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Luckiestmanalive

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About Luckiestmanalive

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  1. I switched the crossovers between the cabinets, played my frequency sweep and found that the MIA tweeter has also switched cabinets so that narrows it down to the crossover board. So I've ordered replacement capacitors from Falcon Acoustics - all done for $60 airmail delivered. My Audio Physic Sparks are back from the Speaker Hospital so I'm no longer bothered about waiting. I'm back to listen to some music now! I will come back to this thread to provide an update on how the capacitor replacement goes.
  2. Thanks, guys. VA - thanks, yes, of course the 7uf capacitor is on the MF circuit. I could do a whole bunch of replacements and hope that fixed it but the freight times at the moment are iffy and I don't want to spend too much right now. mbz - I haven't ruled out a loose connection between the crossover board and the connector socket. I can't see any loose connections and I've refreshed the solder on the components that matter. Also, the multimeter reads a connection (0.4-0.6 amps) between components that connect the HF+ and HF- on both crossover boards. I don't want to experiment with my expensive amp (Plinius 9200) in case I blow it up. This project isn't worth that risk!
  3. Reading over some old threads it looks like I should replace the offending 7uf capacitor and Zaphod has recommended a film capacitor as a replacement that should be an improvement. I've found a few 7uf film capacitors that fit the bill and settled on a kemet 7uf 650V +/-5% tolerance radial box capacitor: https://au.element14.com/kemet/c4aqcbu4700a1yj/cap-7-f-650v-5-pp-radial/dp/2846428 It looks like it will fit the existing space almost perfectly albeit a little taller than before (double the height at 28mm). I will order 2 and replace the same capacitor on the other board at the same time (after doing an AB test first, of course). Would anyone suggest something better?
  4. OK. So I went mad with the multimeter and soldering iron on the offending crossover board. I refreshed the solder at points where I wasn't getting a good reading from the multimeter. Then I checked the readings between soldering points and the connection points where they were on the same trace. I was getting 0.4 ohms everywhere I tested. Then I tested the + and - connections at the bottom of the board. On the good board, I was getting no reading from any of them. On the other board, I was getting no reading from all but the MF connection. It was reading 3.4 ohms. This corresponds to the reading I got across the capacitor on the bottom right of the pic above. I got no reading from the corresponding capacitor on the good board. Have I found the problem or just another one? I mean, the problem I have located seems to stem from the MF circuit when it is the HF circuit that is somehow not moving the tweeter? The HF problem could still reside in a lack of connection between the PCB and the socket it slots into.
  5. Thanks, guys. I definitely will replace parts if I have to but would like to track down the fault with the present circuit first, in case it is just a loose connection. I've tested the connection to the tweeter at the HF+ and HF- connections just below where the wires go into the slot for the crossover board. The resistance is ~6.8 ohms and I get the same reading on the other side.
  6. Here is a pic of the offending crossover board and connection slot.
  7. Apologies in advance if I am asking stupid questions but I'm not experienced in circuit troubleshooting. I have a pair of Kef Concertos brought into action because my Audio Physic Sparks are receiving a little attention at the Speaker Hospital. I have noticed there is one tweeter MIA when I play music. The Concerto has an exposed board with the Crossover on it that slots into a connection slot, which is prone to being a bit hit and miss connection-wise. Also, my Concertos have the original board and components on it so there is always a chance of capacitor failure (though there is no outward sign of that). I have compared the resistance across all the components on the crossover board on both speakers. There are no open circuits and they measure the same resistance after giving the traces and solder points a clean with IPA. After taking out both crossover boards, I checked the HF connections in the crossover connection slot with my multimeter and again it looks like there is a closed circuit on the meter and the tweeter makes crackling noises when I do it. So I cleaned the connections in the slot, jimmied the HF connectors out a little to make sure they touch the crossover board, then slid the board back into place and tried again. But still no music from the tweeter. Bugger. Does the crackle from the tweeter when I test the connection in the crossover connection slot show there is no problem with tweeter and it must be on the crossover board? And if so, then how come I cannot find an open circuit in the crossover board? Do you think it is safe to switch the crossover boards and test again? Or will this risk damaging the other tweeter? Lucky I have plenty of time while we are in semi lock down to do this sort of thing or I'd have given up ages ago!
  8. Mate - you were underrepresenting the amp's capability. Ten KT88s will get you 250W - if you have the KT150s then you get 400W, according to 6moons!
  9. As you say, if you can find a collector focussed on this brand and model then you might get many hundreds and up to $1,000 or even more. However, the more realistic market is people just looking for a good 3 head deck who seem willing to pay a few hundred if the deck is in good cosmetic and working order, maybe less if it has been stored and unused for a long time...
