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Is it time for active speakers?

Proper feedforward requires two output stages and then a way of summing them. Not normally done at audio frequencies.
 
Jonboi, I've heard a number of all in one active systems and NONE of them have sounded good enough for the price for me to want to buy them. And by good enough I mean "hearing what was on the recording as faithfully and authentically as possible".

IE the problem is not with me, it's with the all in one active speakers I've heard.

The general level and experience of hi-fi equipment on this forum is high. My speculation is that the reason that there are so many users of passive speakers here on this forum is that the active speakers they've come across have not been good enough for the price for them to want to buy them.

My speculation is that it really is as simple as that. And that in most cases passive ownership has nothing to do with a desire to tinker or to cling to old technologies, or some sort of rose-tinted nostalgic look at the past.
 
I’m not entirely persuaded that active is better than passive all other things being equal.

I base my view on experience of the ATC SCM40s, which I’ve tried in both active and passive form. TBH I don’t think I’d be able to tell the difference between the two set-ups I tried. But it’s complicated because the 'all other things being equal' clause can be tricky.

To do the comparison on a level playing field, I guess you’d have to power the passive set up with power amps that cost the same as the premium for ATC’s actives, i.e. about £3K. Has anyone ever actually done this? It’s certainly not what I did: the passive set-up I used was with a Devialet 200, i.e. £6K’s worth of ampage, though of course the Devialet is an integrated plus DAC, so not really comparable. As I say, it’s complicated.

Anyway I ended up buying some second-hand active ATC SCM50s, which I’m very happy with. They do classical music of all genres beautifully, mainly because of the amazing mid-range driver. Having said that, I have another (PASSIVE) system that’s in some respects better: Martin Logans driven by a Sanders power amp.

Conclusion: too many effing variables.
 
david ellwood said:
Proper feedforward requires two output stages and then a way of summing them. Not normally done at audio frequencies.
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True, but was claimed by at least one Japanese audio manufacturer (Sansui) back in the eighties.

I seem to recall that Wireless World* did some articles on the subject.

* I think it was WW - a bit too highbrow for Practically Electronics :)
 
davidsrsb said:
There are serious limits of how much feedback you can use in motional feedback. Feed forward offers improvement without the transient problems.
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Examples?

davidsrsb said:
As we are so used to bass doubling, a linear speaker is going to sound thin
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My speakers have flat response to below audiblity, with no bass doubling. They don't sound thin.
Which speakers have you heard that fit your description that sound thin?
 
Feed forward in this case means a compensating pre-distortion to a single output amplifier. This is a technique common in RF amplifiers. I have never met it in commercial use in speakers, but with modern DSP, it is simple to do and it works.
Every speaker I have ever seen measured has alarming distortion level in deep bass, 10% is common. Only using large bass drivers reduces but not eliminates this.
http://www.linkwitzlab.com/thor-measmt.htm shows some tests
 
AH. I see what you mean now. The compensating pre-distortion is very difficult to do in practice. Just trying to model the effect of a rubber surround is actually very difficult in practice. It's very non linear and temperature dependant.

It would be interesting to see the distortion at lf that SAM'ed speakers or KII 3s produce.

My speakers have measureably low distortion at lf. The problem I have, after using these for several years, is that most speakers sound rather unsatisfactory to me now - even if they have exceptional mids and treble.
 
S-Man said:
Just trying to model the effect of a rubber surround is actually very difficult in practice. It's very non linear and temperature dependant.
Click to expand...
Which is why about a factor of ten improvement is about the limit. It would be possible to calibrate the pre-distortion by measurement
 
lindsayt said:
Jonboi, I've heard a number of all in one active systems and NONE of them have sounded good enough for the price for me to want to buy them. And by good enough I mean "hearing what was on the recording as faithfully and authentically as possible".

IE the problem is not with me, it's with the all in one active speakers I've heard.

The general level and experience of hi-fi equipment on this forum is high. My speculation is that the reason that there are so many users of passive speakers here on this forum is that the active speakers they've come across have not been good enough for the price for them to want to buy them.

My speculation is that it really is as simple as that. And that in most cases passive ownership has nothing to do with a desire to tinker or to cling to old technologies, or some sort of rose-tinted nostalgic look at the past.
Click to expand...

Well, quite possibly.

Certainly speakers are a bit like marmite - some love them and others hate them.

For example SBL's aren't exactly awash with praise on these forums, and yet in conjunction with my then new Naim electronic, I literally tried every speaker the Naim dealer at the time had in stock, before settling on the SBL's as the best match for the Naim kit.

Some people here love Linn Isobariks. I knew someone that declared upon hearing them, that he'd put an axe through them, so disliked was the sound.

So there is certainly a great deal of subjectivity re like/dislike when it comes to speakers, active or not. And as a predominately classical music listener, what I listen for and find important musically, is likely to be quite different to many.

As regards active speakers, I'd speculate that the biggest hurdle is actually one of initial upfront cost.

One is effectively buying a fully finished and matched set of amplification and speakers at the same time - which in a high performance model is not exactly going to be cheap - you don't have the luxury of building it piece by piece, a bit at a time as the budget allows.

And of course, should you have the urge to 'upgrade' you have to effectively toss it all out and start again.

