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Salutations great people of the Steronet! I've run into an issue repairing an L-308 Luxman and require assistance. Some monster has replaced all of the transistors on the power board with the same BC type transistor. Unfortunately the power board is an updated PB-731A version and I can only find the schematic for the original PB-731. Does anyone have the appropriate schematic? Or a 308 with said 731A power board that they can provide me with what Q701-705 should be? Any and all assistance greatfully received. Many thanks and happy listening!

So I recently opened up my dad's old Sansui AU-101, it was making horrible scratchy noises so I used some DeoxIT to clean up all the pots and inputs and that seemed to clean all the noise up. Only issue I'm having now is that the right channel is far quieter than the left channel. And when I say much quieter I mean when I have the balance knob set all the way to the left, I can turn the volume up to 3 or 4 to be able to comfortably hear it, but if I turn the balance knob all the way to the right, I need to put the volume past 8 for it to be able to get to a listenable level. I've tried with both speakers and headphones, and both have the same issue. Another thing to note is that before this happened, both outputs were equal, with the only exception being that the right channel was not very full sounding (not as much bass or treble) but they were both as quiet as the right channel is now, so I had to put the volume knob past 7 to be able to comfortable hear anything. The thing that got the left channel to go back up is when I played around with the Source/Playback switch, I kept switching it back and forth to clean it up, and now it's in the current state of the left channel being loud enough for my liking, but the right channel being extremely quiet. What can I do to either diagnose or fix this? Thank you

Hi all, I own an old Musical Fidelity A100-X. I haven’t had it from new but I do have the original receipt and it was purchased new in 1990. In 2009 (a couple of years after I bought it) it failed and I had it repaired. Not sure what the guy did but the invoice noted “rebuild”. Anyway, fast forward 14 years and there’s a wee bit of noise in the left channel and some crackle in the volume and selector so I’m thinking perhaps some preventative maintenance seeing as these amps run hot and are notorious for cooking themselves. any recommendations on where to take it in Melbourne? Should I go for a full recapping or is that overkill seeing as it hasn’t failed? Anyone out there got experience with this?

Hi everyone, it's been a while since I have posted, however I recently purchased a marantz cd5005 cd for $50 in silver which had a laser pick up issue, it wasn't reading any discs, but I purchased it mainly because if this player could be repaired, it would be one of the best bargains for me. Note: I didn't take pictures of everything that I did, but hopefully you get what I did. Dismantling the player was the player and disc mechanism was the easy part. Getting the new laser mech ready for installation. As per instructions of most Sanyo laser mechanisms that I know of, the two short circuit contact points outlined in the picture above, out of the box are generally soldered together, once the assembly was done I made sure that the 16 pin ribbon cable was connected first before desoldering the short circuit contact so that it looks like the picture above where you can see two contact points. Then I just assembled everything back together ready for testing. And it's all working well, I used headphones to test the sound and is all working well with no need for further adjustment on the little pot for the laser. All put back together ready to play. The main problem was that the original laser mech had laser had gone off which I later found out was due a shredded bit of the circuit on the side of the laser mech which tells me that the player had been opened up before. But now that the player is fixed, it will be in my system for many years to come.

I know there are many stories about LCD3 drivers giving up. Mine was purchased in Europe in 2014, started having trouble with the left driver intermittently and it finally gave up couple of months ago. I reached out Audeze service, they indicated that its out of service (which I knew already) and that it would cost a whopping 598 USD + shipping to US and back. I prefer my HD800 and have not used LCDs that much, funny that HD800s are still going strong barring a cable tear and headband change and LCDs died on me. Has anyone had similar issue? Anyone got any idea if this can be repaired locally?

Hi Stereonetters, Today I purchased for NZD$1 (deemed as E-Waste) two Tascam 112R MK II Cassette Decks - I am looking for someone in NZ that can assess and repair at least one of them. One of decks powers up but when I play a tape it goes into Record Pause Mode. Neither Play, FF or RW is functioning. I contacted Fred at Retrotronics in Auckland but he does not repair he prefers to buy, restore and sell his own equipment which is understandable. I am based in Hamilton New Zealand and the repairer could use parts from one to the other or repair both... after paying out $1 I'm happy to throw some coin into this job could even give one of the decks to the repairer if they want to have one for themselves...as long as I get my one up and going. Parts available from https://tascamninja.com Let me know if you a guy or gal up for the job, cheers William.

