I Was Considering Active, Then I Watched This ...

Damning truth for me is that I have been going to trade shows for 30 years and have never heard anything particularly good as the rooms are awful and totally mask speakers. If you are using shows as reference I don’t know what to say.

Active speakers will be for people who want accurate reproduction. Passive speakers will be for people who think what they like is accurate.

It is impossible to achieve in a passive speaker what is possible in an active speaker. It is a simple truth.

douglas_schroeder2,742 posts12-10-2020 9:12pmOne damning truth for me is that in 15 years of shows I don’t recall any active speaker (Legacy audio being the exception; hybrid) making my top 3 of show, ever. Until they actually DO outperform they are for me a waste of my time.

An active speaker can:

- correct for unit to unit driver variation better than the best manufacturing


- tune the crossover perfectly in frequency and time for the exact drivers in every unit produced


- correct for phase across the whole frequency spectrum

- use current feedback from the driver to implement distortion reducing drive

- use position feedback to reduce distortion

- use feed forward control methodologies to reduce distortion


... As a start


External amps will never be able to accomplish what internal amps will be capable of if accurate sound reproduction is your goal.

Deep understanding of the drivers and how to correct for their faults and understanding what is a factor of driver and cabinet and correcting for same.

invalid75 posts12-11-2020 8:45pmI don't understand why you need a speaker manufacturer to build an active speaker, when you can make a lot of speakers active with an active crossover and your choice of amps.

No one talks about ABx for speakers because the sonic character is generally enough to easily match x to A or B. Of course AB speaker comparison is very difficult due to movement and positioning issues and accurate volume matching in room without suitable tools or experience. It's almost silly bringing up.

Also silly is to use Legacy as an example, not the most accurate speakers at the best of time and no guarantee that the passive or the active versions are optimum and doubtful Legacy had the knowledge or experience to optimize an active crossover or if DSP, the ADC to be transparent.

The best would be to compare equal priced speakers considered state of the art in both genres and then compare the sound to very neutral headphones as the goal is not to determine what you "like" but what is most accurate. We are not judging flavor here but accuracy.

Unfortunately phusis, your view towards active speakers is simple, just the replacement of passive crossover to active crossover. There is far more possible in terms of active speaker development that cannot be implemented in this piece-wise fashion.  Not to mention very few have the tools, knowledge, or space to develop their own crossovers effectively. It is not something that can be done by ear, and done well, requires either a large space for effective gated measurement and/or an anechoic chamber. The goal is not "okay" it is great.

phusis,

Why are you going on about something that 99.9% of audiophiles have no interest in doing, and 9/10 of the remaining 0.1% are going to screw up?

I am very cognizant of the DIY speaker community. There is some great craftsmanship, and some very good mid-level speakers, but at the top end, I can't say I have heard much.

That you keep repeating "Digital Cross-over" like it is the be all and end all shows how large the gap is between the average DIYer / probably most DIYers and truly professional designers working on advanced active speakers. It is not simply a matter of getting some amps, even expensive ones, and a DSP and playing with digital crossover implementations, and no, I don't care how long you listen to it, you will never achieve a very good design without complementing that with a lot of measurements, and again, most DIYers have fairly basic measurement capability for advanced speaker design. I know ... pretty much the same techniques, but better S/W than what I was using to DIY 20+ years ago.

The implementation of a design I was involved in required a custom amplifier topology that you cannot buy off the shelf. The techniques implemented go beyond simple digital cross-over design and are beyond almost all DIYers as it would be rare to find that cross disciplinary expertise. That is not even getting into things like finite element analysis to optimize bracing or complex acoustic field simulation to optimize the lenses.  The drivers were not off the shelf, but optimized for our drive/control methodology. Again, not available to the DIY community.

Don't get me wrong, there are some great DIY designs out there, but as you move into active designs, the complexity of what is possible just went well beyond "DIY". Its a lot more than just a digital crossover and amps (and drivers, and box, and ...)

Phusis I will just leave this here as it shows to those who know something about actual loudspeaker drivers that you hit your knowledge limit quite early. You just don't get it and I don't think you have the knowledge to get it. There are things we have known since the 70s about loudspeaker driving that clearly you don't. Good day. Love to have a discussion with you but you don't seem interested in learning but may want to learn about more complex drive methods for loudspeakers all beyond your simple implementation.

As an outset IT IS about simply getting that quality digital XO hooked up and extra amps and cables all connected,

Getting rid of the cross-over on the power side of an amplifier and instead letting the amps see their respective drivers directly is in itself of significant importance, both in regard to letting the amps work at their fuller potential (effectively minimizing the need for amp prowess here)

I think this nailed my feelings on the subject.

Active speakers and DSP can nail frequency response. Ruler flat.

But just based on being active and using DSP, does not address the type of subtleties that speakers and various amp combos are capable of.

And this is why they are feeling and not reality or informed opinion.

When you talk about rudimentary things like crossovers, then you are already 5 years behind, and certainly not looking to the future.

"There are no drivers made, that do not have 'problem' frequencies within their passband, that need to be compensated for.

And passive speakers will never be able to compensate for this. Active will.

teo_audio1,702 posts01-13-2021 11:13am"Good enough" (a plateau by any measure): active

Inveterate tweaker looking for the best (’peak audio’): passive

It’s a really simple equation, in the end (with all the data points on the analysis table).

Good Enough: Passive
Capable of performance no passive speaker will ever be able to achieve due to the inability in a passive speaker to have immediate feedback from the driver itself, nor intimate knowledge of said driver and any number of other factors:  Active


Active speakers are quite threatening both to the speaker community and the amplifier community. Similar to good Class-D with amplifiers, very few speaker companies will have the technical wherewithal to extract the maximum performance out of active speakers and we are just getting started. There are things that can be done in an active system that are virtually impossible in a passive system. Not just simple things like perfect phase alignment even with higher order crossovers,   but applying closed loop position feedback to higher and higher frequencies, compensating for thermal and magnetic compression (and other magnetic factors) on all drivers, and even some concepts for reducing the impacts of doppler distortion.  Add in multiple similar drivers and you start to get into controlled dispersion, etc.

If you apply old thinking to new ideas, you end up with obsolete opinions.

This absolutely blows my mind that someone would think pros [specifically recording engineers] don’t understand the details or are ignorant of the very details that audiophiles value. They are obsessed with it!

Meh, you should see the scorn they heap on electrical engineers :-)