This is a weird one. I mean, who needs three regenerators? Especially when finding the parts means shipping from multiple countries. This is more about the journey than the destination. I’m also posting it in case anyone attempts the same.
The truth is that that is the actual value of DIY, especially when it is slow, methodical, and without pressure when it is just done for hell and enjoyment of it is therapeutic because it is distracting… okay, until something blows up. It’s a little stressful… but still distracting!
Aside from the fact that I couldn't stop my OCD personality and the therapeutic nature of restoring things. I've been dealing with excessive stress, and I guess, in a way, it was my subconscious just doing a side-line calculation on a therapist vs another Mouser shipment
. This for me though is the real benefit of DIY, and the hidden ROI of it. Yes, DIY can (and if you count hours) probably is more expensive, but the non-monetary gain of DIY is priceless.
Anyway...So I started with a P500 & P300.
Generally, the output devices fail on these, so it’s an excellent place to start.
For the P300, I was lucky enough to get a brand new set of MKJL21193 and MJL21194, these devices are hard to get, with production only restarting later this year or in 2024. While those were being shipped, I decided to tackle the P500.
The P500 is a tricky beast, simple in concept but tricky for other reasons, like heat build-up and the output step-up transformer that puts a significant start-up load on the board.
I replaced the output components, and they failed; I replaced more parts, and it failed. The problem with these units is that they are on 24/7, the combined heat generated cooks the board over time, and every component replacement means another lifted pad or track.
This is the old board, you can spot the issues
So, I did what any rational person would do and traced the board and had a new one made, 5 in fact, so I have spare. Also, a global shortage on MJL21193 & 94 meant I needed a solution for these parts. So I did the second entirely rational thing anyone would do and modelled the entire thing in NI Mutltisim to test a shortlist of output devices. This was an interesting exercise in that I was able to model which components would be generating a lot of heat, and upgrade them before I even started.
Long story short, I repopulated the boards with totally new components. I added connectors for additional capacitance.
I added extra caps, which is a fairly standard mod.
I also tackled the heat problem by adding a Noctua Fan, a more powerful but inaudible one. These are brilliant low-noise fans.
This is the fan in action.
Whenever people complain about fans, these should be a recommended option to try. I played cat and mouse game, running the unit at 50% load, checking the heat, and then updating part spec.
A worst-case scenario would have meant a mod to the chassis, but the Fan and switching out components to reduce the temp made a big difference.
Noctua Fan Video if you are interested:
I also changed some input resistors to aluminium to deal with a massive heat problem on that board. You can see the blackened board in the original area at the top of the board. I also added a ground choke. I also updated the board components to new reccomended specs from PS Audio.
During this time, the parts for the P300 arrived; this was an easy repair, replacing the output transistors, and it was good to go. The heat problem on the P300 is better, it runs at a constant 45 to 50 degrees, but I replaced the fan with a Noctua fan, I had to print a converter for this.
At some point, I updated Schalk, who was kind enough to offer a second P300. The chassis on this one had been hacked a little on the base; it had no fan. As I said, these things run 24/7, so the heat build-up can be brutal. I replaced the output devices and some resistors and then put a Noctua fan in this one. The fan is so quiet that I didn't use a thermostat on this one and let the fan run continuously. I have some thoughts on the thermostat mounting I may address at another time.
I also replaced all the logo globes on all devices, restoration, right?
That's the P500 running a heat lamp for testing. 220V & 50Hz.
How do they sound?
Well, only the P500 is doing duty, and the impact on my equipment is very good. From the forums, opinions on these regenerators are polarising. However, I think it depends on how good your initial power is. In my humble opinion, my system is brilliant sounding, and I can hear the difference. My problem is that I live in an old home, and I recently had to rewire for Solar. This polluted my mains spur for my audio equipment in this room. Out of care for my family, I can't let another electrician onto the property for at least a year!
It may also be bias, I'm also more chilled from the DIY… after all the DIY time. Seriously though, I did have an issue with my power, so maybe that is why.
The P300's all warm and working. The industrial design of these is slightly impractical from a depth POV.
The one P300 will do duty in my office; I just need to sort out my Pass B1 Korg Buffer, which managed to start picking up interference from my office IT setup, which is pretty damn complex. So more slow DIY
I have a few systems so the other P300 may find a home there, or I might run some sensitive test equipment off it.
Future:
I am going to recap the P300s. I need to buy more capacitors. 3300uf 100V D=25 are more challenging to find than one would want for a decent price. For now, though, the caps all look good and measure fine.
I will do a second round of modifications; these are actually because I am not comfortable doing the 24/7, always-on thing. I already do an automated controlled start-up of my entire system. So on the P500 and P300 I will add a Sonof POW to control turn-on. Then an Aurdino to do some automatic power configuration (The P300 resets its settings when powered off entirely and restarts at 60hz instead of 50).
