This Bose 901 Series I Active Equalizer came to me from North Carolina, where it had been stored in original packaging for many years. Unfortunately even with careful storage the equalizer wasn’t in running condition and it looks like the years hadn’t been great to it.
This one has an engraving on the back from a previous owner. These equalizers have been around a long time and many have had several owners.
The plating had experienced pretty serious corrosion. The board itself wasn’t in much better shape – corrosion was growing up the component legs through the board and was degrading the copper traces and the board material itself.
This one was tough because the traces were damaged around many pads and required very careful soldering to make solid connections.
The original transistors all had very bad corrosion on their legs so they all were replaced. The 22 mH inductors in the low frequency circuit also were replaced with new precision models as the ultrafine wire had failed from internal corrosion.
The owner of this equalizer requested I install some pigtail jacks to help them connect thicker interconnect cables to their equalizer. The narrow pitch of the RCA jacks from the early 1970s isn’t wide enough to accommodate today’s highest quality interconnects and these are a great solution to adapt to the last few inches of cable run. It’s also a fully reversible modification.
This equalizer got an upgrade to the output capacitors to audiophile-grade film capacitors. These really bring out the fine detail in the music in a way that’s just not possible with the original electrolytic capacitors, and this is a great way to bring some of the advances in materials science over the last 45 years to these classic speakers.
This equalizer sounded great in testing and really delivered on the wide, powerful sound the Bose 901 speakers are known for!
These Active Equalizers are key to the system’s performance and it’s important to have them working in top condition. If you need yours repaired, I can help.
I just had another Bose 901 Series I equalizer through the shop for the standard service. It didn’t have a visible serial number, but is definitely a very early production version. The Active Equalizer was revised once through the model’s production run, with serial numbers below about 10,000 being a substantially different PCB layout from the Second Production equalizer. I don’t run into these Early Production ones very often, and each one is a little bit different. Towards the end of the first production run, they started to appear with riveted jacks but this early version has screwed down jacks on the rear. It’s always interesting to see what variations there were before they standardized on the later design.
Bose 901 Active Equalizers, along with Bose 800, 402E and 802 controllers often need service these days, with more and more original units failing as they can now be over 45 years old. By replacing all of the leaking capacitors and resistors which have drifted from their nominal values, they can be restored to perform like when they were new!
The Series I Early Production boards have no solder mask and so no component labels on the top side. The circuit has some major differences to the circuit of the Series I Second Production equalizer, but they function the same. Double-checking is the way to go to here. In the Second Production equalizer, there are 2 large and 7 small filter capacitors plus the four output and feedback capacitors arranged on the top row towards the jacks in a line. The layout is more chaotic on this early board; the wiring to the switches also has quite a bit of slack in it.
The Early Production equalizer users 12 transistors, 2N3393, with 10 wired up as amplifiers and 2 wired up as Zener diodes, bypassed by 3.3 uF capacitors. I’ve replaced the 2 extra transistors with discrete Zener diodes and the original leaky package transistors with brand new TO-92s of the same number. In the case of this early version, the original transistor packages seem prone to failure, and I’ve never run into one without dead original 2N3393 so they’re all replaced immediately now. The second production version used 2N5088s, and realistically they’re interchangeable, but I stock both so each can be replaced with the original part number.
This one is in very good physical condition, it looks like it has been stored very well. The switches were a bit sticky, but a careful application of contact cleaner followed by working the switch cleaned it right up so it’s much improved.
Shining a light from beyind the board, it’s easy to see the traces on the back side. The new transistors pinouts are different from the original, so they mount differently in their sockets:
This equalizer received a complete reconditioning, and an upgrade to the output capacitors to audiophile-grade film capacitors – these really help bring out the fine details in the music that aren’t there with the electrolytic output capacitors. This is one major advantage of technology today – and simple upgrades like this at the time of service can bring some modern improvements to these classic speakers.
The Early Production equalizers take a bit more time to recondition because of the board layout, but they’re very enjoyable to work on. The PCB swings up with all the connections on one side, so nothing needs to be de-soldered from the panel to service the board, and the traces tend to be wide and easy to solder to. With these repairs, this equalizer is going to sound fantastic for years to come.
I’m happy to announce Rain City Audio can offer classic speaker refurbishment!
Classic speakers are always a delight to work on, and speakers have capacitors and other parts which require service, too. Over the years those components can fail and result in poor sound and even potential speaker damage.
