on the wiring, check the stated xover frequencies, peruse the type/design of the existing passive unit.
Run jumpers out of the port, if there is one.  Otherwise....surgery, some minor manufacturing, wiring....

Set the xover to 'type of'/points/slopes....start with the 'originals', and then dial to taste....or displayed responses...

You will spend more $ on cables....goes with the territory....

You can make it all sound as described above. *S*

You can also make it all sound like thrice-eaten cabbage....

But...that's the wonder and horror of Control. ;)
....Badges?!  What/When/Where....?
*sigh*  Time to light up Photoshop....again....*grumble*
To the OP, it's a complicated question with no single, clear answer as you can tell from the replies. 

I happen to prefer digital active (since I like the experimenting) provided you can fall back on some kind of power treatment to ward off any digititus. But, that's just me. Others might greatly prefer good passives or good analog actives.

But, I agree it does depend on your goal. If all you want is to replicate the stock parameters, but improve the sq, then upgrading with better passive components may be all you need. 

But, if going active, the main catch is how intimate are you with how the original crossover was designed. If it can be entirely duplicated with whatever level of sophistication of your active crossover has, then you should be ok. And at that point, if you're looking to tweak the original design somewhat, you should be able to. 

One more problem, though. Passive crossover components often have a tendency to 'obscure' things a bit sq-wise and traditionally this has been looked upon in the manufacturing community as an opportunity to 'hide' (sweep under the rug) some minor details of driver mismatching...things that might become audible to you if you undo the maker's work. If it should come down to the fact that the drivers are less than well matched (and this is perhaps more common than you might think), then this might be something of an audible problem whether you are improving things actively OR passively). But, every design is different...and it may be an unknown as to whether or not that might apply or whether it might not be objectionable to you, if it does. That will have to prove to be a judgement call that you'll have to make and the only way for you to make it might be after the fact.

But, there's no real way to know (unless you know of someone who has your speakers and who's been there and done that) until you take that plunge yourself. It's not that I'm telling you that it's all a bad idea, I just mean that you should be willing to accept some risk if you're going to roll the dice on it. But who knows, it could turn out very well, better even than you might have thought, actually...especially if you're that persistent. 

But, likely you'll have to hear those results firsthand and that means that I can't make a recommendation for you one way or the other. I can only outlay, as above, what you might run into, if you choose either.
@ivan_nosnibor  , well put. *S*  And, both a warning and a challenge.

But, since most of what I've been doing lately is experimental....and nothing is 'pedigree' that I own...

Nothing ventured....;)
 ...and really nothing to lose. *G*

@andy2 , ...'muchacho' , gringo...
I have a hybrid system. Active crossover between lows and mids and passive between mids and highs.

Adding an active crossover to the system was the single biggest improvement to SQ I ever made. 

They can take quite a bit of time to dial in if you have never used one.

I find that they can be a great tool for compensating easily with variations between different recordings where one is too bright and another too dark. Mine is located right next to my listening position so I can easily make adjustments.
I have had bi-amped Maggie 1.6's with an active Bryston 10B crossover (analog) for 10 or so years. In my modest system the difference was quite astounding. As someone has pointed out, cleaner, more dynamic, and musical vs. passive crossovers. 

A caveat though. As richopp pointed out, Maggie crossovers were designed to be bi-amped if so desired and gutting the passives and rewiring was pretty straight forward. I did add new binding posts and plates when doing the conversion but could have used the stock pieces. Maggies are also known for not having the highest quality components in their passive crossovers (see the countless threads on the Planar Asylum of crossover component upgrades). Also, the Bryston 10B has settings that mimic the stock crossover frequencies and slopes, although I ended up preferring different settings.

Point is - it made a tremendous difference in my setup. Well worth the money (extra 2 channel amp and interconnects) and effort.  Not as intimidating to do as you might expect (geez, even I was able to do the conversion).

As to passive crossover component upgrades or digital vs. analog active I have no experience and can't comment.

The Elliot Sound Products white paper posted earlier on active vs. passive is excellent. Good luck with your quest.

Jim S.
Talking about "DSP" engineering an cost ... as a saying goes "A good engineer can do for a penny for what a mediocre engineer can for a dollar."  But I don't do cliche.  Nobody has ever said that an "evil engineer will take the dollar and maybe even your soul".  
I design crossovers for my speakers. I’ve designed and built active and passive. Active all the way! Oh, ANALOG 🤓
I will echo the sentiments of others who have use active crossovers to biamp Magnepan speakers.  Up until their X.7 models, they were built to actively biamp by providing an external passive crossover box that could be bypassed.

I did this with my 3.3Rs and the difference was astounding.  I don't think there can be a single rule here.  It all depends on the quality of the passive crossover components relative to the active crossover you might obtain.  If you have 2 good amps and don't want to trade those for one great one, it is definitely a good experiment.  But you have to get a decent active crossover.
I sincerely thank you all for the many varied approaches and results you
have found traveling this road.. This was exactly what I hoped to learn. I am not technologically gifted and have zero engineering knowledge.
I do recognize the wisdom of Clint Eastwood's immortal
words, "A man's got to know his limitations". From what I gleem great rewards await those who spend their lives twiddling with knobs in
the Active XO world.  I will be better off researching the best caps
etc and letting my qualified friends install them. Sad but true. 
FYI: The party suggesting the active route was none other than NP

I looked at pictures of the Tannoy FSMs. Hard to tell from pictures, but it appears to be a fairly complex passive 4-way design. On the back I see what look like 4 pairs of R/L speaker cable binding posts.

I have used a high-quality 2-way electronic crossover by Marchand (XM66) with my passive ATC SCM12 Pro monitors. I use the XM66 to split the raw line level signal into low-pass (<70Hz), going to a powered subwoofer; and high-pass (>70 Hz), going to a Wyred4Sound ST-500 stereo class D amp (w/jumpers connecting the low & high pair of R/L speaker binding posts.

The sub I’m using is a very capable, musical-sounding one for my small home office JL e110, and the ATCs are a great combination of highly resolving & musical. Through the Marchand crossover, I’m getting the best sound ever in a desktop system. Note that I also heard the ATCs direct (no active crossover & no sub), and that sound was also fantastic. I’m not sure I could tell them apart, honestly.

Marchand makes great products. For the real audio obsessive, you can upgrade opamps. I’m guessing either the 4-way XM44 of XM9 would do exactly what you need. In your case, you’ll need the crossover frequencies (which will dictate the crossover boards he’ll put in your unit).


Final note: Marchand active crossovers use either 24 dB/octave slopes (XM9 or XM44); or 48 dB/octave slopes (XM44 only). These may well be different from the internal crossovers in the Tannoys. 24 dB/octave works perfectly w/my ATCs...