'Dimmable' led downlights.

Posted by: Folkman on 27 September 2016

I know the use of light dimmers is a no-no for sound quality , but does this also apply to leds.

Im looking at some downlights with 2 stages of brightness and wondered if they work in the same way as a dimmer.

Michael.

Posted on: 27 September 2016 by Pawson6844

Yes they do, we have two above the hifi. The dimmer switch buzzes and be careful how many lights you have off each dimmer because they can flicker. 

Posted on: 27 September 2016 by ChrisSU

How about just using 2 or more sets of downlights, switched separately? 

Posted on: 27 September 2016 by Suzy Wong

We have three dimmers (one is a dual gang) in our house. I have never heard any of them buzzing and hear no effect on SQ of any of our Hifi systems.

One of them in an upstairs room drives 5 GU10 4W daylight LEDs. This dimmer came from TLC and is claimed to be a "learning/programmable" type - even comes with an instruction booklet......Hmmm......and interestingly when first installed the LEDs did flicker when dimmed down, but after a few days usage the flickering stopped. So perhaps there's something to the claim. It also has an annoying two second "soft start".

The biggest issue with dimmable LEDs is that the brightness range is cr@p compared with halogens or incandescents.

Posted on: 27 September 2016 by Mike-B

50% of the lamps in my house are LED & some are on dimmer switches,  plus I've been using dimmers on halogen (still do) for numbers of years.  Cheap &/or old tech dimmers are/can be both electrically & physically noisy. Quality modern switches are subject to regulations & are quiet, especially so those that are programmable for selecting leading or trailing edge,  problem is they can be expensive.  That said the cheapest switch I have in the house was specially recommended for my lounge (7 x 5W - 50W eq) LED's & it cost £19.  Try to buy LED's from a specialist who knows what they are talking about & have them recommend the dimmer switch.

Posted on: 27 September 2016 by Simon-in-Suffolk

Hi, yes LED lights can be notorious for electrical noise... along with solar panels. Although some more expensive designs are better filtered so I understand.. As far as I can gather it's hit and miss. Here is a short list of devices that are poor with their appropriate noise profile.

http://www.ledbenchmark.com/fa...rference-issues.html

It does tend to be FM broadcast band and DAB that can be affected as well intermodulation distortion into audio circuitry.

Posted on: 27 September 2016 by Mike-B

Simon,  i fear you are frightening the OP with that talk.  Yes I know LED's have issues with PF & switching (VR) noise & maybe significant & audible not so many years ago.  But per my previous post,  I have LED's & dimmers,  all reasonably new & to current spec standards,  & I have yet to detect any noise or SQ change between lights all on & all off.  OK some sophisticated measurement device is more than likely to find something,  but in practical listener terms does it actually cause a change in SQ ??

Posted on: 27 September 2016 by Huge

I have the same experience as Mike, however both Mike and I have taken extensive (excessive?) precautions against RFI with our systems.

Maybe this is why we don't get problems - i.e. the problems exist but are fixable.

Posted on: 27 September 2016 by Suzy Wong

Interesting, I've just put my ear up against each of our dimmers and can't hear any (physical) noise at all. Of course it could be my 60-year old hearing

 

Posted on: 27 September 2016 by Folkman

The ones I am looking at are not exactly dimmable but two 'settings' ... switch on for bright white light , switch off and on again for a lower warm level of light.   Does this work in a different way to dimming ?

It looks like a 'suck it and see' situation.

Posted on: 28 September 2016 by Simon-in-Suffolk
Mike-B posted:

Simon,  i fear you are frightening the OP with that talk.  Yes I know LED's have issues with PF & switching (VR) noise & maybe significant & audible not so many years ago.  But per my previous post,  I have LED's & dimmers,  all reasonably new & to current spec standards,  & I have yet to detect any noise or SQ change between lights all on & all off.  OK some sophisticated measurement device is more than likely to find something,  but in practical listener terms does it actually cause a change in SQ ??

Mike - its not meant to frighten - but inform - in other circles I inhabit away from this forum the EMC of these modern devices can cause real issues. Even an electrician family friend of mine is surprised at the poor performance of some devices and it has not been unknown for his customers to occasionally ask him to 'remedy' installations when the side effects of the induced electrical noise are unacceptable for what ever reason (radio, wifi, broadband, TV .. so far he has not told me about an audiophile ..yet). BTW I looked into this briefly yesterday and noticed no new tighter EMC standards. Which specs are you referring to?

But yes electrical noise is not apparent or noticeable by all - and can vary from device type and installation .... but the feedback I have its a bit of a lottery.

