GreeneKing Posted December 20, 2019 Share Posted December 20, 2019 My Fafner I is proving to be an awesome amp into just one of my two 8ohm Accugroove Tri112’s. On Tuesday the amp started to cut out and the gain control was inconsistent. After about 15 minutes it sorted itself out. I have been storing it in an unheated conservatory and I wondered if the problem may lie in that? I had a spare valve so fitted that in any case. A bit of a fiddle from the front panel due to large fingers and switch wires an inch too short.... It’s now behaving but the orange glow has gone. Does anyone have a link to a replacement lamp/bulb to save me taking it apart again, twice? Peter Quote Link to comment Share on other sites More sharing options...
thodrik Posted December 20, 2019 Share Posted December 20, 2019 (edited) 5 hours ago, GreeneKing said: My Fafner I is proving to be an awesome amp into just one of my two 8ohm Accugroove Tri112’s. On Tuesday the amp started to cut out and the gain control was inconsistent. After about 15 minutes it sorted itself out. I have been storing it in an unheated conservatory and I wondered if the problem may lie in that? I had a spare valve so fitted that in any case. A bit of a fiddle from the front panel due to large fingers and switch wires an inch too short.... It’s now behaving but the orange glow has gone. Does anyone have a link to a replacement lamp/bulb to save me taking it apart again, twice? Peter Contact EBS and they can ship you a replacement bulb directly. Any lamp of the same type will work though, it just won’t have that red/orange glow. In terms of the amp cutting out, the valve and the lamp should not be causing this. The lamp is purely cosmetic, the valve is only inserted into the drive system so if it blows the rest of the amp should still work. I kept my Fafner stored in an unheated rehearsal space for nearly three years. It is still working. So I don’t think that the environment you are storing the amp in is hurting it. It might be worth taking the amp to a tech to have a look. The Fafner I amps are great but they have been discontinued for years. Some parts to the existing amps will eventually start to wear out. I would agree though that the gain control is finicky. Changing the EQ setting or adding or cutting drive generally has a big impact on the signal so you have to add to reduce the gain to suit. Of course once you change the gain level this again changes the character of the drive signal... Great amp though! Edited December 20, 2019 by thodrik 1 Quote Link to comment Share on other sites More sharing options...
EBS_freak Posted December 20, 2019 Share Posted December 20, 2019 Forget the bulb. Replace it with a LED and resistor. It'll never fail (you'd hope) again. You can then have whatever colour glow you want (well, if you can find the appropriate coloured LED). 2 Quote Link to comment Share on other sites More sharing options...
thodrik Posted December 29, 2019 Share Posted December 29, 2019 On 20/12/2019 at 11:37, EBS_freak said: Forget the bulb. Replace it with a LED and resistor. It'll never fail (you'd hope) again. You can then have whatever colour glow you want (well, if you can find the appropriate coloured LED). What kind of LED and what kind of resistor? I think I need to do this mod. Bulb had gone for the umpteenth time at a gig... Quote Link to comment Share on other sites More sharing options...
EBS_freak Posted December 29, 2019 Share Posted December 29, 2019 1 hour ago, thodrik said: What kind of LED and what kind of resistor? I think I need to do this mod. Bulb had gone for the umpteenth time at a gig... I forgot off the top of my head. Can you tell me what’s written on the bulb? I can give you the required if you give me the spec. (blue LEDs always look great in a Fafner) 1 Quote Link to comment Share on other sites More sharing options...
thodrik Posted December 30, 2019 Share Posted December 30, 2019 1 hour ago, EBS_freak said: I forgot off the top of my head. Can you tell me what’s written on the bulb? I can give you the required if you give me the spec. (blue LEDs always look great in a Fafner) I will do! Much appreciated. Quote Link to comment Share on other sites More sharing options...
thodrik Posted December 30, 2019 Share Posted December 30, 2019 14 hours ago, EBS_freak said: I forgot off the top of my head. Can you tell me what’s written on the bulb? I can give you the required if you give me the spec. (blue LEDs always look great in a Fafner) Hi, just checked the bulb, which is a 42v 2w 45MA bulb. It is about the fifth bulb I have gone through in ten years. Feel free to give me a PM or so with what bits I need. A blue LED would look far better. Many thanks again! Quote Link to comment Share on other sites More sharing options...