Hi all, I'm new here as of yesterday. I pulled a Nagra IV SJ reel to reel tape player from a skip bin nearly two years ago. Does anyone know of anyone in Australia or the best place to get things checked out or to just get replacement parts for some of the perished follower wheels etc? I talked with the guys that owned it and as far as they knew it was in good order, they were just instructed to bin all gear that had not been used in recent times due to downsizing of the office. I also picked up an old B&K meter which is of interest to me (acoustic engineer) from the bin. I'd like to get it running and try it out.

Dear fellow members, My Marantz AV7701 started to have a mind of its own and now is continuously restarting on/off. There is a YouTube clip of another with the same issue so it seems to be a common problem. Comments below on YouTube from another poster suggested it is the PSU. Here is the clip (it's not me btw :-) ): The question I would like to ask, it is worth spending to repair or just save and spend on top for a new unit? I mean at least I would assume the repair may be around the $400 mark .. Even if the repair is good, usually warranties from the repair mob is not very long. As we all know that a replacement Prepro will not be cheap. 4K passthrough is not that important (although it does supports it however 4K@30p) I am in Melbourne and I believe JLS electronics is pretty good. Has anyone been in this dilemma? What would you advise. Thanks for your time. Cheers

Hi guys, I've got an old Sansui AU5900 thats in lovely condition except the relay has died on me i.e. no 'click' when you turn the amp on. Manually toggling the relay (with a hell of a lot of insulation) results in glorious glorious sound so I'm planning to unsolder and replace it. I'm not sure where to find a replacement though. The relay is marked as an Omron Type MY02 and also has -0-Y23 printed on it's plastic cover. Since google has been of very limited assistance, can anyone point me in the direction of a replacement? Cheers, Tim

Hi, Does anybody know somewhere that does repairs on super tweeters, the brand is Grant. Any assistance would be helpful. Thanks in advance. JJ

Well, I learnt an important lesson a couple of nights ago. Don’t use halogen desk lamps to light your metal Supex cartridge trying to take photos of the stylus ...idjiot At some point I noticed my Supex 901 Super was getting quite hot. I took a couple more shots and then re-mounted the cartridge to TT thinking I’ll just listen to one more Lp before bed. Alas, I’d lost the left channel. I desperately checked all connections and even swapped headshells but no luck. Devastated. Nothing worse than ruining something you love with stupidity! So.... I’m guessing the heat has fused or severed/popped the left coil? Can anyone help to let me know if I’m on the right track, and can it possibly be repaired??? There was a tiny volume of music coming from the left speaker but only just. I love that cartridge and they’re not easy to come by at decent cost so I’m hoping I can get her up and running again.

Hey everyone, thought I would share some pictures of my BAT VK500 before I send it away to the United States for repair I emailed Balanced Audio Technology a couple of months to see if they had any idea about what was causing the crackle/popping sound coming from the right channel of the VK500. I expected to get some generic email, but to my surprise the owner of the company Victor Khomenko responded directly to my email to see if he could provide some assistance. Since my initial email to Victor he has really been a great help and has replied promptly to all my inquiries. BAT's customer support really is a testament to how good of a company Balanced Audio Technology really is. They build good gear and offer great support. Here's a Stereophile interview with Victor from a few years back: https://www.stereophile.com/interviews/767/index.html I'm not a technician but I managed to remove both Channel's from the amplifier with little trouble. Anyways here are the pics and will hopefully have it shipped by the end of the week.

My apologies if this isn't the right place for this question. Yesterday I turned on my Xindak monoblock and it shat itself. Smoke, all of that good stuff. Was wondering if anyone could recommend someone good to take it to for repair? Cheers!

Hi, my Pioneer LX608 plasma no longer seems to be able to get to standby mode, let alone turn on the screen. Could this be a capacitor problem? Any good recommendations for repair in Melbourne east? The tv is out of warranty, and since Pioneer closed shop I've no idea where to look. Cheers.

