Is it time for active speakers?
- Thread starter kc5819w
- Start date
Rodney gold
Im just me...
Emporiumhifi , Its NOT that easy to convert a passive to full DSP active.. all the ingredients are nothing , its the measuring the speaker and tweaking the xover and voicing the speaker that is not trivial
Purité Audio
Trade: Purite Audio
If you do decide to 'activate' a pair of passive loudspeakers start with the existing passive crossover parameters, MiniDSP make some excellent and in expensive processors and software.
Keith
Keith
S-Man
StrivingON
S Man.
You've been reading too many comics
How could you know what you've never had?
The inventor of the ZRB (zero resonance bass) system told me that he recently had a highly regarded speaker designer round for an evening of listening. At the end of the evening the designer, who is a proponent of big speakers (his own use 2 X 15" per side), pronounced the system "does not sound real".
This critism is valid as my pal is using a rather poor Behringer analogue XO, which does add some artefacts that would make the reproduction sound "electronic".
Anyway, the point of the story is that a week later the speaker designer called back to say his own speakers don't sound right in the bass!
Once you get used to low distortion bass with accurate transient response it is very difficult to go back!
Purité Audio
Trade: Purite Audio
When is the ZRB going to become available commercially, I would be interested to hear it again.
Keith
Keith
Purité Audio
Trade: Purite Audio
Yes I am always interested in innovation, the Kii's controlled directivity only operates down to around 80Hz, even the Beolabs only to 60Hz ( I believe) so low bass standing waves can still be an issue, although here they do appear significantly reduced compared to my other full-range loudspeakers.
Keith
Keith
merlin
Avatar changed - Town names deemed offensive.
I was guilty of working with Peter Lyngdorf at shows maybe a decade or more ago now and owning a few 2.2 systems S Man.
I don't miss it. The truth is that 90% of the music I listen to is amplified anyway, being either vintage rock or electronica. It's usually monitored and mixed using traditional equipment and a Fender bass sound comprises the instrument and the amp/speaker.
RCS and other digital wizardry can produce remarkable results in some cases and with specific recordings IME. Give me the best monitors whose parameters are suited to the listening room however, and enough watts to drive them effortlessly any day I'm afraid.
It sounds more realistic.
I understand where you are coming from however. I was a DSP and DRC evangelist back in the day. It was visiting Joel in Japan that realigned my compass.
I don't miss it. The truth is that 90% of the music I listen to is amplified anyway, being either vintage rock or electronica. It's usually monitored and mixed using traditional equipment and a Fender bass sound comprises the instrument and the amp/speaker.
RCS and other digital wizardry can produce remarkable results in some cases and with specific recordings IME. Give me the best monitors whose parameters are suited to the listening room however, and enough watts to drive them effortlessly any day I'm afraid.
It sounds more realistic.
I understand where you are coming from however. I was a DSP and DRC evangelist back in the day. It was visiting Joel in Japan that realigned my compass.
Tony L
Administrator
If this highly expensive digital fanciness exists above 60Hz it is of limited use for correcting bass booms etc as they tend to reside below that, e.g. the node in my room that smallish ported stand-mount speakers often find is at 48Hz. Thankfully big speakers seem to miss it entirely and just have a slight lift with no boom! Is the acoustical/mechanical directivity of the MEG RL901 (one of the few active speakers that really interests me) any more successful?
Emporiumhifi
Well-Known Member
we will have to agree to disagree, an experienced hifi er should have no insurmountable problems.
Emporiumhifi
Well-Known Member
Good advice, I recommend starting with the same xover points but using 4th order roll off (preferably Linkwitz/Riley) then can play with the xover frequencies a little, Even the humble Behringer xover sounds better than passive speaker xovers.
Emporiumhifi
Well-Known Member
and another thought, everyone keeps talking about digital signal processing for an active system, while this certainly is a potentially useful tool it is not essential for a considerable improvement in sound quality using an active system, I have set up active systems several times for demo purposes using an old Sony Esprit 4 band analogue xover (as well as others such as Behringer old and new) and just used whatever amps were to hand, used a sweep from a signal generator to match levels and it's 90% there with just that.
Emporiumhifi
Well-Known Member
what is ZRB? is this another version of motional feedback?
DNM
pfm Member
I use DSP crossovers between active subs and passive speakers and it took a lot of trial and error to achieve a seamless inaudible transition between drivers with a presentation that I liked.
Simple FR measurements will only show you if you have a smooth FR at the Xover, which is pretty easy to accomplish over a fairly wide band, however you may also require biquad filters in the Xover design to get the desired FR, something that would have already been accomplished in the voicing of the passive design. If you don't know the drivers F and Q, you're going to have to measure the individual drivers to figure it out before calculating the filter.
The desired FR doesn't of course tell you the differences in timbral presentation between drivers and it took me many listening hours to find the Xover sweet spot. It was of course much quicker and easier adjusting a DSP and listening in real-time to the results compared to the painstaking work involved adjusting a passive Xover network. To the uninitiated however, its by no means as trivial as you seem to be making out.
Emporiumhifi
Well-Known Member
I would like to answer his sweeping statement! whilst I don't neccessarily advocate buying active speakers as this limits one's choices, converting standard speakers to use in an active system has some serious advantages, firstly speaker damping is much improved, take a hypothetical 10 ohm speaker connected to an amp with a hypothetical dc output resistance of 0.1 ohm, this gives a speaker damping factor of 100:1, now put inbetween the xover components and add say 0.5 ohms for the inductors and extra soldered joints etc. the speaker now sees 0.6 ohms and the damping factor has dropped to less than 20:1, it doesn't matter if the amp's quoted damping factor was 1000:1 the actual damping factor will be less than 20:1 so first improvement will be tighter bass and cleaner mid. Another benefit is the bass amp can now push bass current to near clipping as no headroom is required to run the mid and the mid can likewise be run to near clipping etc, power required above 300hz is appx same as power required below 300hz amps one can now use amps of a quarter of the power of the single amp, on top of which no power is wasted in the xover. another benefit is tha 4th order xovers can be used which is the only one after 1st order which is phase coherent so transients will sound punchier/more coherent. one can choose/opitmise amps and cable for the bandwidth they are working in too.
Purité Audio
Trade: Purite Audio
I believe that is classed as a 'powered' loudspeaker rather than active.
Keith
Keith
Suffolk Tony
Aim low, achieve your goals, avoid disappointment.
Using different amps on DBL drivers really doesn't work too well in my experience. Like all traditional Naim speakers, DBLs were designed primarily to be actively driven and sound much better that way.
yuckyamson
pfm Member
If it's not custom built amp packs by the manufacturer (ala ATC), I've never felt it worked better to use different amps on different drivers. Synergy counts. Amps should always be matched, IMO.
(as per Tony above here).
With Linn's active systems in early days we did occassionally mix up the amps, but in those cases we always put the best amp on the treble. Even then, I'm not sure it was a good idea and sounded that much better.