In this case, the speakers on the bench are the Ohm Acoustics Model D. Ohm is more well-known for the Walsh speakers which produce an interesting omnidirectional sound from a vertically oriented cone; these Model D speakers were a more economical version that still offers warm and rich sound, especially known as being great for rock and roll music.
Ohm is still in business making boutique hi-fi speakers, and these speakers which originally cost $400 a pair in the early 1970s are still worth a $400 trade-in credit towards a new set today. They feature a 10″ woofer and a CTS phenolic ring tweeter packaged in a solid hardwood cabinet with a resistive (aperiodic) port. A resistive port is half-way between an acoustic suspension enclosure and a reflex enclosure, it’s not the most common design. Inside, there’s a 2 uF and a 20 uF crossover capacitor, an inductor, and a rheostat to adjust the tweeter level.
These speakers were used for only a few years in the ’70s, picking up only the tiniest of nicks and dings, before they were put back in their original boxes and stored for the next 40 years. Even with such careful storage, though, the woofer foam had degraded and was due to be replaced – so the first order of business was new foam surrounds.
Then it was to address the crossovers.
Bad capacitors mean bad sound! And this one certainly was bad. It’s supposed to measure 20 uF, but instead is measuring 0.0013 uF. That’s no good at all.
And this one’s showing more ESR than I’d like:
Beautiful classic speakers like this deserve nothing but the best, so I used brand new audiophile grade film crossover capacitors which are exceptionally stable and have a low dissipation factor for unmatched performance.
It was rather interesting – these were purchased as a pair, but inside, used slightly different capacitors. Both of the same value, but one used a single 20 uF bipolar capacitor and the other used a pair of 10 uF in parallel.
Now, it’s time to put the woofers back into the cabinets after cleaning up the gaskets:
Finally, time to package it all back up!
These speakers are for sale! $225. Please contact me for more information.
A local client brought me a radio which was in the family for many years, a cute little “fridge radio” made by Westinghouse from 1945-1947. The same year Westinghouse released this new model of home refrigerator, they also released this Little Jewel radio in the same style as a companion. Many examples of this radio found their way into homes and kitchens over the years and are a great little collectible from the post-war era.
This little radio is a 6-tube AC/DC radio with a series-string tube line-up, 12SK7 12SA7 12SF7 12SJ7 35L6 35Z5. It has an integral tuned loop antenna and an RF Amplifier for great performance.
They sure packed it into here, too. The radio is held in place by two chassis bolts, one in each side and a rod which stabilizes it in place.
The dial scale has badly warped with age, but the grille cloth is nicely intact.
This radio’s owner mentioned that it had been playing but recently cut out. No surprise why – the original parts under the chassis looked to be in pretty bad shape!
Melted, leaking and blown capacitors will cause all sorts of issues – no wonder it wasn’t running like it used to! This radio was pretty cramped underneath the chassis, but there was enough room to install both electrolytic filter capacitors and the cathode bypass capacitor on the output tube under the chassis instead of needing to re-stuff the can on top.
I had a reproduction dial scale made up to replace the warped original, and replaced some tubes which were testing weak.
Finally, it was time to test it out and tweak the alignment trimmers, then back together! It sounds a lot better than I’d expect with such a small radio – the case makes an interesting vented enclosure. On 880 KIXI, you can really hear the low notes, and the vent on the top seems to serve as a port for the speaker.
After being refurbished electrically, this radio is going to perform beautifully for many years. It’s got a rich tone and great audio clarity even more than you might think from such a small speaker.
I recently got to work on something a little bit different – a tube hi-fi stereo console! This particular one, a 1962 Zenith MK2670, was a very high-end unit back in its day. It’s a dual-chassis unit with 19 tubes total, using the 12K25 stereophonic FM tuner and 7K31 stereo amplifier chassis with EL84 outputs. All housed in a beautiful mid-century modern cabinet with built-in stereo speakers featuring 12″ woofers and mid- and high-end compression drivers and horns.
With 19 total tubes, this model features hi-fi integrated speakers with high-efficiency 12″ woofers and mid and tweeter horns, push-pull EL84 output tubes for each channel, and built-in FM Stereo Multiplex decoding for true stereo hi-fi reproduction.