Thanks to
The truth is that that is the actual value of DIY, especially when it is slow, methodical, and without pressure when it is just done for hell and enjoyment of it is therapeutic because it is distracting… okay, until something blows up. It’s a little stressful… but still distracting!
Aside from the fact that I couldn't stop my OCD personality and the therapeutic nature of restoring things. I've been dealing with excessive stress, and I guess, in a way, it was my subconscious just doing a side-line calculation on a therapist vs another Mouser shipment
. This for me though is the real benefit of DIY, and the hidden ROI of it. Yes, DIY can (and if you count hours) probably is more expensive, but the non-monetary gain of DIY is priceless.Anyway...So I started with a P500 & P300.
Generally, the output devices fail on these, so it’s an excellent place to start.
For the P300, I was lucky enough to get a brand new set of MKJL21193 and MJL21194, these devices are hard to get, with production only restarting later this year or in 2024. While those were being shipped, I decided to tackle the P500.
The P500 is a tricky beast, simple in concept but tricky for other reasons, like heat build-up and the output step-up transformer that puts a significant start-up load on the board.
I replaced the output components, and they failed; I replaced more parts, and it failed. The problem with these units is that they are on 24/7, the combined heat generated cooks the board over time, and every component replacement means another lifted pad or track.
This is the old board, you can spot the issues
So, I did what any rational person would do and traced the board and had a new one made, 5 in fact, so I have spare. Also, a global shortage on MJL21193 & 94 meant I needed a solution for these parts. So I did the second entirely rational thing anyone would do and modelled the entire thing in NI Mutltisim to test a shortlist of output devices. This was an interesting exercise in that I was able to model which components would be generating a lot of heat, and upgrade them before I even started.
Long story short, I repopulated the boards with totally new components. I added connectors for additional capacitance.
I added extra caps, which is a fairly standard mod.
I also tackled the heat problem by adding a Noctua Fan, a more powerful but inaudible one. These are brilliant low-noise fans.
This is the fan in action.
Whenever people complain about fans, these should be a recommended option to try. I played cat and mouse game, running the unit at 50% load, checking the heat, and then updating part spec.
A worst-case scenario would have meant a mod to the chassis, but the Fan and switching out components to reduce the temp made a big difference.
Noctua Fan Video if you are interested:
I also changed some input resistors to aluminium to deal with a massive heat problem on that board. You can see the blackened board in the original area at the top of the board. I also added a ground choke. I also updated the board components to new reccomended specs from PS Audio.
During this time, the parts for the P300 arrived; this was an easy repair, replacing the output transistors, and it was good to go. The heat problem on the P300 is better, it runs at a constant 45 to 50 degrees, but I replaced the fan with a Noctua fan, I had to print a converter for this.
At some point, I updated Schalk, who was kind enough to offer a second P300. The chassis on this one had been hacked a little on the base; it had no fan. As I said, these things run 24/7, so the heat build-up can be brutal. I replaced the output devices and some resistors and then put a Noctua fan in this one. The fan is so quiet that I didn't use a thermostat on this one and let the fan run continuously. I have some thoughts on the thermostat mounting I may address at another time.
I also replaced all the logo globes on all devices, restoration, right?
That's the P500 running a heat lamp for testing. 220V & 50Hz.
How do they sound?
Well, only the P500 is doing duty, and the impact on my equipment is very good. From the forums, opinions on these regenerators are polarising. However, I think it depends on how good your initial power is. In my humble opinion, my system is brilliant sounding, and I can hear the difference. My problem is that I live in an old home, and I recently had to rewire for Solar. This polluted my mains spur for my audio equipment in this room. Out of care for my family, I can't let another electrician onto the property for at least a year!
It may also be bias, I'm also more chilled from the DIY
… after all the DIY time. Seriously though, I did have an issue with my power, so maybe that is why.The P300's all warm and working. The industrial design of these is slightly impractical from a depth POV.
The one P300 will do duty in my office; I just need to sort out my Pass B1 Korg Buffer, which managed to start picking up interference from my office IT setup, which is pretty damn complex. So more slow DIY
I have a few systems so the other P300 may find a home there, or I might run some sensitive test equipment off it.
Future:
I am going to recap the P300s. I need to buy more capacitors. 3300uf 100V D=25 are more challenging to find than one would want for a decent price. For now, though, the caps all look good and measure fine.
I will do a second round of modifications; these are actually because I am not comfortable doing the 24/7, always-on thing. I already do an automated controlled start-up of my entire system. So on the P500 and P300 I will add a Sonof POW to control turn-on. Then an Aurdino to do some automatic power configuration (The P300 resets its settings when powered off entirely and restarts at 60hz instead of 50).
Thanks to
- Schalk. This project kept me sane.
- Bob at PS Audio has such a relaxed attitude to this project.
- This forum on Zelfblou is a fantastic read: Reparatiepoging PS Audio Powerplant 500. - forum.zelfbouwaudio.nl