So the main drawbacks to active I'd say would be initial up front cost, expensive to upgrade, and inability to mix and match speakers/amps etc. (assuming a fully active speaker with onboard amps).

But, having been a passive speaker, separates system owner myself for nigh on 40 years, and having only gone fully active over the last 5 years, I would not personally choose to go back to separates on performance and overall ownership satisfaction grounds.

Cheers :)
 
mattgbell said:
I’m not entirely persuaded that active is better than passive all other things being equal.

I base my view on experience of the ATC SCM40s, which I’ve tried in both active and passive form. TBH I don’t think I’d be able to tell the difference between the two set-ups I tried. But it’s complicated because the 'all other things being equal' clause can be tricky.

To do the comparison on a level playing field, I guess you’d have to power the passive set up with power amps that cost the same as the premium for ATC’s actives, i.e. about £3K. Has anyone ever actually done this? It’s certainly not what I did: the passive set-up I used was with a Devialet 200, i.e. £6K’s worth of ampage, though of course the Devialet is an integrated plus DAC, so not really comparable. As I say, it’s complicated.

Anyway I ended up buying some second-hand active ATC SCM50s, which I’m very happy with. They do classical music of all genres beautifully, mainly because of the amazing mid-range driver. Having said that, I have another (PASSIVE) system that’s in some respects better: Martin Logans driven by a Sanders power amp.

Conclusion: too many effing variables.
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Yes, variables always add that 'It all depends' clause.. :)

However, ATC do state on their website the engineering and performance advantages of fully active speakers, where identical speaker models are compared active and passive. One assumes that the science is well researched and the argument proven.

I'm not able to make comparisons active v's passive with my Beolabs - Beolabs are all active across the board re their model range.

I do think once the initial price hurdle is crossed, the value is quite exceptional.

Consider the JBL Everests I heard about 12 months ago now - driven by some large Valve amps and the requisite wrist thick speaker cables - the Everests alone a 'bargain' at A$125,000. Or the B&W 800D's circa A$44,000 a pair, plus a pair of obligatory Classe mono blocks circa $A16,000 each, for an amp/speaker combination price of A$76k.

At those sort of asking prices (and you still have to factor in the wrist thick speaker cables, at $xxx per metre; the racks to hold the amps and so on - and the Beolab 90 is a relative bargain for a fully finished system needing only a source at A$110,000.00

At the recent Hifi show here where I heard them, they were using a router, NAS, and an Oppo 105d plonked down on the carpet for CD replay - no fancy racks or cables whatsoever.

Yet they comfortably outperformed everything else I and an electrostatic owning friend heard at the show, combining the transparency and neutrality of the big B&W's, with the amazing dynamics of the JBL Everests. That they are able to do it so easily and simply, and at the price was very much the eye opener at a show full of megabuck esoterica.

Cheers
 
Rodney gold said:
The only alternative I would have considered as against the spirits was a set of Avant garde Trios and 6 basshorns .. however that was at a cost of Eu 140 000.. and I didnt like the Trios "shoutiness"
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Its not the Trios that are at fault here. Trios, in fact all Avantgarde speakers need to be paired very carefully with "sympathetic" amplification and cabling. Pretty much like all horn designs do to achieve a high level of audio performance.
 
FWIW I find the active/passive argument pretty daft. There are good speakers, there are bad speakers, there are speakers that work to your taste in your room, there are speakers that do not. These are all far higher level concerns than how the crossovers work! It also needs to be pointed out that when people are discussing "active" speakers they are almost always only thinking of a couple of round moving coil drivers in a box. Many of the world's best speakers are not of this format (e.g. panels, horns etc)!
 
I think a lot of people have swallowed the marketing spiel on active speakers.
And a certain amount of possetting is occuring.
 
The whole point of 'contemporary' actives, is that their boundary filters allow them to be placed anywhere, adjusting to your taste, one speaker can be in free space and one tight into a corner and each individually adjusted, the Kii's also have 'contour' filters for fine adjustment , compact, completely full range and their 'controlled directivity ' means you hear more direct sound and less reflected, a complete system is just the speakers and remote.
Keith
 
I agree totally Tony. The crossover, whether it's active or passive is one of the least important parts of a hi-fi system in determining the overall sound quality. I'd rate it as about equally important as the digital source and less important than the support and location on which a turntable is placed.


You also make a very good point about the genre of speakers that are all in one actives. The best sounding systems that I've heard have been huge sealed boxes, large to huge high efficiency speakers and electrostatics. With each having different strengths and compromises. I've not heard all in one active speakers from any of those 3 genres. I have heard systems where the active crossovers and amplification have been outside the speaker cabinet and some of them have sounded fine.


This statement from Jonboi makes no sense to me "I do think once the initial price hurdle is crossed, the value is quite exceptional."

It's the initial price hurdle that makes the value unexceptional!


And the trick is to find speakers that sound at least as good as brand new JBL Everests for a lot less money. Something that is easy enough to do with Google and ebay.

Likewise, finding amplifiers that sound better than brand new Classe monoblocks for a lot less money is easy enough.

And as for wrist thick speaker cables? Not required in a World Class system, as speaker cables are even less important than the type of crossover.
 
I guess contemporary actives are OK if you want to colour and tailor music to your taste, but if you just want to hear what's on the disc, as the artist intended, buy ginormous passives.

Joe
 
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