This hi-fi’s owner reported it was working well for several years but started to go downhill shortly before she got in touch to have it fixed. It was taking longer and longer to warm up and sounding more and more distorted, no longer delivering the rich warm sound of a classic hi-fi console. It was good she got in touch – waiting any longer could have led to catastrophic consequences such as component failure or even a fire. I visited her home to test the tubes and pull the chassis, then it was back to my shop for repairs. And what a job it was!
This unit had been serviced a couple of times in its life – there were some ’70s era film capacitors installed, and some of the output tubes had been replaced. Most of the tubes were original Zenith fittings and tested strong, though, so very little needed to be replaced. Since it came into the shop in working condition, too, it made the diagnostic process much easier!
The amplifier circuit is a bit different than most I’ve seen. The negative phase of the output transformers was connected to chassis, and there were two positive phased taps each connected to half of the speakers. It’s an odd arrangement, certainly, which would have let Zenith use woofers of different impedance then the mid/tweeter network without an expensive and complicated impedance matching network. Underneath, though, it’s pretty easy to work on:
Right away there’s some visible damage. This molded ceramic capacitor blew a piece of the ceramic clean off from overheating. It’s unlikely it was doing much of its job at this point. Despite a nice ceramic body and epoxy sealed ends, it’s still an acid-paper/foil capacitor inside subject to failure, and fail it did.
Many of these early disc capacitors were failing as well.
I tested and replaced resistors as necessary, and capacitors. Here’s an in-progress shot showing partial replacement complete. Even the resistors I did remove were very close to spec – Zenith clearly used high quality resistors in this hi-fi. All were shiny with intact bodies and paint, and none had the woody, chalky appearance of a tired carbon resistor.
With the amplifier chassis sorted, it was time to move onto the tuner. It’s nicely shielded on the bottom.
And there’s a lot going on inside.
This radio was build very, very densely and in layers. It’s also a modern hi-fi instrument sensitive to wiring changes, so I had to work without disturbing most of the arrangements. Fortunately, Zenith specified high quality carbon film resistors and they were overwhelmingly within tolerance, so it was just a straightforward capacitor replacement.
Even film capacitors are much different these days. The ’70s 0.47uF 400V capacitor, top, was replaced with a 0.47 uF 630V capacitor about 1/4 the size. Working with a needle-nose pliers in each hand, I was able to thread capacitors into the proper location under component networks without disturbing the top layer.
Now it was time for a power-up test. This particular radio uses an odd multi-tapped output transformer arrangement with drivers hooked up to both taps in the cabinet, so I ended up hooking up 4 distinct speakers for testing.
It fired right up and sounded great! There were a few minor issues to resolve, though. For one, there was a bad volume-invariant hum on the AM band only. This was due to a small short which was corrected. The volume controls were behaving pretty erratically, though, which took some investigation.
The unexpected behavior turned out to be due to a control scheme I hadn’t run into before. The “balance” control isn’t an actual fader; instead, the volume controls for the left and right channel are ganged together with a friction clutch. Turning the outer ring turns both together – but turning the inner ring adjusts the friction clutch allowing one to be turned independently to achieve the left-right effect. At the new set point, then, the outer ring will turn both volume controls together to adjust the loudness equally after the fade is applied. It wasn’t a popular control scheme, being replaced after a couple of years, because many consumers found it to be annoying and counter-intuitive.
After understanding how it worked, however, it turns out that it wasn’t gummed up, it was actually working properly. So, on to the next steps! Adjusting the bias on the channels:
RF and IF Alignment:
Lots of parts came out of this one!
This radio is going to continue to serve faithfully for many years, pumping out a warm and rich hi-fi sound and be a beautiful family heirloom to pass on. They just don’t build them like they used to!
I just had this incredible Yamaha CR-2020 through my shop. It had some major problems which we’ll get to, and an extensive service history already, so this one was a real challenge but I’m happy to say it’s been reconditioned for daily use. It’s got some quirks due to its age, but is one of the most powerful and best-sounding vintage receivers I’ve listened to.
The Yamaha CR-2020 drives 120W/channel into an 8 ohm load and supports 3 pairs of speakers (but only plays 1 or 2 pairs a time), dual phono inputs supporting both moving magnet (MM) and moving coil (MC) pick-ups, tape-copy functionality with a separate output selector, and a variety of tone control and FM Stereo adjustments.