EBS_freak Posted December 30, 2019 Share Posted December 30, 2019 25 minutes ago, thodrik said: Hi, just checked the bulb, which is a 42v 2w 45MA bulb. It is about the fifth bulb I have gone through in ten years. Feel free to give me a PM or so with what bits I need. A blue LED would look far better. Many thanks again! Ah yes, I remember now. EBS always tend to use weird voltages - same with their fans. http://led.linear1.org/led.wiz Using the above, you'll be able to arrange a 6 blue LED array. (42v, 3.3, 20, 6 as the inputs) Solution 0: 6 x 1 array uses 6 LEDs exactly +42V R = 1200 ohms The wizard says: In solution 0: each 1200 ohm resistor dissipates 480 mW the wizard thinks 1W resistors are needed for your application together, all resistors dissipate 480 mW together, the diodes dissipate 396 mW total power dissipated by the array is 876 mW the array draws current of 20 mA from the source. To be safe, I'd get a 1.2k Ohm resistor with 1W rating. 1 1 Quote Link to comment Share on other sites More sharing options...
thodrik Posted December 30, 2019 Share Posted December 30, 2019 6 minutes ago, EBS_freak said: Ah yes, I remember now. EBS always tend to use weird voltages - same with their fans. http://led.linear1.org/led.wiz Using the above, you'll be able to arrange a 6 blue LED array. (42v, 3.3, 20, 6 as the inputs) Solution 0: 6 x 1 array uses 6 LEDs exactly +42V R = 1200 ohms The wizard says: In solution 0: each 1200 ohm resistor dissipates 480 mW the wizard thinks 1W resistors are needed for your application together, all resistors dissipate 480 mW together, the diodes dissipate 396 mW total power dissipated by the array is 876 mW the array draws current of 20 mA from the source. To be safe, I'd get a 1.2k Ohm resistor with 1W rating. Many thanks. I will try and get my head around the maths and electronics (not my strong suit) but I’m definitely going to do it! Cheers! Quote Link to comment Share on other sites More sharing options...
EBS_freak Posted December 30, 2019 Share Posted December 30, 2019 (edited) Here you go - https://www.ebay.co.uk/itm/50-100pcs-3mm-5mm-LED-Diode-Clear-White-Red-Blue-RGB-Light-Emitting-Diodes-Lamp/202717758478?var=502845008360&hash=item2f32eb840e:m:miGcURJ96LGXGEFlCh0UjOQ Using the specs in the listing - Color Lens Type Dominant W avelength (Unit:nm,IF=20mA) Forward Votage (Unit:V,IF=20mA) Luminous (Mcd) Viewing Angle 2θ 1/2 Typical Typial Max Red Water Clear 620 2.0 2.2 10000 30 Orange Water Clear 600 2.0 2.2 6000 30 Yellow Water Clear 585 2.0 2.2 6000 30 Green Water Clear 520 3.0 3.2 8000 30 Blue Water Clear 468 3.0 3.2 8000 30 Purple Water Clear 395 3.0 3.2 400 30 White Water Clear 6000-6500k 3.0 3.2 12000 30 Warm White Water Clear 3000-3500k 3.0 3.2 14000 30 Pink Water Clear x=0.38,y=0.18 3.0 3.2 8000 30 I've highlighted the line in question so the figures are in red. Using the array calculator (inputs 42v, 3.2, 20, 6)... you'll still get the same result. So these LEDs are good. As I say, make sure you get the right resistor though. Is not too hard - for chaining LEDs, solder the shorter leg, the cathode (negative), to the longer leg, the anode (positive) of the next LED. Make sure you heatshrink to prevent shorts. R Edited December 30, 2019 by EBS_freak 1 Quote Link to comment Share on other sites More sharing options...