  10. So after further testing I've found only one C90 tape in my meagre collection won't play and it happens to be Pet Shop Boys Discography, which is an XDR tape. Some of these tapes are known to develop problems in playback and some people suggest lubricating the tape to resurrect them. XDR tapes are supposed to be better quality soundwise than normal tapes so I may try the lubrication trick. If I do I will report back. The good news is that this means there is now nothing wrong with my Walkman, mechanically! I am now on the hunt for a DC power supply for my Walkman but I'm struggling to find one that fits the bill: - 230V AC with AU plug into 3vdc 300mA output into a 5.5 x 2.1mm center negative plug I'd appreciate it if anyone that can point me to the right place. I've tried Amazon and Ebay and even if I find the right output it is always center positive. I guess I could rewire but I would prefer to have a device that is marked correctly. I've also ordered my first brand new 2019 release on cassette to enjoy and test flutter - Ian Brown's Ripples album.
  11. After a lot of googling (big ups to all those people sharing their knowledge) and trying out stuff I've come to appreciate just how hard it is to get a tape cassette to sound good! Here is what I've learned so far about the importance of the tape grip and path to get good sound. The pinch roller and capstan are very important to get even tape movement over the head. If the grip is uneven then you get slippage and even a slight amount of slippage contributes to flutter. The roller needs to be clean of tape residue, pliable and even, without cracks or dents. You can clean the roller effectively with isopropyl alcohol and a cotton bud. Repeat the cleaning process (allowing time to dry between sessions) a few times and stop when the cotton bud is only picking up black and not brown material. The capstan also needs to be clean but not polished and smooth. Again, a cotton bud damp with isopropyl alcohol is fine for the cleaning job. To roughen up a smooth capstan, you can cut a small ribbon of 150 grit sandpaper about 30-40mm in length of 8-10mm width. Make a loop with the grit inside and pinch it with your forefinger and thumb. Loop it over the capstan and hit play so the capstan rotates against your loop of sandpaper. You might want/need to take the cassette door off to get better access for this job. I was silly enough to accidentally tighten the tape path screw before I knew what I was doing and this guide needs to be aligned with the tape path guide on the head to ensure the tape has a smooth and straight path over the head and onto the spool. To see how evenly the tape is going through your transport you can purchase a mirror cassette but you might already have a tape cassette with a transparent plastic cover which is adequate. I have one and I can see the tape's journey very clearly with the cassette door off and a light shining on it. This has helped me tweak the tape path screw to ensure there is no discernible flex of the tape before or over this guide. These relatively simple tips have made a discernible improvement to the sound of my tapes. However, I am still not satisfied it is as good as I can make it so I will report back if I make any further improvements. Then there is the problem that the machine just won't pull any tape longer than a C60. More research and investigation is needed...
  12. Update: I've reduced the flutter with a few repeat sessions cleaning all the brown tape residue off the pinch roller with a cue tip and some rubbing alcohol. It looked like it hadn't been cleaned since it was new! I've cleaned it until there is no hint of brown residue on a cue tip. There is no longer any shinyness and the roller still looks pliable and without any sign of dents or cracks. It is also getting better by using it. My 9 year old daughter loves it and we listen to a tape while eating breakfast together (there are two headphone jacks). With regular use the FF is dependable now (it doesn't cause the weird several seconds of playback once you hit stop) and rewind is also working more often than not. All in all, I'm pretty pleased with where I'm at so far.
  13. Thanks, guys. I'll see what model makers say and give the Sharpie a go. Its nice to see I'm not posting to a void!
  14. Being a long time owner of one of these, this is a great price for what you get. The DAC inside these is very musical and it has digital outputs (optical and coax) if you prefer. The Apollo may be the last CD player I will own and that is OK with me. GLWTS!
  15. The replacement screws for the ones that were missing arrived (I needed M1.4 x 2mm, 2.5mm and 3.5mm panhead screws in black) and they fit perfectly and look original so I'm chuffed. Here is the fleabay ad I sourced them from: https://www.ebay.com.au/itm/M1-4-Micro-Phillips-Pan-Head-Machine-Screws-2-8mm-Black-Oxide-Steel-GB819-Bx7/362751538419?ssPageName=STRK%3AMEBIDX%3AIT&var=631909341633&_trksid=p2057872.m2749.l2649 Also, here is the fleabay ad I sourced the 1mm rubber belt (should be 44 x 0.9mm but a 1mm one works fine): https://www.ebay.com.au/itm/30PCS-Cassette-Tape-Machine-Belts-Rubber-for-Recorders-Walkman-CD-DVD-Drive-AU/283603670977?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649 Now to replace the clear perspex window... looks like I will have to have one made off my cracked template. Any recommendations for perspex manufacturers?
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