The owner reported the unit was playing, then suddenly went silent and wouldn’t play anymore. Telltale signs of smoke rising from the inside can be seen on the vent slats.
Let’s take a look inside…
An absolutely mammoth transformer, and the two final amplifier modules with enormous heat-sinks. Above the transformer is the power supply section; the far left moving out of the photo is the tuner.
The power supply has had three capacitors replaced but most are original. The lights have been modified at some point as well, although somewhat sloppily.
Yamaha used a drive-shaft type arrangement for the MM/MC switch with two flexible linkages to turn a switch all the way at the rear of the unit from the front panel. The dial arrangement is one long string that wraps around about a half-dozen pulleys. Not only is this a very complex, powerful electrical design it has a lot of physical components as well.
Overall, there’s a lot going on under the hood. It’s time to investigate further.
Here’s a previous repair with a sloppy solder joint visible.
Old and new caps:
It’s generally not recommended to leave old caps in place if some have failed…the others are the same and experienced the conditions, they’re going to go eventually – which is what landed this one back in the shop.
On the underside, the board was badly damaged during the capacitor replacement. It’s tough to repair these old boards without some damage, although that’s a pretty good chunk of foil missing. If a de-soldering iron at too low of a temperature had been used – or a piece of braid – that could have happened pretty easily. All of the joints are pretty cold and looked poorly flowed, though. I re-flowed the ones that looked like it wouldn’t further damage the board with a dollop of new solder.
Underneath the board with the regulator transistors is the rectifier board and massive filter caps.
I see some leakage around the bottom. And there’s evidence of heat from below:
At this point, all the old capacitors in the power supply are candidates for replacement. It’s clear the power supply boards have suffered several failures and need a complete overhaul. There’s quite a few transistors:
More damage. Lifted traces.
The rectifier board with the large filters has quite a few large wires going to it. These are the B+, B- and ground wires for the final boards attached to the rear.
New, computer-grade filter capacitors rated a tiny bit higher than original – all while being slightly smaller.
Nichicon capacitors, some of the highest quality available, were used in this replacement.
On the left, capacitors which definitely failed – either very high ESR, out of specification, or open circuit. On the right, capacitors which were “technically ok” for now.
There’s a handful of caps on the final boards, too.
It’s time to pull the finals.
From right to left to the power resistor: signal common, signal input, b-, b+,
From left to right: TP1 bias meter point (no wire), amplifier output, ground/CT, B+, B-.
Ah yes, I seem to have found the problem:
Looks like something had a real bad time and let the magic smoke out. It’s destroyed a pair of resistors, a small-signal diode, the HW-21468 fuse resistor, a ceramic disc cap, and a driver transistor – that we know of.
Final output transistors. The amplifier board is held on by the base connections which are screw terminals through these.
The failure was so violent it scorched the board and blew one of the legs off the transistor’s case.
That’s a fair amount of dead parts. Time to hook it all back together and test some more.
Powering back up….nothing. The lights come on, voltages appeared, and nothing caught on fire – but there’s no output. Time to do some probing. Initially, I wasn’t even getting a signal out of the pre-amp stage. There are several places along the way to check for the presence of a signal on the volume gang:
After toggling several switches I did get audio to the inputs, finally. The un-failed channel was doing fine, but the other one, not so much.
The speaker protection relay is checking for proper voltages before connecting the contacts.
Something must be dragging down one of the rails. It turns out one of the sense lines was being shorted to ground; moving some wiring around corrected this problem. The relay clicked and engaged, and perfect sound started coming out – from one channel only. It was pretty clear there were some dead transistors which needed replacing also.
I replaced most of the transistors; unfortunately, the wrong part arrived and when installed caused a major short-out of several components and damaged the board with the spark. This was very unfortunate and is the first time anything of the sort has ever happened. So I tracked down a replacement final board, and refurbished that to install in its place.
This one played great as well. I tested them on my bench speakers for quite a while with the guts spread across my workbench; the bench speakers are very inefficient and this allowed the amp to get a decent work-out. Finally, it was time to get everything back together. I fixed up a bad connection to the dial lights where a resistor lead had broken. Then put it all back together.
Time to adjust the bias! Using the oscilloscope, I measured the voltage between TP0 and the speaker output terminal for a 10mV +/- 1 mV voltage difference.
Finally back in the case, and hooked up to my K-Horns for some real live testing.