Hi All, Long time lurker, recluse poster !!! I have a 60" Samsung LED TV (UA60ES8000) . When we moved homes I noticed two light spots appear on the screen. I can't recall them being there prior to our move however we had the TV in another room and it wasn't watched as much as it is now so the cause of the problem is unknown. The light spots only appear on light colour images... e.g., they are visible when a white image is displayed yet not when a black image is displayed. They are not perfect circles which makes me this the issue isn't pixel related. Things I've done to fix it to date include 1. Suspecting it is pressure related I removed the back of the TV to see if any screws from boards were placing pressure on the rear of the LED screen, no such luck 2. I've followed a few guides on here which suggest turning the TV off and applying a firm wiping motion from the centre of the screen to the outer edge, this hasn't helped either. I've attached photo's below, does anyone have ideas about what could be causing it most importantly how to fix it ? I've called 1 Samsung repairer and they seem all to happy to replace the screen rather than try fix it, cost is about $1400 for a new panel ! My questions.... Can I fix myself ? can someone else fix ? does it require a new Panel ? Driving me nuts when watching sport (which I do a lot !!) as it the green of the grass is terrible. Thanks in advance. Dylan

Item: NAD T973 (Broken) Location: Emerald VIC Price: Free (Donation to SNA is much preferred) Item Condition: Broken Reason for selling: No use to me, funding towards SNA Payment Method: Pickup - Cash, Paypal, COD Only Extra Info: No pictures Hi I have an old NAD T973 7 channel power amplifier sitting in it's box that I have no meaning for. 5 years back the amp created a fault in one of the 7 channels and would go into protection mode. Since it was an insurance job 1 unsuccessful repair has been made after which they decided to pay out. The amp has been sitting in it's box since then and was forgotten about until our last move. I decided to turn it on and perhaps have the faulty channel removed and turned into a 6 channel amp, but as soon as I did this, silver sparks and a foul smell occurred from the area where the capacitors are located. Boxed it up again and moved it into the garage. For anyone who is interested this unit is free to be picked up, but the more generous person willing to donate to SNA will be the preferred choice. Shipping will have to be arranged by you, but can become a bit costly due to the size and weight of the box. I am pretty flexible with my time, so I don't foresee any drama's there. Box dimensions are 72cmx72cmx40cm and roughly 35kg. (Unit itself is 31kg)

I have rotel rb-981 power amplifier..However it powers up and protection light goes off.

Hi All, I've just pulled a few bits and pieces out of storage for a play, one of which was an old Sansui AU3900 which is still in lovely cosmetic condition. I plugged her in last night and it powers up (I can hear the usual relay clicks etc) but all I can get out of it are pops and cracks. The cracks are very loud and don't seem to be influenced at all by the volume control. I popped the lid for a quick inspection but everything looks OK visually as well as minimal dust etc. I can only spot one main fuse at the rear which is obviously intact as she powers on. I'm thinking it's probably dead and beyond my skill level to repair but I'm reluctant to give up so easily. Any ideas? Cheers, Tim

Hello Any comments on the best place to get speaker drivers re-cone / repaired ? I am in VIC. I have older Duntech Princess. I found a place online that has been very helpful in emails, although i just noticed they seem to have some bad reviews online, this has me a little concerned. Any comments or advice would be much appreciated. Regards Rob

