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Cheap 2 Channel amp with auto on/off - in the uk?

philjeary

Standard Member
Hi all,

I'm after a 2 channel amp for 8ohm speakers with auto on/off. I've found a few, such as the AudioSource Amp-50 (http://www.amazon.com/dp/B004U29IGG), but they all seem to be American models.

The closest i've found in the UK is the Yamaha as300, which is about £150 more expensive than the model above and its "auto" off shuts off 6 hours after its been used - which isnt really the "auto" i was after.

Does anyone know of an amp like i've described that is available in the UK?

Any help would be much appreciated.

Kind regards,
Phil
 

MaturityDodger

Prominent Member
What exactly is your use case here? I might have a couple of ideas for you depending on exactly what you're doing.

But to directly answer your question, here's what I can see that has auto-standby. (you can decide for yourself which ones are 'cheap'!)

Pioneer A10 (£150, standby after 30 mins of no audio signal)

Actually that's all I can see. I was hoping for a longer list.
Anyway, I suspect you might not need to go down this route, depending on exactly what you're doing.
 

Don Dadda

Distinguished Member
The closest i've found in the UK is the Yamaha as300, which is about £150 more expensive than the model above and its "auto" off shuts off 6 hours after its been used - which isnt really the "auto" i was after.


Hi, a bit more info please

What kind of "auto" shut off are you after?
 

philjeary

Standard Member
Thanks for your replies.

Don Dadda, the auto on/off I was looking for would wake the amp up from standby when an audio signal is detected, and put the amp to sleep after a set period of no audio signal to the inputs - ideally after a few minutes rather than 6 hours.

audioenthusiast, thanks for the Pioneer tip, that sounds slightly more ideal than the Yamaha I was looking at (by about £50 less and 5.5 hours of the amp being on).

In short - it's for "zone 2".

I have 2 8ohm speakers on the wall in the kitchen. When I switch on zone 2 on the amp in the front room, I would prefer to have an amp for the speakers in the kitchen that switches itself on, then off again after a short period of no signal.
Initially that wasn't necessarily part of the spec, but after finding models in the US that have no other bells and whistles, but have auto on/off and cost about £50, it seems odd that there aren't similar options (i've found so far) in the uk.
 

MaturityDodger

Prominent Member
I was hoping you'd say something like that!

In that case, have you thought of doing the power management externally?
I have one of these: 2 PowerDown Standby saver plugs, Made By OneClick IntelliPlug DSK105 for e-On 5055116800001 | eBay (you actually get two in the pack, so maybe use another on a computer/peripherals)

Plug your main amp into the master socket.
Plug a multi-power strip into the peripheral socket. This zone 2 amp and maybe other things can go into the power strip.
When you turn your main amp on/off, the standby socket will cut power completely to the power strip.

It works by detecting the amount of power used by the main amp, and it sets its ranges automatically. I have one of these on my TX-NR709, setting power to the sub and to a wii. Works perfectly.
For you, it'll mean that your zone 2 amp comes on whenever you take the main amp out of standby for use in either zone. But I don't think that's too much of an issue?

What sort of amp are we talking about for your main amp? An AVR, I guess?
 
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philjeary

Standard Member
Nice suggestion - it wouldn't quite work for my situation as I have the main amp on most of the time, and only really have zone 2 on when i'm doing the washing up.

However, part of your set up made me realise that I wasn't thinking it through properly. Because my speakers are in the kitchen my train of thought was that is where the amp for zone 2 would also go. If I put the second amp in the same place as the first, my main amps remote can control that too. Turning on amp2 at the same time as amp 1 isn't such a hardship.

I'll keep looking for a uk version of the link in my first post for a while, but at least I have some more options and can avoid having a remote lying round the kitchen.
 

MaturityDodger

Prominent Member
Or get a universal remote, and you can have the zone 2 amp switch itself on in the same button-press as the AVR switches to z2!
Also, I'd be happier running speaker cables for a distance from one room to another than I would for line-level signal cables.
And by putting the amp in the lounge, then that's one less piece of equipment to risk damaging in a potentially moist/steamy kitchen.

Although I must say, I had assumed you were talking about controlling the main amp remotely from the kitchen. I had assumed a network-enabled amp or something.
 

barry7767

Established Member
I imagine you are sorted, but this seems to fit the bill:

Pre Beat

I have a spare Sonos Connect (not the amplified version) and plan on using it in loft - looking to connect to a simple stereo amp with the same auto on/off you require to power a in ceiling bathroom speaker.
 

riccume

Standard Member
Bump. I have the same need: currently my ceiling speakers are connected to 'Zone 3' of my AV Receiver (with signal coming from an AirPort Express via Cambridge Audio DacMagic) but my wife gets really confused by the current set-up. I'd like to move to Chromecast Audio connected straight into cheap 2-channel amp with auto on/off i.e. auto sensing. I understand the Audiosource Amp100, Pyle PAMP1000, and Pioneer A-10 would all fit the bill as amps (in particular the auto on/off) but was wondering if there is any other <£100 amp which I should check out. Thanks!
 

