Speaker Advice for 2.1 Amp

I am planning a garden audio system with 3 stereo pairs of speakers and a sub woofer to go with an Arylic AMP2.1. but I am concerned that it might not be powerful enough ( it is for background music primarily over 3 distinct areas of the garden.)

I would welcome any advice please

The speakers I am thinking of are:

3 x Pairs Polk Atrium 4
Specs per pair

  • Nominal Impedance 8 ohms
  • Recommended Amplifier Power 10 - 80 w/channel
  • Efficiency 89 dB

1 x Polk Atrium SUB 100
There are 2 voice coils

  • Efficiency - 88dB
  • Impedance - 8ohms (per voice coil)
  • Recommended Amplifier Power Per Channel 10 watts → 200 watts
  • Frequency response - 40-200Hz

Are you planning on running all six speakers off a single 2.1 amp? I would not recommend that as running three 8 ohm speakers in parallel will bring that down to a 2 ohm load on the amp and the stereo amp is rated at 4 ohms. You will run out of headroom and distort the speakers or possibly burn out the amp. The mono subwoofer channel will be fine for the sub. If it’s just background music for your patio a sub may be overkill especially if your mainly listening at low volumes. That atrium sub100 is insanely pricey for a passive subwoofer. If you do choose to go that route I highly recommend acp workbench so you can dial in that sub a bit and set crossover levels.

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Also FYI the Polk atrium 100 sub was designed to compliment the Sat300 model speakers. I’ve read users having performance issues using this sub with differing models.

Hi @Jzad ,

Thanks so much for your quick response. Yes I did wonder whether it might be too much. I agree about the Atrium Sub, but I can’t find any other outdoor sub that is as weather-proof - I do like my bass. :slight_smile:

Is there any better way of daisy chaining another amp to spread the load across a couple of amps (would they both need to be smart amps like the 2.1 or could I use a cheaper ‘dumb’ amp that could piggy back on the functionality of the 2.1

Ok. Thanks that is good to know I wasn’t aware of that.

@nickwild thinking aloud you talk about 3 distinct zones in the garden. Functionally do you want to be able to control volume, content etc. Zone by zone ? If so why not 3 amps. No experience with the polks but they seem expensive. I used to use rocks in garden but moving towards Herdio Marine IP66 speakers. Just FYI as these are totally different animals to I think what you are looking at. Not advice just some info :slightly_smiling_face:

This stared as a bit of a fun project but ultimately I was impressed with th £25 per pair speakers for outdoor use. IP66 Nobby Box

Are your speakers completely subjected to the weather elements or are they under any type of covered patio or location where they won’t be exposed to rain? I pieced together a 7.1 system on my patio, luckily it’s covered that slams. I know my neighbors hate me but it’s great for movies. I didn’t use Arylic products for that system but it was affordable if your willing to go with used gear. Seems kind of counter intuitive to use the 2.1 amp and then have long cable runs to outdoor speakers. If the amp would need to be housed inside or covered away from the actual speakers I would recommend a different product entirely. If you just like the wireless control and functionality of acrylics software I would recommend using the wifi stereo receiver pro or upstream mini connected to a more powerful multichannel amplifier and possibly some beefier speakers with better bass extension and forgo the subwoofer. I’ve yet to see an outdoor weather rated sub that hits lower than than some of the better designed 2 way boxes anyway. What would be important to know is coverage area. Are there separate zones that need to be covered or are you trying to cover a large space with a modest decibel level. Chances are you would need multiple subs as well if you want similar bass response across the entire coverage area if it is large.

Thanks @Jzad and @NWT.Stuff really helpful thanks for spending time to reply.

These are really 3 separate UNCOVERED areas that need coverage with one audio source rather than zones that need to have different audio feeds. For ease I am actually thinking of dropping this to two areas using only 4 speakers. I presume if I did this the amplifier would cope better?

We live on top of the Pennine Hills in the UK so we do get some pretty brutal weather - which was why I was considering the Polks as they had a good combination of audio quality and resilience.

@NWT.Stuff I did think about the Herdio speakers, but TBH they seemed to get bad reviews for longevity (i.e. rusting) BTW great Nobby Box project!

@Jzad I am happy to go with used gear and I would consider using the Arylic receiver with another amps and speakers. The maximum speakers distance from the amp is about 7m ( I am planning to put the amp in a waterproof wall mounted box).

Area 1 is an outside dining table (with the mounting point for the speakers about 3 m away from the table)

Area2 is the hot tub/ decking area ( this was going to be 2 areas originally). The Hot tub and decking area is about (7m x 7m). I was going to put the sub in a central area near the amp which I was thinking would bolster both areas (which are being fed the same music)

I didn’t want to go for much bigger speakers than the Polk Atrium 4’s as I wanted them to be more discrete (hence the thought of the subwoofer) but we could go up slightly in speaker size I suppose.

Thanks again


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@nickwild @Jzad

I reckon the receiver option is a good one. I have just done this in our Spanish Villa and I am also running the PRO in my house in UK. Multiroom Audio in Spanish Villa

@nickwild I went with Herdio Speakers as I was short for time. They are not in place yest but only time will tell. The Villa is close to the sea so a harsh environment. “Vamos a ver” as they say in Spanish. We used to have a set of “rocks waterproof speakers” but I wanted to get the speakers off the ground. I am sure the Rocks would not be a good solution on top of the pennines.

Good luck with your waterproof speaker research and let us know how you get on.

Regarding the PRO receiver the sound was probably the best source I have plugged into that arrangement. It provided a really crisp sound, plenty of punch, full range and copped very well with my 24bit 96kHz music collection. However the Rotel Preamp with the Old Skool Bose Speakers has always delivered an incredible sound.

If only Old Skool Bose Speakers were IP66 rated and Pennine Proof :joy: :joy: