ARCAM AVR 600 with ATC

[admin_exported]

I am considering the Arcam AVR 600 with ATC SCM 40 fronts, ATC 11's rear and ATC C3 Center with a C1 sub.

I have been told that the ATC's wont respond well at low listening levels say -25db

Also told that ATC's are hard to drive.

Any advice on this combo ?

 

[MUSICRAFT]

Jimhansi:

I am considering the Arcam AVR 600 with ATC SCM 40 fronts, ATC 11's rear and ATC C3 Center with a C1 sub.

I have been told that the ATC's wont respond well at low listening levels say -25db

Also told that ATC's are hard to drive.

Any advice on this combo ?

Hi Jimhansi

Whilst the AVR600 would not be my first choice however it has still got enough power which is also more than sufficiently potent to power the ATC speakers.

The ATC's have excellent dynamics and therefore ime sound perfectly fine at low/moderate levels. This is something that many of my clients who have bought ATC speakers have also commented on after they have acclimatised to them.

The common belief that ATC's are hard to drive generally stems from their low sensitivity. Fortunately the ATC's drive units are very constant thereby allowing the amplifier to deliver it's full power all the time (prior to clipping). Some very efficient speakers have an impedence that can drop down to low levels such as 2ohms. At this level many amplifiers will struggle to provide sufficient power or will give no power at all. The impedence of a speaker is far more important than the efficiency.

The ATC's with their (amongst other qualities) clear, natural , uncoloured and powerful presentation will allow the qualities of the Arcam to shine through by enabling it to breathe.

Thanks

Rick @ Musicraft

 

[Frank Harvey]

Hi Jim

Whether the ATC's respond well at lower volumes will depend on the amplifier's current capabilities. If the amplifier lacks current, they'll need to be turned up a bit before they 'get going', and sound a little soft. Amplifier's with plenty of current, and then some, will sound dynamic regardless of volume. Speakers are only 'capable' of being dynamic as they are a passive entity - it's the amplifier that provides the current and gives the speaker it's 'dynamism'. It's down to the amplifier to tell the speaker what to do, it's then down to the speaker being capable of doing it.

ATC's are generally harder to drive than most at their price points - they're similar to the Spendors in how far the volume control needs to be turned. Many speakers tend to be about 87-90dB on average - the ATC's are 84-85dB. 3dB is known as a doubling in volume.

As for their matching with the Arcam, no problems at all. Tonally, the ATC's are pretty neutral, and the Arcam is on the smoother side when compared to most, so it should be a fairly easy package to listen to for longer periods. If you're not going for a fill 7.1 system, I'd strongly recommend bi-amping the SCM40's to get the most from them with music in particularly.

A couple of years ago, we had a musical evening where we used an AVR600 to drive about £15k's worth of KEF Reference, all of which are 4ohms, instantly making them more demanding than the ATC's. The 205/2's and centre are both 90dB, the 201/2's are 86dB. It drove these almost non stop for the whole evening, running from about 5pm until almost 10pm when we finished. It didn't cut out, and displayed no signs of struggling in it's presentation. It's one of the most capable amplifiers under £6k.

You can rely on the Arcam to drive whatever you decide to buy, unless they're real awkward .

 

[Anonymous]

Thanks for this

I tried them with a Denon 4810. For stereo , imo, Arcam by a fair margin.

Happy to have a recommendation for another combo. If I go to an amp , to preserve ease of use, wont I need one with a HT bypass?

 

[Anonymous]

I have got the essence of what you are saying- thank you. For the benefit of those less knowledgable, can you expand on the 87 db v 84 db bit?

 

[MUSICRAFT]

Jimhansi:

Thanks for this

I tried them with a Denon 4810. For stereo , imo, Arcam by a fair margin.

Happy to have a recommendation for another combo. If I go to an amp , to preserve ease of use, wont I need one with a HT bypass?

Hi Jimhansi

Another amp that you could also consider is Yamaha's DSP-Z11 (particularly now that the they are generally now available for not too much more than the RRP of the AVR600). I have extensively used the DSP-Z11 with the various ATC speakers (including the models that you are considering) and it sounds superb.

Thanks

Rick @ Musicraft

 

[MUSICRAFT]

Jimhansi:

I have got the essence of what you are saying- thank you. For the benefit of those less knowledgable, can you expand on the 87 db v 84 db bit?

Hi Jimhansi

Generally a speaker that has less sensitivity than one at 87db will require more power to give a similar playback level. However it is not always quite as simple as that because other aspects such as an amplifiers overall power, current capability, damping factor (an important factor that is often overlooked) etc. will also play a part. Fortunately with the ATC speakers (as i said previously) the drive units are very constant thereby allowing the amplifier to deliver it's full power all the time (prior to clipping). Some very efficient speakers have an impedence that can drop down to 2ohms. At this level many amplifiers will struggle and will not provide sufficient power or will give no power at all.

The fact is that the impedence (resistance/load it presents to an amplifier) of a speaker is far more important than the overall efficiency.

Btw, the Arcam, Denon and Yamaha amplifiers that have been mentioned are more than capable of driving the ATC speakers.

Thanks

Rick @ Musicraft

 

[Frank Harvey]

Jimhansi: I have got the essence of what you are saying- thank you. For the benefit of those less knowledgable, can you expand on the 87 db v 84 db bit?

Speakers have a sensitivity rating. This gives you an idea of how efficient they are in changing the electrical signal into acoustic energy. With all other things being equal, an 87dB speaker is going to sound twice as loud as an 84dB one for any given volume being fed to it by the amplifier. This is basic physics, and can't be messed with.

The nominal impedance of most speakers tends to be 8ohms, but many designs drop down anywhere between 5ohms and 3ohms (sometimes lower) in the lower frequency regions of it's frequency range. A lower impedance draws more current from the amplifier, so for low impedance speakers, a high current amplifier is needed to be able to drive them properly. An amplier that's not up to the job will become unstable when trying to drive these lower frequencies, which can lead to damage of the amplifier and/or the speakers.

Damping Factor is the amplifiers ability to control a drive unit. This doesn't affect efficiency or how loud the speaker sounds, only the amplifier's ability to eliminate unwanted cone movement. Damping Factor is also highly variable, which, like impedance, depends on frequency, among many other things.

That's about as simple as I can explain them

 

[Anonymous]

That was certainly helpfull . PMC OBi's have been suggested as an alternative. Any pluses or minuses with this and either the Aracm or Yamaha?

 

[Anonymous]

Cool- I get it .. but how does one tell or measure an amplifiers damping factor? Is there some stat that the manufactuers quotes or some calc that one does?

 

[Frank Harvey]

Some manufacturers will give the damping factor in their specs, but not all. If it's not in the specs, you'd need to get in touch with the manufacturer. To be honest, this isn't a spec that has been widely used when choosing equipment, and doesn't really tell you what the amplifier is going to sound like. Manufacturers will quote damping factor as a single figure, but the figure varies depending on frequency, so I can only assume manufacturers show an average figure.

 

[Anonymous]

Understood ..how would the Arcam go with the PMC OB1i speakers.

Is this considered a "bright combination"

 

[JoelSim]

Jimhansi:
Understood ..how would the Arcam go with the PMC OB1i speakers.

Is this considered a "bright combination"

I wouldn't think so. Neither of these brands are considered bright. Ever.

 

[Frank Harvey]

The PMC's HF can be a little strident with the wrong amplifier, but not with the Arcam - it's an extremely good match.