Item: JFJ Easy Pro Plus Disk Resurfacer/Polisher - Brand New Location: Mascot - Sydney Price: Looking for $150, this system cost me almost $300 shipped from US. Item Condition: 10/10 Brand New Reason for selling: Not Required Payment Method: Pickup - Cash, Paypal, COD. Can ship anywhere in Australia for small fee. Extra Info: Brand new and purchased to fix some of CDs prior to ripping to FLAC for Digital System. Shipping on this took forever and ended up getting ripping company to polish the damaged discs with similar machine. Its the genuine 220v factory version with extra supplies - good for 200 repairs. New JFJ Easy Pro Plus CD/DVD Repair Machine 220 Volt with Extra Supply Kit JFJ Easy Pro: Designed for businesses and individuals who will be doing less than 50 repairs per week. The sanding feature enables the Easy Pro to remove deep scratches, gouges, and even the ring of death from Xbox 360 discs. Easy Pro is capable to do more than 50 repairs per week; however, it has a DC motor with a thermal protector that will shut it down during 20-30 minutes of constant use to prevent overheating. When it comes to repair, it does not matter how deep, or bad the scratches are, JFJ is able to repair it, or your money back! 30-day money back guarantee, and 1-year warranty. Extended 1-year and 5-year warranty available for purchase from the manufacturer. Use as a one-step machine for skipping, fingerprints or light scratches, or as a multi-step machine for deep scratches and gouges. Lightweight, silent motor, and safe compounds make the CD+ – or DVD+ – look brand new every time. No water needed! You do not have to deal with filter changes, water pumps, water hoses, or dirty water! Easy to operate Unlike some other products, which have a high maintenance, the Easy Pro’s maintenance is very low. Works on all compact disc formats: Music CD, CD-Rom, DVDs, Sony Playstation, Playstation 2, Playstation 3, Playstation 4, X-BOX, X-box 360, XBOX ONE, Blu-ray, Wii, GameCube, CD-R, DVD-R, and HD DVD. Complete Easy Pro System Includes Repair Machine basic design with screw nut, (1 pcs) Easy Pro buffing pads – White, (2 pcs) 4oz. Easy Pro Solution #1 – Blue, (1 pcs) 4oz. Easy Pro Solution #2 – White, (1 pc) Disc plate, (1 pc) Easy Pro black sanding pads, (2 pcs) Coarse sand Paper – Black, (3 pcs) Soft sand paper – Gray, (3 pcs) Anti-static spray, (1 pc) Cleaning cloth, (3 pcs) Extra supply kit includes the following: Easy Pro™ Buffing Pads, (2pcs) Easy Pro™ Solution #1 (blue) 4 oz, (1) Easy Pro™ Solution #2 (white) 4 oz, (1) Anti-Static Spay 1 oz, (1) Soft Sandpaper, (3pcs) Coarse Sandpaper, (3pcs) Cleaning Cloths, (3pcs) Total supplies included with machine are enough for about 200 repairs.

Hi everyone, Apologies if this is the wrong place to ask, I'm new here, and hope someone can help. I've got an older Denon AVC-A1 which has pregnant capacitors on the power supply. They are marked ELNA For Audio 15000uF 73V, however I can't find any reference to this spec capacitor anywhere. I'm just going to replace them with a bigger capacitor, or one with a higher voltage rating, whichever is cheapest, but my question is, do I really need an "audio" spec capacitor for this stage, I would have assumed if anything, ripple current would have been priority? Also, there are a HECK of a lot of caps around rated for 63V, am I ever going to see voltage that high in that section of my amp, or can I get away with lower rated caps? TIA EDIT: I shouldn't have trusted what I saw, according to service manuals they should be 71V rated and marked DENON.... these are likely fakes. Oh well no better time to replace them. Probably don't care so much about the previous questions considering they are readily available now.... Cheers

Hi, For some reason I started looking into older and vintage amplifiers because I am starting to like the look of it. Either I have become of vintage age, or it is the age where vintage is cool. I do hope it is the latter. If they age just like me, than I might expect a few quirks and a bit of maintenance to buff up the aged interior. What things should I take into account, when buying an older amp, or other equipment? An internet search came up with a couple of things. - Bias/DC adjustment. Can this be done with any amp? - Checking and replacing capacitors. The lifespan of these things seem to vary from 10 - 30 years. Would you replace all of them? - Resolder dry joints. This seems to differ with how hot the unit runs and if it frequently has been turned on and off. Would you resolder every individual dry joint or just in some particular areas? There are probably even more things that I haven't found out yet and looking at these, is it really worth the trouble? Would a similar priced modern amp being able to catch up with an older or vintage high end unit? I wouldn't mind trying some stuff, but how much cash would I need to keep at hand, to make this an enjoying experience?