GreeneKing Posted January 16, 2020 Author Share Posted January 16, 2020 I've bought some blue LED bulbs on eBay, less than £4 for 5 all the way from China. They are 36v so may prove unsuitable. I'll update.. 1 Quote Link to comment Share on other sites More sharing options...
EBS_freak Posted January 16, 2020 Share Posted January 16, 2020 (edited) Don't use those unless you want to release some magic smoke. Also, if you take the lid off, you may want to give the pots and valve bass a sprinkling of servisol. Edited January 16, 2020 by EBS_freak 1 Quote Link to comment Share on other sites More sharing options...
Graham Posted January 16, 2020 Share Posted January 16, 2020 If you live anywhere near Brighton, take it into Bernie Goodfellow who'll do the LED mod for you at a reasonable price - he did it for my old Fafner, you can pick the colour too😀 1 Quote Link to comment Share on other sites More sharing options...
GreeneKing Posted January 20, 2020 Author Share Posted January 20, 2020 An update; I took the top off and the amp is very clean. The guy I bought it from told me that it had recently been serviced but shipping always carried potential for damage. I checked all connections that I could get to and used Servisol on the pots (from the front with knobs and nuts removed) and the valve base. I've had it on for over 4 hours now with the blue LED lamp fitted and all is good. The blown incandescent lamp that I removed was a red 'painted' 48v. I've sourced a UK made red 48v LED at RS Components and it arrived today. £7.25 with free delivery. However with the blue one working so well I may just leave it in. Practice tonight but fingers crossed. Quote Link to comment Share on other sites More sharing options...
EBS_freak Posted January 20, 2020 Share Posted January 20, 2020 Looks great. I always thought the Fafner looks better with blue lights on the right anyway... but each to their own! 1 Quote Link to comment Share on other sites More sharing options...
EBS_freak Posted January 20, 2020 Share Posted January 20, 2020 Also @GreeneKing - the blue LED in there to which you refer - are those the ones from the post further above. If so, it would seem that the voltage on the Fafner light is not 42v... or 48v otherwise those LEDs would have been toasted. In reality, I am guessing that the stock bulbs are mismatched on the voltage front - maybe intentionally, to give a more valve like glow as opposed to a bright light? May be worth getting a meter in there next time somebody has one open so we know what the actual voltage being delivered is. 1 Quote Link to comment Share on other sites More sharing options...
GreeneKing Posted January 20, 2020 Author Share Posted January 20, 2020 The amp was faultless tonight. I love it. Just using one of my Accugroove Tri112L 8 ohm cabs and it copes with ease. Okay it's a heavy old lump but weight or size isn't an issue for me. I've mainly used 500 watt class D amps before but the Fafner seems to have more headroom. Quote Link to comment Share on other sites More sharing options...
Bassmumus Posted January 28, 2020 Share Posted January 28, 2020 Hi Can someone send me a link where can I order a direct replacement for the bulb? Mine is also blown. Quote Link to comment Share on other sites More sharing options...
GreeneKing Posted February 2, 2020 Author Share Posted February 2, 2020 LED E10 bulbs/lamps These are rated 36v and work fine: https://www.ebay.co.uk/itm/E10-LED-Instrument-Screw-Light-Bulb-0-5W-6-3V-12V-24V-36V-220V-380V-9x24mm/401413860545?ssPageName=STRK%3AMEBIDX%3AIT&var=671045700741&_trksid=p2057872.m2749.l2649 This is rated 48v https://uk.rs-online.com/web/p/led-indicator-lamps/0206700/ I've got one but not tried it as the first ones are great. Peter 1 Quote Link to comment Share on other sites More sharing options...
Bassmumus Posted February 12, 2020 Share Posted February 12, 2020 Thank you. I ordered it. I hope it will be fine. Quote Link to comment Share on other sites More sharing options...
toskidus Posted July 31, 2023 Share Posted July 31, 2023 Hello, do the UK 48v led work alone or with a resistor or anyother stuff ? Tks a lot. Quote Link to comment Share on other sites More sharing options...
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