Goodmane

Established Member
@ riccume

I have considered the Audiosource amp100 but based on my limited electronics knowledge it may not work or would be dangerous to be used in the UK due to the voltage not being compatible with 240v power. I could see no mention of 'up to 240v' on the back of the unit from looking at photos.

Perhaps Audiosource could inform you / me directly but as I understand it, you generally have to buy power adapters with big transformers in them. For a 500w load, you're looking at about £80 I think for a 240v to 117v transformer adapter, and I couldn't find any that seemed reliable according to reviews either.

If someone could let me know if I'm wrong that would be great, as I would also like a small amp for my PC (always on for file serving etc) that could power on and off automatically as required.

I think my current solution (an old Yamaha stereo amp) might be using as much as £200 worth of electricity every year if it were always on? I would love auto on/off as per Audiosource Amp100 but the Pyle unit seems unreliable and runs hot apparently. I may just get a small class T amp instead and leave it on all the time. There's a nice one from Topping 2x25w that also has a usb dac in it. Not ideal regarding power as not auto on/off, but probably much better than the big brute I'm currently using.

Edit: there seem to be a few potential USA amps that I think will work with UK power. These include the Niles SI-250, which I think has 12v power on, as well as line sensing auto on/ off, but it's not cheap. The only cheap option for the UK is from Pyle and it has one too many reviews indicating it can catch fire / spark / die.

If anyone discovers the much cheaper Audiosource Amp100 is safe to use, please let us know, I may contact the manufacturers myself at some point.

Edit #2: Audiosource have a newer model the Amp102, cheaper than the Niles, which appears to work with 230v, 50hz power sources. I'm not sure that it would work in the UK with a simple adapter, but it would probably be a better route of enquiry than the amp100 which does not have such a mention on its backplate photos.
 
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riccume

Standard Member
@Goodmane
All good points, thanks. I reached out to Audiosource, they replied very promptly, kudos to them! Long story short - one can either buy the AMP102 and change fuse plus use a plug adapter (small fry) or buy the AMP100 + 500W step-down transformer (not worth it if you have to buy it - GBP 50 - but I already have one).

The full reply:
The AMP100 is not configurable for 230V power.
The AMP102 is configurable for 230V power and is an equivalent product to the AMP100; there is low stock available in distribution. I believe at this moment there are 5 available at Amazon.com.
Please note you will need to buy the correct IEC line cord and replace the fuse, and switch the mains voltage switch to the 230V position. Detailed instructions come in the manual for doing so (fuse values are noted on the back of the unit also).


To my questions about using a 1kW transformer I already have:
Yes, you could use a step down transformer, a 1K Watt stepdown transformer should work fine, and 50Hz should not be a problem at all.

At $160 the AMP102 might be a better option than the Topping 2x25w at GBP 80, right?
 

Goodmane

Established Member
@ riccume, thanks for confirming that, and letting me / us know. Without wishing to get fuzzy, sometimes I really do love humanity.

I guess the Amp102 is the better option over a couple years of use if the Topping would be left on all the time, and you are not going to end up buying an alternative usb DAC. But it may be harder to source one, and you have to factor import costs and hassle with returns if its faulty. I'm currently debating it myself, I could do with assurances that my data is not too far off, i.e. that 1watt-hour per year costs around £1. If that is correct then we're better off saving power; if electricity is much cheaper, then the Topping may be the better option.

Please do let me know if you find a good way to get hold of the Audiosource Amp102.
 

riccume

Standard Member
@Goodmane I believe your calculation is correct, 0.01kW x 24h x 365d x 10p (cost of 1kWh) is c. £1. So Topping might well be an acceptable option. It is only 2x25W though, not sure it'll be loud enough. Also I'd think the Audiosource deliver better audio quality. With that said, the Audiosource is a major pain to get (I was thinking of getting mine next time I go to the US and put it in the carry-on luggage), the Topping is only one click away on Amazon! One could easily buy one, check it out, and if not OK return it...
 

Goodmane

Established Member
Thanks. I had a look at the Topping website. They have usb on/off so if you turn your PC on/off the amp will sync with it. That seems like a good solution, although its not great for me.

I like to keep my PC on; yes it uses a lot of power over the year, but its worth it to me not to deal with finickety WOL apps, and it then not turning on when required. I've contacted Topping to see if they are interested in developing their on/off functionality. Will report back if I hear anything.

The only thing stopping me from buying at the moment is that I would prefer the Audiosource / Niles solution, and they may also work out cheaper over the long term, as well as potentially being more reliable (for being bigger and perhaps cooler / easier to fix) as well as being more powerful.

Edit: does anyone know how the auto on/off usb might work with usb selective suspend in Windows? Might it turn off the power when not required, and if so, will it come back on again when sound is played through it? My experience messing around with usb power settings has not been positive in the past, but others may have had better luck?
 