Simon

Posted on: 28 September 2016 by james n
Folkman posted:

The ones I am looking at are not exactly dimmable but two 'settings' ... switch on for bright white light , switch off and on again for a lower warm level of light.   Does this work in a different way to dimming ?

It looks like a 'suck it and see' situation.

It depends whether you're wanting just a change in intensity or a change in the colour temperature - if the former then dimming with a dimmer switch (suitable for the lower current load of the LED lights) is what you need. If the later then look at the something like the Hue range from Philips that allow a full palette of colours to be produced and can be integrated in with various lighting controllers (although that can get very expensive)

Posted on: 28 September 2016 by Simon-in-Suffolk

Yes the Philips devices seem to be well received - and make good home automation devices too. pricey but so far not heard of any electrical noise complaints there... I am preparing a test installation of Philips devices here (for home automation) to check for no discernible interference here

Posted on: 28 September 2016 by james n
Simon-in-Suffolk posted:
Mike-B posted:

Simon,  i fear you are frightening the OP with that talk.  Yes I know LED's have issues with PF & switching (VR) noise & maybe significant & audible not so many years ago.  But per my previous post,  I have LED's & dimmers,  all reasonably new & to current spec standards,  & I have yet to detect any noise or SQ change between lights all on & all off.  OK some sophisticated measurement device is more than likely to find something,  but in practical listener terms does it actually cause a change in SQ ??

Mike - its not meant to frighten - but inform - in other circles I inhabit away from this forum these EMC devices can cause real issues. Even an electrician family friend of mine is surprised at the poor performance of some devices and it has not been unknown for his customers to occasionally ask him to 'remedy' installations when the side effects of the induced electrical noise are unacceptable for what ever reason (radio, wifi, broadband, TV .. so far he has not told me about an audiophile ..yet). BTW I looked into this yesterday and saw no new EMC standards. Which specs are you referring to?

But yes electrical noise is not apparent or noticeable by all - and can vary from device type and installation .... but the feedback I have its a bit of a lottery.

Simon

Quite - some of the very cheap ones from the usual online suppliers and originating from the Far East can be awful - both from longevity and emissions. Add in the great antenna provided by the house wiring and these can give those awful power line Ethernet adapters a run for their money. Stick with well known brands (GE, Philips etc)

Posted on: 28 September 2016 by james n
Simon-in-Suffolk posted:

Yes the Philips devices seem to be well received - and make good home automation devices too. pricey but so far not heard of any electrical noise complaints there... I am preparing a test installation of Philips devices here (for home automation) to check for no discernible interference here

Please post your findings if you don't mind Simon - would be interested in what you find with those. 

James

 

Posted on: 28 September 2016 by Mike-B

Simon,   my point is made in my last sentence, in practical listener terms does it (LED's & dimmers) actually cause a change in SQ?    I am reasonably aware of the switching noise that most all LED lamps emit & as far as I can tell they all do to some extent; the noise is mostly in the 30-300MHz region & that can affect both FM & DAB & other domestic radio bands.  The noise emanates from the lamps SMPS & the frequency (dimming) switching unit & it seems the effectiveness of switching circuit suppression has a lot to do with the lamps noise emissions.   Cheap/low cost designs appear to be the problem in comparison to the better quality branded units.  'Which' (consumer mag) reported in 2013, "tested three 12V generic LED bulbs and we also compared them to branded 240V GU10 LEDs and some halogens. We found only a very minor interference with our radio signal. So at this stage, the issue seems to be limited to cheap knock-offs rather than branded goods".      I am aware of the concerns in your other "circles" as I have friends in the same place,  talking to one this morning he says they are concerned but its not causing issues with him personally.      James makes a point about buying quality Philips, GE etc,  good tip,  but don't assume that far east is bad, most every LED lamp from any make originates in far east.    Maybe I've been lucky,  but with so many LED's in the house - 6x 5W R63, 7x 5W (dimmed) GU10 & 4x 3W table lamps in the lounge (listening room) alone my luck tends to say its not so much luck.  My point is they have not changed any aspect of FM radio or www & local streaming SQ that I can detect.

Posted on: 28 September 2016 by Huge

Mike, Simon,

Found One!  -  You're both right!

I've found that one LED lamp I have does have an audible effect on the system (I had to test it specifically as it's in a luminère that I only use when not listening to music).

All the others (Osram and one from Morrison's) are fine.

Posted on: 28 September 2016 by Simon-in-Suffolk
james n posted:
Simon-in-Suffolk posted:

Yes the Philips devices seem to be well received - and make good home automation devices too. pricey but so far not heard of any electrical noise complaints there... I am preparing a test installation of Philips devices here (for home automation) to check for no discernible interference here

Please post your findings if you don't mind Simon - would be interested in what you find with those. 

