LED Pars

[Skumling]

Okay, okay Bruce - I'll post my answer regarding the LEDs here, then :D

 

 

The majority of the cheap LED stuff comes from a single manufacturer in deepest darkest china, and as a result the build quality is exactly the same, on occasion the software is slightly different but some OEMers can't even be bothered to change that.

 

I will suggest the OP to check out JB Systems LED par64 ( http://www.beglec.com/products.php?product=94971&lang=EN ). I decided to try a couple of LED par64's, and ordered 2 of the JB's and 2 Eurolite PAR64 LEDs ( http://www.thomann.de/gb/euroliteled_par_6..._10_mm_leds.htm ). I'll try to list some of the differences between these two equally prices fixtures:

• JB fixture has a wider beam angle (37°), which serves my purpose better. The Eurolite is specified at 36°, but it seems a lot narrower than the JB. I don't know which of the two is providing the wrong info, but there are certainly a big difference on the two.
  
• In clean colors the Eurolite has a bit better blue, the JB has better green and red - they simply seem a bit deeper.
  
• When mixing colors, I tend to like the JB better, especially on magenta-ish colors, even though it has got quite som artifacts in the beam edge. JB has provided me with info that the next batch of fixtures will come with support for filters, so you can put a frost on it and that way soften the edges. The Eurolite doesn't have these artifacts, and produces a more clean mix, but somehow I still like the JB's better. When sending the same RGB values to the two fixtures, there are very huge differences in the produced output!
  
• JB housing is smaller, it seems kind of unnecessary to make it as big as the Eurolite ones is.
  
• Even though I didn't have any high expectations to the JB, I'm actually a bit impressed of the build quality when compared to the Eurolite. I took both of them apart, and the internal PCB's, mounting and general construction seems more rough on the JB. On the Eurolite, the metal plate the trafo is mounted on actually is starting to bend, even though I have never used them yet. I don't it actually will break, but the construction certainly doesn't seem any solid.
  
• I expected the Eurolite to be a bit brighter than the JB, but in fact I'm doubting that it actually is. The JB contains 212 50mm "high power" LEDs which is more than many other fixtures (e.g. the Showtecs) which ships with 151 LEDs whether they are bought as par56 or par64's. The Eurolite comes with 183 10mm LEDs, but I don't think it's brighter, I just think that it's got a narrower beam.
  
• One giant minus (in my opinion) on the JB is that when it looses its DMX signal, it will fall back on music triggering via an internal microphone. In theatrical environments and the like it's obvious that you don't want things to start blinking, if you need to reboot the controller, unplug a DMX wire before show-start etc.
  

One point where I can't compare to the Eurolite, is the support. I didn't use Eurolites. But today I wrote to Beglec (who owns the JB brand), and I'm truly impressed about their fast response and attitude in general. They will consider making it possible to disable all the internal control (music trigger and master/slave mode). I got two answers from them in only two hours from the first time I wrote them, and they took me very seriously although at first they couldn't see the problem in falling back to music triggering, because they mainly operate in the club/dance/disco-market. I managed to convince the supporter that it would be more professional, if these internal functions could be disabled. He would talk to the developer, and maybe provide a jumper on future PCB's. I really hope they would do that! With filter support and this problem solved, I wouldn't be in doubt of which of the two fixtures to go for.

[Ekij]

In clean colors the Eurolite has a bit better blue, the JB has better green and red - they simply seem a bit deeper.

When sending the same RGB values to the two fixtures, there are very huge differences in the produced output!

These are mega-cheep units which use the bottom of the range LEDs.

when LEDs are manufactured they are 'binned' in accordance with the quality, frequency and light output. The ones that are exceptionally poor end up in these sorts of applications and therefore the quality of light is going to vary from LED to LED in the same unit, let alone two units off the production line one after the other let alone trying to compare different units.

Unless your sample size is large I wouldn't be confident that difference between manufacturers is significant and even if it is additional units ordered later will be made with a different batch of LEDs and are unlikely to be the same as the previous batch.

 

If you want repeatable quality of light between units you need to buy the expensive stuff.

[guitarperson]

People using sound to light function with no controller:

 

How do you comtrol the sensitivity of the lamps. I find that they change faster as the music gets louder, and at gig levels they just flicker uselessly in constant white.

Has anyone ever modded their circuit to add a sensitivity control?

[gnomatron]

Some of the cheap LED pars come with a sensitivity control built in - the ones I acquired recently certainly did.

 

One of the major disadvantage of these fixtures in general is that I simply can't tell you the make of them because I don't know; I bought through a reputable supplier, but the fixtures didn't come boxed or with any sort of proper manual, they simply had a single sheet with some instructions.

 

That said I was pretty pleased with them, using them as ambient lighting in a nightclub. I'll not be binning my battered old proper pars any time soon, though, but then I wouldn't be putting them up 2 feet above customers heads either.

 

Cheap LED stuff might look like a parcan, but it definitely isn't - for better and worse.