The tuner section could stand to be refurbished later on to bring broadcast reception up to standard, but other than that, it sounds fantastic. Warm and rich, it consumes the FLAC audio I use for testing easily and pumps out incredibly crisp, accurate sound with a ton of power and headroom to match. It’s great to have it back in operation. I’m probably going to get myself one of these at some point, it would make a great center for my own vintage hi-fi use.
I recently had another Bose 901 Series I equalizer in for the standard repair service. It was from the later part of the Second Production run and so had a mixture of capacitor packages depending on the value.
It looks like the electrolytic capacitors were partially replaced somewhere along the way. The black capacitors had different lead terminations and were clearly hand-soldered versus the crimped factory component leads.
This equalizer got a complete overhaul with all new electrolytic and film capacitors and precision metal film resistors for low noise.
This equalizer will sound like new for many years to come. If you need yours fixed, too, I can help.
I recently had the chance to work on this beautiful Motorola 99-FM21 from 1948, currently owned by the granddaughter of its original owner. It’s been in the family since its purchase new in 1948 and was lovingly cared for the entire time, even after it was no longer in active operation. It really showed, too.
This is a post-WW2 radio when very few radios contained any shortwave bands. This Motorola has the AM Broadcast Band, and the newly developed FM Broadcast Band from 88-108 MHz. That’s right – you can pick up modern radio stations with this tuner. It has a pair of 6V6 tubes for the output (although its bass response is limited due to an undersized output transformer) and a treble roll-off tone control.
The radio looks like it had been serviced one or two times in the past. Most parts were original, but two capacitors looked to have been replaced in the ’50s.
Here’s that small output transformer. To give you an idea of size, it’s a little bigger than two stacked boxes of matches, like a restaurant might give out. A similar hi-fi amp, also driven by a similar pair of 6V6 output tubes, uses a transformer about the size my fist in the same circuit position. The amount of iron in a transformer is directly correlated with its frequency response, so Motorola seems to have cut a corner by fitting this particular transformer. It sounds good, but doesn’t have quite the bass response that’s possible.
This radio’s owner requested the ’50s capacitors be replaced with period units, and the can capacitors restuffed and the shells retained. Not many elect for that additional service as it’s quite time-consuming to perform, but in this case it’s a great choice with the radio being in the same family for so many years. I started with labeled clip-leads in place of each replaced unit to keep the circuit straight. With the schematic to double-check, this ensures error-free service.
Restuffing capacitors involved heating them to melt off the wax, then pulling on the leads until the body of the capacitor was removed. I’d then ream the cylinder, add a new capacitor, seal with polymer clay and dip in wax, then replace in the radio. I found two period-correct capacitors to replace the two ’50s units, as well.
Capacitor re-installation was pretty straightforward:
I also used similar sized electrolytic replacement capacitors which look similar to how a period repair would have been performed. It’s useful to have a bag of donor parts around to provide shells for restuffing.
At this point, I hooked up my phone as a test source and it played loud and clear through the phono input. AM reception was okay, and FM was quite poor, however. It was time to do some further testing.
This radio is one of the first to use integrated couplets, blocks of several components in a single package. In this case, the component in question is a 47K 1/2W resistor paired with two 50pF capacitors. The resistor is reading 73.9K Ohms, which is well outside of its tolerance. This one was replaced with a similar visual appearance carbon composition resistor from IRC.
I replaced quite a few more resistors, and attempted an alignment. First, I tried using the triggered oscilloscope and sweep generator, which even required building some of my own test leads:
Unfortunately, my sweep generator’s FM options are geared towards more modern equipment which deals in whole-number modulation percentages; the Motorola wanted deviations around 2.2% and 1.4% which I couldn’t provide. So I went with the FM Alignment with AM Generator option, using my laboratory signal generator the Leader 3216. The procedure was a rather lengthy one, involving de-tuning the discriminator coil secondary to cause it to respond to AM signals, then tweaking other adjustments for peaks.
After adjusting the IF transformers in order and the RF trimmer for dial tracking, I re-peaked the discriminator primary using an insulated driver to eliminate the AM noise. The FM discriminator is supposed to be only sensitive to frequency deviation; a no-deviation signal (like an AM signal) should produce no sound at all. It was a very touchy alignment, taking about a half an hour of the tiniest of adjustments to null the signal. The curve had a very slope and it was incredibly difficult to peak – similar to the discriminator in the GE F-135, but even more precise because of the much higher frequency (10.7 MHz vs. 455 KHz).
