Fatmarley
"It appears my intelligence circuits have melted"
Yes, ATC active vs passive are supposed to sound different, but I've heard by a respected speaker designer that active and passive can be made to sound identical.
Puzzling results with ATC SCM50ASLT loudspeakers vs. previous system
- Thread starter Matthew J
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S-Man
StrivingON
That implies that at least one of them is wrong!
evand
Just press play
Nope, with actives bass, midrange and tweeter are independently amplified and seeing as the amplification was specifically designed with the drivers in mind you have a great match also. Contrast that with a passive that’s driven by whatever the user decides to put in front of it. Love the conviction though.
Don’t forget that you’re speaking about actives. For the 6k difference there’re amps with a design philosophies non-achievable for rather simplistic ATC amp-packs (though there’s always a debate about active vs passive crossovers, I know).
S-Man
StrivingON
So please tell us what is special about ATC amps.
I think I know about the relative capabilities of the two systems I ran. Amp packs don’t require casework & are designed to drive a specific load. That is rather different from simplistic. They actually operate with more class a bias, very capable they are too.
Active beats passive all day long.
cooky1257
pfm Member
FWIW, when porting these enclosures ATC tune their cabinets very low- in the case of the 50/100/150 it's around 20 hz, this gives a critically damped system Q of about 0.5, which is more like a sealed box, the port is there to limit ELF excursion and distortion not to supplement bass output. The enclosures are lined with the usual acoustic foam but also filled will long fibre wool. They do not behave like a conventional bass reflex.
i don't think I've ever heard them described as magic speakers, their reputation has been well earned over 50 years in both the professional arena such as recording and mastering studios and the domestic market- that's a long time in the game, you don't have to like them but the reputation suggests many do.
www.miraval-studios.com
i don't think I've ever heard them described as magic speakers, their reputation has been well earned over 50 years in both the professional arena such as recording and mastering studios and the domestic market- that's a long time in the game, you don't have to like them but the reputation suggests many do.
Miraval Studios | More than a recording studio in France
Miraval Studios, the iconic recording studio is back. Founded and re-designed by Brad Pitt and Damien Quintard.
www.miraval-studios.com
He just has. They are designed for a specific purpose. Stand alone amps don’t have that luxury.
Did this respected designer have active & passive versions of said speaker?
Fatmarley
"It appears my intelligence circuits have melted"
https://www.diyaudio.com/community/...icency-loudspeakers-horn-onken.139921/page-12 - Read Gedlee from post #224 and on.
So just some DIY guy? I just can’t begin to be bothered.
In the ATC world passive 3-ways are crazy difficult to drive, however I guess Audio Note, DNM, Lavardin etc. would disagree, and for a reason.
Wrong again. They are not very sensitive but have a pretty stable load. You could argue that they are just more honest with their specs. There are far more difficult speakers out there.
Fatmarley
"It appears my intelligence circuits have melted"
Nope.
ATC are respected speaker designers, at least in some quarters, and they say the advantages of active over passive drive are:
“While it is possible to design a high performance loudspeaker using passive components, an active design has a number of benefits, these are listed below;
1) More accurate crossovers
As the separate amplifiers in an active system are located after the crossover, they only operate over a limited bandwidth. This reduces intermodulation-distortion and, in comparison to a passive system, even a bi or tri-amped passive system, an active system will show 15 – 20dB lower intermodulation distortion.
3) Improved Frequency Response and Stereo Matching
An active system can very simply feature individual gain trims for the two, three or four amplifiers involved. This allows very simple fine tuning of the frequency response and the stereo matching. Similar matching in a passive system would involve the replacement of large, soldered passive components which, in practice, is difficult and time consuming for the manufacturer.
4) Lower Cost for Higher Performance
Because an active system is designed, engineered and implemented by a single manufacturer into as compact a package as the design allows, cost is saved on electronics case work and packaging and the manufacturer can invest in real performance enhancing changes or pass the saving on to the customer.”
It may of course be that ATC know nothing, and the o/p will be able to take his decades old speakers, knock up an external point-to-point crossover, sprinkle on some DSP fairy dust and end up with speakers “indistinguishable from the ATC system” (his very words). And then again …
“While it is possible to design a high performance loudspeaker using passive components, an active design has a number of benefits, these are listed below;
1) More accurate crossovers
- Active filters allow independent control of level and phase(time). This is not possible with passive crossovers. With a passive crossover any changes you make to the circuit affect both level and phase. The benefit this allows is that we can adjust for the crossover to have a perfect magnitude response and phase response. The result is that the stereo imaging is much more stable and the tonal balance of instruments is improved.
- An active filters performance is not changed by the temperature of the drive unit voice coil as they are not directly connected to them. A passive crossovers performance (filter shape and crossover frequency) will change with voice coil temperature which, increases with SPL (input power). This leads to passive loudspeaker systems having a slightly different sound when driven at low SPL compared to high SPL. The performance of active ATC systems changes very little with drive level.
- More efficient crossovers. Active crossovers do not need to use series inductors to achieve their filter shapes. Series inductors have resistance that reduces bass driver efficiency and also increases the Q of the low frequency tuning.
- More cost effective crossovers. Passive crossover networks use large, bulky and expensive components in order to deal with the high voltages from a power amplifier. Active crossovers offer better performance for lower cost.
As the separate amplifiers in an active system are located after the crossover, they only operate over a limited bandwidth. This reduces intermodulation-distortion and, in comparison to a passive system, even a bi or tri-amped passive system, an active system will show 15 – 20dB lower intermodulation distortion.
3) Improved Frequency Response and Stereo Matching
An active system can very simply feature individual gain trims for the two, three or four amplifiers involved. This allows very simple fine tuning of the frequency response and the stereo matching. Similar matching in a passive system would involve the replacement of large, soldered passive components which, in practice, is difficult and time consuming for the manufacturer.
4) Lower Cost for Higher Performance
Because an active system is designed, engineered and implemented by a single manufacturer into as compact a package as the design allows, cost is saved on electronics case work and packaging and the manufacturer can invest in real performance enhancing changes or pass the saving on to the customer.”
It may of course be that ATC know nothing, and the o/p will be able to take his decades old speakers, knock up an external point-to-point crossover, sprinkle on some DSP fairy dust and end up with speakers “indistinguishable from the ATC system” (his very words). And then again …
Why to use 350w per channel as native solution therefore?
cooky1257
pfm Member
To be fair we don't know the complexity of the passive network or the extent the drivers we're well behaved over their chosen bandwidth that Geddes was talking about, If it was simple then it's a no brainer. I'd heard that the Passive/ active ATCs sound pretty close.... When very good amps are used.
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Pretty obvious really, the drivers are capable of going very loud, most domestic listeners will never go near their outer limits. This is part of the pro heritage.
Mine only have 272 watts available.
Nobody never actually listens to more than 5-10w in terms of loudness, single-ended amp will not be a touch quieter
S-Man
StrivingON
No he hasn’t. Neither have you.
What’s special about them?
(What’s actually highly amusing here is that they do use a different topology to almost everybody else with their grounded source output stage. But that just demonstrates that you haven’t got a clue what you’re talking about).