Daft Question Time - Active Speakers/System

This might sound completely daft but how does an active system work, I have read about them but I have no idea about how they are set up.

What kit is needed to do a basic active system?

Can I use something along the lines of Naim’s NSC 222 and then just a set of speakers ATC’s SCM19A for example?

Some basic guidance would be gratefully received.

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Here you go;

An external crossover is used bypassing the speakers internal crossover, meaning each speaker driver is now independent.

The pre -amp goes to the external crossover which splits the signal to two power amps, then each amp powers one speaker driver

Job done.

DG…

Yes, the ATC 19a has an inbuilt amplifier.

I have a 222 and Adam A7V active speakers ( they’re a temporary measure ), the XLR outputs from the 222 connect to the active speakers.

You just need to switch the speakers on with the 222 and bob’s your uncle.

If you google YouTube 13th note hifi you’ll see a review of the speakers.

My previous post and DiggyGun’s both answered with regards to passive vs active crossover speaker configuration.

These ATC speakers are a combination of speaker and amplifier. So you feed them with a preamp. The power amplifier is in the speaker.

This is also called active but perhaps misleading; studio monitor is another term. I suppose “active” in both situations just means “something is powered”.

So:
“Going active” is the phrase when someone wants to convert their passive speakers to active. Some eg kudos make that very easy for you. Others need modifications ref the crossover. This is all about having an active crossover. In Naim speak this is the snaxo and there are various models. Snaxos need a hicap or supercap and you end up with lots of boxes and lots of speaker cables.

Active speakers like the atc, Adam etc quite a few of them being synonymous with recording studios are the “amp inside the speaker” version of active. So not about powered crossovers.

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There are two forms of active speakers.
One where the amplification is in the speakers, ATC actives are an example of this.
The other is where the preamp out goes into an active crossover into power amps and then directly to each drive unit in the speaker. Kudos I believe go this way. In years past Linn and Naim used to work together for active versions of the Kan, Sara and Isobaric speakers.

Though to be strictly accurate there is a sort of third version, powered subs are active so you can have a passive-active hybrid set-up. There are a small number of speaker manufacturers that do this with their speakers and of course, you can do this by adding a sub to your passive speakers.

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I’ll let others with more knowledge than me comment.

My simple take is that when you have a system with 2 or more speakers per speaker unit (channel - left or right if talking stereo) then the sound needs to be split between low frequencies and higher frequencies. Typically this crossover may occur at around 2.5 to 3 kHz. If this crossover occurs after amplification then the components are typically larger and more difficult to manufacture accurately than if the filtering occurs before. Hence some would say filtering before amplification is better. The downside of this is that the number of stereo amplifiers required will increase from one for a post amp filter to 2 x stereo amplifiers if there are two speakers per channel speaker unit. This in itself may cause a loss of the benefit of filtering prior to amplification.

My understanding is that the ATC SCM19A has the required active filter prewired before the amps (one per speaker within the speaker unit) all inbuilt into the speaker so yes you could connect them direct using the appropriate XLR cables. Note you would also require a mains lead for each speaker to provide power for the inbuilt amps/filter.

Happy to be told I’m wrong.

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With active, and electronic crossover is used. It splits the output of the preamp into frequency bands, which then go to separate power amps. The power amps then connect direct to the speaker drive units.

The advantage is that the frequency splitting is done at low level, rather than the high (speaker) level that happens in a standard passive speaker.

The Naim way is to send the signal from the preamp to an electronic crossover, then to a number of power amps and then to the speakers. With ATC, the crossover and multiple power amps are built in to the speakers.

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This is exactly what I want to avoid.

If I have this right (and I probably haven’t), a simple cable from the pre-amp to a set of speakers with amplification built in would be the preferred option.

For example; Looking at the back of the NSC 222 there are XLR output connections which can go to a corresponding connection on the back of the ATC’s, I presume that if I made this connection I would have an active system in its simplest form?

I am unsure if the NSC 222 is my choice of pre-amp or if the ATC’s would be my choice of speakers but in principal this would work?

Thanks.

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I think you are of the correct understanding for the NSC222 ATCSCM19A scenario. Obviously only you can decide of the sound is what you are looking for. As ever a demo in dealer location to confirm initially prior to demo in your home is a good route to follow.

Not sure what dealer you are using but IIRC there is one outside Oxford who stocks all the components you are looking at. Naim, Linn, Kudos, ATC plus others. He is also very happy to help where he can: just my opinion.

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The Oxford / Reading corridor used to be my stomping ground, but that was many years ago, I am a few hundred miles from the area nowadays but my local dealer does stock all the brands you mention.

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That’s exactly how it would work.

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Thanks, that is a great help.

Now I just need to find other speakers that have the same connectivity.

I wouldn’t get too hung up on active speakers. The ATC 19 for example is very large, the same size as the 40. Don’t rule out a 222/250 and passive speakers. Just find the sound you like and then work out how best to achieve it.

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I won’t forget sound, I am just trying to keep the box count down, I don’t want the number of boxes to get excessive, hence my thread on one box options. The idea of having a pre-amp going direct to speakers is appealing - but only if the sound works for me.

At the moment a passive setup of a 222/250 combo is in pole position although I am not sure of speakers as yet.

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Do you have any auditions arranged yet?

I have a session set for the end of the month, I’m not rushing into the changes, going to ask lots of questions and do as much listening as possible before making any decisions.

Fair enough but with active speakers like the ATCs, you will still need to plug both of them in to mains and you still need cables from the pre amp to speakers. A 2 box streamer plus amp may be cleaner in terms of cabling…

This is a good picture from Kudos showing an active set up with a Linn Selekt DSM and Titan 606 loudspeakers.

Simple setup;
One box
One mains cable
One Ethernet cable
Two loudspeakers
Two runs of loudspeaker cables
No more

DG…

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Indeed most commercial active speaker / systems are where typically balanced feeds from the pre amp outputs connect to the active speaker, where the signal is split via typically an active crossover built into the speaker’s electronics and then fed into a separate power amp per driver… using very short leads between driver and power amp, which is often advantageous.
This is also typically advantageous for high power and/or where subtle eq per speaker is required.
With passive speakers most use a passive crossover, where here the simpler the crossover with as few reactive components in the signal path often the better the performance.