Goodmane

Established Member
@ bgst Thanks for posting. That would do the job.

For me, there are a few deal breakers though:

1. Total harmonic distortion (THD) is specified as less than 2%. On pure direct amps / power amps THD is usually around 0.02-0.04% or something small like that. I easily notice and dislike the jump to 0.08% on the same amps when tone controls are not bypassed. I can cope with around 1% for the PC at the right price, but 2% is hard to swallow at the price of around £105.

2. Minimum 50hz input suggests will not work well with bass, subwoofers are expected to go down to 20Hz or at least 30Hz for example. I can cope with 50Hz or even 80Hz (the specified lower frequency limit of my current PC speakers) but again, not for that price, for me at the moment.

3. Cheap looking remote control, confirms the presence of tone controls (bass / treble) which based on the cheap looks of the remote may well be poor quality components leading to huge loss of sound clarity.

I thought I should post these comments to help any others thinking about buying one of these units. But I should just like to say how grateful I am that you posted. It is good to know that such a unit exists in the UK, I just wish the specs and feature set suggested better sound quality. Thanks again.
 
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bgst

Standard Member
Yeah I noticed that too. They got a 100w version as well which has a bit better specs (frequency range and distortion) but still a bad SNR. I suppose this isn't a HIFI amp but targeted towards meeting rooms, schools etc.
 

Goodmane

Established Member
Well, I found out that Class D amps are more efficient than I thought. I will probably get a meter at some point for more information on my specific unit, but apparently it could be using a mere 5 to 35w when idle and turned on. I can live with that given the increased power of the unit and the quality, reliability and repair ease of the Yamaha.

I'd like to negate any fire risks and reduce power, but I think I'll wait a little and see what I can find out or make. I think home audio appreciation is a hobby well suited to going on an electronics course. :)
 

brjhaverkamp

Novice Member
I found this topic while searching for a bedroom/badroom speaker setup.
I'd like to have them always on and connected to a raspberry pi board, so I can just steer music to them or use them for an alarmclock.
What is the idle power of a class d amp. Does it make sense to use one of the cheaper ones like the
Pyle PCAU22 or even one of the Lapai's you see everywhere on ebay?
 

Goodmane

Established Member
I think the answer is that it depends on the specific amp. If you have access to a smart meter at your house or someone elses, you might be able to test. I found one thread with some examples as low as 3 watt-hours. So probably 5 euros per year up to about 100 euros depending on the amp.

For me personally, I would make sure it doesn't get to hot, or have cheap components as I believe there is a risk of fire with any electrical item left on all the time. A fire would be more expensive than powering an amp for decades.
 

brjhaverkamp

Novice Member
I was hoping to get some reference measurments here, before I dive in and buy one.
But even with 3W, it makes sense to switch it on and off. The Raspberry Pi is especially suitable for that, With a cheap Solid State Relay circuit, I can switch the amp on before the music starts and shut it off after some timer expires. The code for that is very easy with Python.

What is the quality of the Pyle or the Lapai? Are any of the 40$ class D's worth considering these days? Or should I move to a higher segment? Mind that I am using them in a bathroom and walkin closet anyways:)
 

Goodmane

Established Member
I agree it would be nice to know. But I don't have any figures to offer I'm afraid. Others might chip in however you might get more answers asking Pyle or Lepai directly or just looking at the specifications on their websites.

The SSR circuit sounds great. If you could configure it so that it comes on with voltage sensing and then stays on for around 4 hours (a long movie plus extra just in case to prevent it turning off during quiet moments) then you would have a perfect solution. Even better if you can figure out a way to put it in a power plug adapter because then you could use any amp you want with it.
 

riccume

Standard Member
Has anybody considered the SMSL SA-50? Class-D amp with rave reviews on Amazon, 2 x 50W, <1W idle consumption so no big deal to leave it on all the time, and costs only £50 in the UK or $65 in the US. Sounds like a very good solution to me! Thoughts?
 

Goodmane

Established Member
Thank for the heads up. Actually I got the impression that pretty much all class D amps will have fairly low power draw in idle so I'm sticking with the big old reliable Yammie. But your suggestion makes a lot of sense for someone who does not already have an amp, assuming it sounds good and the price stays competitive.

I think people will start collating info online when electricity smart meters become mandatory (to be provided by your utilities company) in a couple of years.
 

riccume

Standard Member
Which Yamaha you're referring to? The Yamaha ax392? But that's Class A/B, right? As you said a while back, it costs a lot of money to leave it on all the time - which is what I want to do (either by purchasing an amp with auto-sensing, or one with very low idly consumption).

It is also my understanding that Class D amps are all very efficient and have low power drain in idle. The catch is (as far as I understand) that there is a huge spread of sound quality for Class D amps, depending on the electronics surrounding the core Class D amplifying circuitry. So, short of good professional reviews (these amps seem to be too low quality / cheap for HiFi reviews) I used Amazon reviews as a proxy. On that basis the SMSL SA-50 seems to be one of the best...
 

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