Behringer SL2442FX-PRO > Trouble shooting Main Outputs....

[Jazz P Bass]

I believe that Audiobrad's post indicated that you remove the FX board & run the unit.

If the unit runs good without the FX board, then the board is bad or the 5 volt supply is weak.

[renz]

jazz and adiobrad thanks for help my problem fx display now is good. the main problem 5 volt supply is loss coming from socket dpxm remove and clean socket and install im observe my mixer sl2442fx 5 hours.is good

[audiobrad]

[renz]

audiobrad and jazz im come back again sorry for disturbed one problem my mixer power on mixer led meter always on ic 44, 39,45,51 already replace ic 53 not yet replace

[renz]

audiobrad how are you ic 53 im replace led meter left channel working but right led channel no working not fuctions no idia sulotion any body help..

[mr.xang]

Hi y'all. I own an SX2442FX & the older model SL2442FX, both bought from Guitar Center (GC) stores used gear postings online... for +/- $250 each. Ever since I got a genuine German new MX802A little mixer in '98, I've been sold on Uli Behringer's stuff. Next was a new MX1804X in '02, that with so much use, abuse & finally having no other recourse but to use it for parts in '19 (some drunk dropped a whole glass of red wine & messed up ch. 1 & 2 faders). Found a working but a little bit scratched MX1804A, again at GC & just swapped the motherboard (MB) of the newer MXX1804A to older one. Now I have parts for the SX2442FX, that had a couple of failing EQ slider, that it looked like something heavy was... again; dropped on it before I got it. Like most cheaper mixers, their channels are bused in parallel to each other & not individually summed up like say; an older Soundcraft, SSL or a Neve. By the way. Rupert just passed away this last Feb. 12th. Happy trails!, you pioneering pro-audio God !. Back at it, took a good Alps fader from the "wined up" MX1804A; then soldered to the older SX2442FX, that had issues with ch. 16 & messing up the main bus symmetrical stereo output levels. Replacing surface mount IC's, a tiny Op Amp ?, yeah right !. Maybe with a micro-surgery robotic arm/microscope & a micro desoldering iron... if it exist. Believe me, tried & never worked. Just desoldering those Alps, or whatever brand fader tabs from the MB with a Soldaput, wick & a desoldering iron; it is a delicate operation. You use too much heat, keep the iron too long on the tab; the heat gets transferred to the fader's carbon resistance strip &... there you go. A bad fader now. Next... suggestion.

[mr.xang]

Like in PC's, severs or laptops; dust is quite a problem. Add humidity & you have all the ingredients to mess up MB's tiny components & their related interconnections. In the case of faders, if not being soaked with high alcohol content Malbec; or the fader's tiny contacts with the carbon stripe getting bent, that stripe with time will oxidize. Lot faster when constant ambient air is very humid. The 1st thing I do when I get a used Behringer mixers, is to take it apart & clean the heck out of those faders. For the longest I used those smallish & expensive cans of Deoxit. Flattening the shaft of Q-Tips so it will fit, soaking it with "the miracle pot cleaner" or directly spraying it to the fader slot. Then carefully wiping the carbon strip on the channel fader or the EQ slider pot, making sure that the Q-Tip's cotton fibers don't get tangled with the faders delicate cooper contacts. A couple of years ago, I discovered that I got the same "pot rejuvenation" results; using instead of Deoxit, a much cheaper & much bigger cans of CRC QD Contact Cleaner. Then finishing up the "rejuvenation" with CRC's 2-26, Multi-Purpose Precision Lubricant. They can be found online & better yet, at the electrical section of either Home Depot or Lowe's. As mentioned, dust is quite a hazard to all electronic devices & even as mixers are not usually exposed to dust; since now with the CRC's abundant "miracle liquid" cans, I also spray a bunch of it to the MB & brush up all the surface mount components with a 1" nylon paint brush. Thus making sure all the connections between parts are free of crud. Now with a ton of "miracle juice" at my disposal, I also spray the rotary pots & those seemingly delicate push buttons; like the ones for the PFL/Solo or the Mute switch. Soaking the hell out of then too, I also spray the connectors of the ribbon wires. Like those that connect power to the MB, the ones for the FX board or the ones that interconnect channel sections (the SX/SL 2442FX have 3 of 8 ch. each module). Like those bought used SX/SL242FX & the newer MX1804X, I'm almost sure that they got "rid off" for these issues that the previous owners didn't know could be fixed... with a "little creative maintenance". That is my suggestion. 1st clean the heck out of those components mentioned. Then look for a bad phono plug. Some of them, like the ones on active p/u guitars; have a switch function built into them. If a tab, arm or contact to ground gets bent; that function is now inoperative & could very well be the cause of your channel malfunction. I've seen this happen to TRS phono connectors, one time not allowing to be a send/return port. If all that is not the cause... then an MB cap, diode, resistor or any surface mount part just went kaput. That is too bad & like my Malbec soaked MX1804A, Guitar Center's Behringer "salvage yard" was my only real effective & affordable option. Next... Behringer ah !!!.