[guitarperson]

These ones were certainly cheap, but unfortunately they don't have that control. I'm hoping somebody somewhere will have a schematic so I can (with luck) change a resistor for a potentiometer and bingo - a sensitivity control.

I'm really being mean - I think I could get a useable DMX controller for £160 and my troubles would be over.

 

Anyhoo - like yours, mine have no make, and the 'manual' is a single sheet of paper with no clue as to who supplied it.

 

The PCB has:

 

AGT-PAR

 

on it in big letters. Does anyone know where I should go looking for a schematic?

[Brian]

on it in big letters. Does anyone know where I should go looking for a schematic?

I have a schematic but it's hand-drawn. If you've got a bit of electronics knowledge - you need to find the 2k resistor which is in the collector of one of the 2 2SC331 transistors and which also feeds the capacitor whose other end connects to pins 1 and 2 of the 4093. Replace that with a pot, with the wiper now feeding the capacitor, and you have a sensitivity control.

 

The whole sound side is just an electret mic followed by a 2 transistor amplifier which is capacitively coupled into a schmitt trigger whose output goes to one side of the sound/auto changeover switch.

[guitarperson]

Brian,that is excellent - exactly what I need. I'm embarrassed to say that I do have some electronics knowledge, but I'm lazy and WAY out of date. I'll let you know how I get on with this.Cheers,Craig

 

(2 hrs later)

Well,I found that resistor - its 20K on my version. I put a 500K pot in series with it and unfortunately it made no difference - either end of its travel - just the same.I think I'll try putting it in series with the mic next. Watch this space.

 

I don't suppose you could scan the schematic & send it as a pdf ?

[Brian]

Before...

After version 1...

After version 2...

[guitarperson]

Thanks Brian,

mod number one didn't do it - the sound to light circuit stopped working altogether. Mod number 2 did have an effect, unfortunately, it didn't slow the rate of flashing in response to sound - all it did was at a certain threshold value of adjustment, freeze the lamp on a certain colour.

I think my next experiment will be to have a very narrow range of adjustment just around that threshold value. I'll put a 200R pot in series with a resistor. If thats no good I'll go back to trying to turn the volume down at the mic end ofthe circuit.

Thamnks again,

Craig

[stoochy1]

hey guys. I am looking to get some new LED's. Ive read all 28 pages of information and still am confused. Is thoman STAIRVILLE PAR 64 LANG ALU POLIERT BUNDLE a good deal. on page 8 a member posted pictures of some pars, what I dont know is how did he get the great narrow light beam. can someone please help me out. I need to make a purchase for a portable church quickly and dont know where else to turn to. thanks

[niclights]

The bundle you mention is for normal incandescent PAR 64. At a glance it appears to be for 500W 'raylight'. It's probably not a bad deal if it's what you want - very narrow beam with noticeable hole in the centre.

 

For LED's were you referring to my photos on page 5?

 

The beams are as they come - I doubt it would be any different for any of the various cheap offerings in 56 or 64 size bodies. Note that, though the beam is reasonably narrow, the throw there is only approx 10' from lantern to floor.

[Caldair]

• JB housing is smaller, it seems kind of unnecessary to make it as big as the Eurolite ones is.

Wouldn't that make one of them a PARsomethingelsethan64? ;)

 

• One giant minus (in my opinion) on the JB is that when it looses its DMX signal, it will fall back on music triggering via an internal microphone. In theatrical environments and the like it's obvious that you don't want things to start blinking, if you need to reboot the controller, unplug a DMX wire before show-start etc.

If you unplug the microphone, would they hold their last state (like we'd want them to), go dark, or go crazy?

 

 

Can anyone tell me if the early posts in this thread (being three years old by now) are still up to date on performance?

[stoochy1]

nic, yes thats exactly what I was referring too. I love those pics. so the narrow beam has to do with the distance from light to surface? I didnt know that. anyways, does the bulb make a huge difference? teralec.com sells par56 for about 19 and the bulb for 19. but thoman is way way cheaper, but I wasnt sure if it was one of those you get what you pay for.

 

thanks for the advice.

 

dg

 

http://www.thomann.de/gb/stairville_led_pa...alu_poliert.htm

 

would this be worth it. they are a little bit more but seem worth it. also, how much are replacement bulbs comparibly. I dont want to get a super duper nice light if the bulb is a fortune. thanks

[niclights]

I mentioned distance so you understood the scale, that's all.

 

You seem confused. There are no bulbs for LED. That's one of the great things about them! The unit in the link is effectively exactly the same as the one in my photos. The only differences will be subtleties in control and possibly the maximum DMX address available.

 

For future reference it is generally thought false economy to buy cheaper lamps because of reliability. You always get what you pay for!

[Chris Adam]

As a little side note. I'm getting rid of some Thomas Pixeline 1044s to free up a bit of cash for the venue, but quite fancy giving some cheap LED floor cans a bash. My big question is: do you reakon AVO will have a fixture personality for the cheap ones so that I can just bung them straight into a pearl?