Hey folks, I'm looking for some help with troubleshooting my Technics SE-A900S power amplifier which distorts in the right channel at higher volumes only. Sorry about the long post by the way! I've already spent some time looking for the issue and so have plenty of context, which I'll try and make as succinct as possible. Troubleshooting notes and context: The distortion is in the right channel only, in both speakers A and B. Tested with two different sets of speakers and have also tried switching the speakers around. Distortion is always on the right channel - ruling out speaker issues. I don't hear any distortion on headphones plugged into the headphones jack on the front of the amp at any volume. There is no distortion at low sound levels. It only kicks in at higher volumes and I was able to confirm this with a scope as well (More details in linked pictures below). There seems to be no distortion in the output if I remove the speakers at any volume levels (confirmed with a scope). Visual inspection of the circuit board shows no signs of damage, burns, faulty components like bulging capacitors etc. When I first opened the case, I noticed a weird plastic/metallic looking film stuck across a couple of the legs of the IC SVI3205B (which is the power amplifier IC). Removing this made no difference to the issue. Continuity test showed that this material isn't conductive. I'm assuming this was never a problem but thought I'd mentioned this anyways. (I know the film looks little like what might be used in electrolytic capacitors, but I have spent a fair bit of time hunting for any blown caps but I see none.) Scope output at various frequencies. I used an audio signal generator as source and then plugged my scope in parallel with a speaker to measure amplifier output. Source signal was always a sine wave at various different frequencies. 200Hz Right channel, distorted 200Hz Right channel, clean 800Hz Right channel, distorted 800Hz Right channel, clean 1.6KHz Right channel, distorted 1.6KHz Right channel, clean 3.2KHz Right channel, distorted 3.2KHz Right channel, clean 6KHz Right channel, distorted 6KHz Right channel, clean 12.8KHz Right channel, high volume distorted 12.8KHz Right channel at low volume, clean 12.8KHz Left channel, high volume clean It also seems like the signal starts distorting at lower volumes at lower frequencies and requires a lot more volume before it starts distorting at higher frequencies. [Circuit diagram of the amp from the service manual (I've tried to trace the Left and Right channel signal path in the circuit diagram using Yellow and Orange colours respectively) as context for the following notes.] I traced the distorted signal through the circuit and can see it all the way up to pin 16 of the preamp IC AN7062N, however, there is no distortion at pin 17. (This is located at the far left of the circuit diagram I linked above, not too for from the signal input posts) I've swapped out the transistors Q402 and Q452 with the equivalent transistors Q401 and Q451 on the left channel respectively and the distortion remains in the right channel. I have also spent a bit of time testing most electrolytic capacitors in-circuit with an ESR meter but don't have much to report here. I've also re soldered some joints along the right channel, but definitely not the entire path... this was random and seemed like a waste of time. While asking for help elsewhere, I took pictures of the actual circuit board, linked below in case they are helpful. Circuit top shot (stitched, there is a fair bit of overlap so may look weird) Circuit top shot Preamp side of the circuit Shot of the MOSFET module Power amp module and the adjacent circuit Shot of some of the transistors across the L and R channels The main caps A shot of the bottom of the circuit board showing the traces (stitched, again there is a fair bit of overlap so may look weird) Circuit board bottom Would appreciate any help I can get in hunting down the root cause here. Thank you for your time and help

Hi, I just purchased a pair of Acoustic Research AR9LS tower speakers for a change from my JBL 4311Bs as I am predominantly using the latter for mixing at the moment. I guess I am used to the JBLs and their rather precise monitor sound, but I am a bit unsure as to whether the AR9LS are performing as well as they should be. When listening to more rock oriented music (John McLaughlin's Devotion) I lose quite a bit of cymbals and the brightness of the snare, I don't seem to be getting super big bass/lower-mids on some records either (on the lower-pitched percussion on Ali Farka Toure & Ry Cooder's Talking Timbuktu which hits pretty hard on other setups). But I must say that listening to acoustic guitar instrumentals (Bert Jansch/John Renbourn) there is still a pretty lively, bright sound with a good amount of detail. I am new to any kind of speaker repair. First thoughts is that maybe these need new caps. The cabinets are pretty worn and someone suggested that these were kept outside on a deck and that someone they know might have looked inside this exact pair and seen some corrosion--but this is pretty foreign to me. If anyone has any tips on what might be the problem, or what I can do to investigate further that would be much appreciated. Happy to have a go at any repairs necessary! Cheers T

Hi All, I'm having trouble with my Rotel slot load CD player (RCD1570) It's not pulling discs in properly, makes a little bit of noise and jerks/jolts them a bit. It doesn't happen all the time, but mostly when inserting rather than ejecting a disc. any ideas??