[mr.xang]

Dad was a pioneer in telecom & broadcast engineering, in a small south Central American country. He took me since childhood, to be his assistant whenever the job was not too dangerous or took days to complete. So I grew up around telephone exchanges, radio or TV studios/stations & more importantly; the shop at home & the other one he had for his apprentices. He & those shops, were the service bureau or the country's official repair center for stuff like Honeywell & Bell & Howell projectors. Grundig radios, Middland or Pearce Simpson marine radios, Heathkit & even McIntosh amps that his audiophile friends ask him to repair. As you can see, I know a thing or two about electronic stuff, specially when it has to do with broadcast equipment. Definitely has to be high quality & very, very reliable. But sometimes cheaper stuff will fit just fine. Like the National, before it became National-Panasonic & then Panasonic early 60's turntables; that replaced the 4, 5, 6 times more expensive 50's Thorens on the radio station. Still have one of those & it cost me a pretty Swiss Franc penny, to replace the belt & capstan. As a musician & electronics obsessed maven, I truly admire Uli Behringer's brand. Among them are the incredible 2 DEQ-2496, the SX/SL2496FX. The spare parts MX1804A & the working one. The '98 MX802A. A pair of RX1202 I use on the "amateur home FM station" (search Blonder-Tongue ZFMSM CATV FM modulator). Few 15 & 32 band EQ's & other bunch of Behringer pieces. I also have used XR16 Air & X32 digital mixers & the newest, a Flow 8 that replaces the classic & still flawless MX802A; that I used as guitar, bass, keyboard or e-drums pre-amp. Speaking of "pre's". In my opinion, earlier Behringer mixers like the MX802A & the MX1804A; have better sounding pre's & to some extent, next gen SL2442FX preamps. That is because of what Uli did to the transistor's bias of those Op Amps (8540?). That Op Amp was used primarily in telecom for his very stable high frequency switching capabilities. Somehow he found a way to cheaply bias it for use in analog audio apps & that fast frequency ability got translated to high audio upper audio spectrum definition & low distortion. That Op Amp low end definition... ah, that's for another day. I have mirror test & compared similar age Mackie board to the MX1804A & the difference is like comparing old school classic Turkish Zildjian & Paiste Turkish Cymbals. The Zildjians will have that bright sounding sizzle, and the Paiste will have a "darker" less bright sound. It is a question of taste, but I prefer the brighter sound. Now, the SX2442FX & all newer Xenyx boards; use a different pre-amp design & is not as "sizzling" as the SL2442FX. Still sounds good but... . As for digital boards, call me old fashioned; but I compare the difference between analog & digital mixers, like the discussion between vinyl analogue records & CD's. To me digital mixers sound a bit stale. Just as some CD's sound too compressed & lacking character, compared to say... Supertramp's Breakfast in America totally analog recording. Maybe I have to really sit down & "lock ears" to higher end mixers like an Allen & Heath C, SQ series. Digico, Midas or Avid mixers; to change the opinion of my opinionated ears & perhaps antiquated ears. Perhaps too when future 32 or 48/192 khz sampling rates become a reality... so hurry up AKM !. One thing for sure, I really hate how current digital Yamaha, QSC, Mackie & Presonus sound. The X32, ah... for the studio & mostly for mixdown or mastering. You see, I use a cheap decent pre for vocals, FMR... can't remember the model. Art Pro something or Behringer MIC2200. Then open up the sound going with a digital mixer set up & to the PC thru a Focusrite Claret 18/8 USB (can't remember the model, but is an 18 in & 8 out). For live, the SX/SX2442FX, other Behringer, Soundcraft & a late 70's MXR board. Then main & side monitor speaker management out thru the Air XR16. With the SX/SL2442FX Subs, not used FX 1 & 2 channels & dual monitor outs, there's plenty flexibility for instrument & vocal monitoring, since the FX are now generated with the digital console. I believe there's great value or cost effectiveness by using Uli's gear. Yeah, they have a "sweet spot" sometimes hard to find. They break, hard to fix & getting any parts or info from Behringer is a frustrating odyssey. But if you use a Tripp-Lite power conditioners like the LS606M or the LC1800 & up; at least your Behringer & all your gear will be operating with clean optimal 120v/60hz juice. All electrical & electronics starts with... there you go. Clean, stable & correct power will certainly minimize any spurious or dirty voltages that can mess your electronics internal components. If they break, they are so cheap... . Tube versus transistor, versus digital amps... that's for another day too. For another "shop talk" day too, I'm also a cheap ass Microphone Obsessive Compulsive geek (MOC). Love my Rode NT-1 series mikes. AKG D-5's. E/V neodymium mikes, CAD & specially the hard to find early 2000's D95 condenser &... wow !, check them out. Neewer's NW-040. Only 20 bucks, but don't drop them. The capsule base comes loose & it can ruin it. I have a preventive fix for that too but... bye for now y'all.

[mr.xang]

Oh, oh oh. You're right Jazz P Bass & Audiobrat. Tried to repair a friends powered Behringer mixer, that when you send/return to the FX bus; it made this weird noises. Definitely a bad FX module. At that time Compass... Sweetwater?, were carrying Behringer boards & asked if they had an FX sub component PC board for that particular mixer; no luck. Called Behringer's Nevada official service center & no luck either. Way too old & such a particular FX module; no longer in stock... or all of them sold out?. So she now is using it without the FX board & for FX she patches thru an equally old Lexicon FX rack unit. One of my bought used RX1202 FX did something similar to... the right channel?. But somehow I just cleaned the whole motherboard & the area where the soldered in FX chip is &... , problem solved. I do recommend that 1st thing you do to troubleshot any electronic piece of semi-functional electronic gear, is to clean pots, switches, PC bords... everything; with CRC's QD Contact Cleaner & for pots & switches, lubricate them with CRC's 2-26 Multi-Purpose Precision Lubricant. Lots cheaper & lots more bigger can than Deoxit's expensive & smallish spray can. That way you eliminate those mechanical parts as the source of you problem. CRC products can be found at Home Depot & Lowe's electrical department.

[Helmholtz]

Hi, mr.xang,
I'm sure you have some useful experience and knowledge to contribute. But this is a 6 year (actually 11 year) old thread, so...