James

 

will do - its linked to some illuminated drive way and pathing at the from of the house - some of the wiring in - but progress is on a strictly out of hours basis - so not fast.

What I will say in my experience is that flat screen TV interference has improved generally. 10 years ago there used to be some howlers but these days things seem to be better - its probably due to cheaper plasmas have been largely replaced by LCD/LED and ethernet over power line  is losing favour. I used to be able swing my beam over the direction of the village and pick out some atrocious noise sources - now its less pronounced though there a slightly greater intensity general noise level. The one exception is solar panels - when the sun comes out larger, and I assume cheap, roof top deployments can be very noisy.

 

 

Posted on: 28 September 2016 by Phil Harris
Simon-in-Suffolk posted:

Yes the Philips devices seem to be well received - and make good home automation devices too. pricey but so far not heard of any electrical noise complaints there... I am preparing a test installation of Philips devices here (for home automation) to check for no discernible interference here

I'm using the Philips Hue stuff myself in the annex where I live - mainly to get round the really poor placement of light switches etc.

Absolutely no issues with brightness from any of the actual 'bulbs' (although the colour capable bulbs aren't as bright as the 'white' bulbs) but the 'bloom' isn't as bright and is definitely an 'accent' light rather than a room illuminator.

The colour changing bulbs and the bloom don't have the same colour ranges ... they seem to differ quite substantially in their handling of greens/blues but it's only an issue if you want to specifically plunge yourself into a completely green or blue room.

Looking forward to seeing how well the Amazon Echo integrates in with Hue...

Phil

Posted on: 28 September 2016 by Simon-in-Suffolk
Phil Harris posted:

Looking forward to seeing how well the Amazon Echo integrates in with Hue...

 

exactly 

Posted on: 28 September 2016 by Ardbeg10y

Interesting topic. I've currently 7 Hue bulbs (4xGU10 / 3xE35) and plan to change over time all my bulbs by it. 5 of the bulbs are on the same mains ring circuit as my audio gear therefore I would appreciate to see any findings on this topic.

Posted on: 28 September 2016 by james n

Out of interest - Why are your bulbs on the same ring rather than on a lighting circuit (or is it just for some display cabinet ) ?

Posted on: 28 September 2016 by james n
Simon-in-Suffolk posted:
james n posted:
Simon-in-Suffolk posted:

Yes the Philips devices seem to be well received - and make good home automation devices too. pricey but so far not heard of any electrical noise complaints there... I am preparing a test installation of Philips devices here (for home automation) to check for no discernible interference here

Please post your findings if you don't mind Simon - would be interested in what you find with those. 

James

 

will do - its linked to some illuminated drive way and pathing at the from of the house - some of the wiring in - but progress is on a strictly out of hours basis - so not fast.

Cheers Simon. 

Posted on: 28 September 2016 by james n
Mike-B posted:

  James makes a point about buying quality Philips, GE etc,  good tip,  but don't assume that far east is bad, most every LED lamp from any make originates in far east.   

You're right Mike a bit of a generalisation by me there so i stand corrected. I should have said the bargain Far East lamps. Having had a look inside some of the ones that fail early, the build is just shoddy (soldering mainly) and inadequate heat sinking around the driver / LED substrates. False economy. 

Posted on: 28 September 2016 by Ardbeg10y
james n posted:

Out of interest - Why are your bulbs on the same ring rather than on a lighting circuit (or is it just for some display cabinet ) ?

Good question. We bought a house last year build in 1926. For the central lighting point in the ceiling was no switch. It was always on, so when I put a bulb in it, it was immediately on. To easily fix it, I bought the just released Hue Dimming Kit. Put the Hue bulb in it, and from that moment on I could control it by phone and the Hue dimming switch.

Other 4 bulbs are in my study which was renovated in the spring. To avoid all kind of drilling in the walls - but still willing to have 4 GU10 spots in the ceiling, I have chosen to have them connected on the mains embedded in the ceiling and only control them using phone.

So, all these 5 bulbs are always connected to the mains ring and fully controled by phone / dimming switches.

I'm not so worried for these Hue bulbs, but a bit more for my older dimming switches in the room. They came with the house and I feel more and more the need to try to find a relation between the dimmers / fridge / microwave / hairdryer / samsung adapters for my kids devices and the loudness of purring of the transformer of my supernait. Normally it is calm but audible, but now and then it gets crazy and is begging for attention. Assumed relation here to the other devices on the mains.

Posted on: 28 September 2016 by jon h

Am having great fun with the Philips Hue system. Works very well, so far v pleased. No effects noted on the Dibbles so far.