Finally, however, it did peak up and I attached a 300 Ohm twin-lead dipole. The FM antenna has a known impedance, while the AM is a flat-board loop with a terminal for an optional external longwire antenna.
After this alignment I was able to pick up stations across the dial loud and clear on AM and FM, and the phono input performed perfectly. At this point I let it play for several hours hooked to a bench speaker as a burn-in test, then arranged with the owner to return the radio and test it out. Sadly, her home is on the declining edge of a valley which offers exceptionally poor radio reception and there’s nearly nothing to be heard. Where I received nearly all AM stations and many FM stations on the same equipment, there was only a few faint broadcast stations to be heard. We ended up attaching an amplified TV/FM antenna with a 75 ohm output to a 75:300 balun and attaching that to the radio, which vastly improved the FM band – although on some of the strongest local FM broadcasts at that point, now we were driving the front-end of the radio into distortion. So clearly, this wasn’t a great location for radio. However it sounds phenomenal on period music and is going to serve for many years to come.
This is a beautiful cabinet in original condition and with reconditioned electrics is going to be a great conversation piece, keepsake and music player for many years to come.
It must be the season because another Early Production active equalizer turned up to be repaired! This is the earliest equalizer I’ve yet seen, too: Serial 1056. It’s in for the standard overhaul to replace long since failed capacitors and out of tolerance resistors (not to mention dead transistors in this case). It also uses an early style radial lead package for the 0.015 uF signal capacitors I hadn’t encountered before, which were looking pretty ratty by now.
Seeing the mystery-package transistors in this equalizer explains which component the Zener diodes in the previous really were.
The wiring was all the same color for each channel on this model. Later in the series, each switch position had its own color with a stripe indicating the channel. Here I’ve replaced the resistors and capacitors with their replacements, including the upgraded output capacitors. I’m using premium audio capacitors designed for low distortion and with a very low dissipation factor – up to 100x smaller than the electrolytic output capacitors from the factory. These sound excellent even when stock, of course, but when fed with the right source material the improved capacitors are a noticeable difference.
Quite a few of the transistors had failed in this one as well. I can’t get a good photo of the failure, but the seal between where the lead enters the ceramic body of the transistor is discolored in quite a few places. Unsurprisingly, it was quite dead when I tried it out. This wasn’t unexpected but I’m always curious how well the equipment ages when in storage.
I replaced the signal transistors with new 2N3393 in TO-92 cases, and the transistors wired as Zener diodes with a 1N4736. The new transistors have a different basing, however, so they sit 45 degrees offset compared to the originals.
I’ve also added pigtail RCA jacks out the rear sockets. This fully reversible modification preserves the original hardware but allows you to connect to most new RCA cables with thicker shielding. The original jacks were pass-through panel mounted, so the new cabling just goes right through the original hole perfectly.
It cleaned up nicely!
This one looks great, and sounds fantastic. These Series I Active Equalizers are 38-42 years old at this point on their original components and are well into failure, and with this rebuild it’s going to serve reliably for years to come.
A local gentleman brought in his JVC DVD player, model XV-S60, for repairs. It’s a high end unit from around 2001 with some sentimental significance and despite it being a fair bit outside my normal interest, I decided to take this one in on a best-effort basis and see what I can come up with.
It either had a capacitor leak, or some water damage, or possibly both which caused some corrosion inside, and was refusing to play DVDs – only CDs.
With this board being suspect, I located a replacement board which was known to be operational and tested it to verify, then proceeded to perform a complete capacitor replacement to ensure it will have a long lifetime for its owner.
Although not really made to be serviced, the silkscreen nicely indicates polarity for the electrolytic capacitors. It’s only a single-sided board; some ICs and SMD components are on the bottom, and the top side is populated with through-hole components, with jumpers up as needed to cross traces.
After component replacement, I powered it up again to verify operation – DVDs are now coming in great!
I’m not really sure what kind of life to expect out of the refurbished DVD player. The capacitors themselves will be good for a long time, but I don’t know the state of any of the other components or their estimated longevity – laser diodes, controller circuitry, really anything else. The player sat in a damp environment for a little while and has some quirks from being over 12 years old and well-loved at that, but now it should be good for a while.