LOL, I like that special effect with the ticking clock when you were testing the multi-cap can! (around 8:25 in the video). There's no doubt of your expertise in the field of electronics, (and probably several other fields), but I have to believe that you also had quite a bit of experience in making instructional videos! Seriously, these videos (not just the MC2105, but the Dynaco and every one I've watched so far), may sound unappealing to watch to many people who aren't that interested in electronics. I know many people who would cringe at the thought of watching this kind of video. However, if they started watching one of yours, they'd find the videos are presented in such a way that makes them want to continue watching because of the clarity in the explanations of what you're doing. I really must say that they're a pleasure to watch and I wish I could watch more of them at a time. However, I have to use what I've learned before I forget it and then move on to the next video. Even then, I still replay the video several times to double check myself. I don't want to risk harming the amp so I'm working slowly, carefully and keeping things as clean as possible. It was in a condition that I could have easily sold it for more than twice what I paid w/o ever having done any upgrading. However, that's if I ever wanted to sell it, (which I don't). I bought this MC2105 at a ridiculously good price near the end of 2019 from the original owner. Actually, from his daughter because her father passed away a year earlier. It was interesting to hear her reason for not selling it sooner: She told me that she thought her father bolted it down to the cabinet it rested on. It wasn't until a friend came and pointed out that there were no bolts coming up from underneath the thick wooden top of the cabinet that she started to question that theory. The friend told her that the only way he could have bolted it down was by driving wood-lag bolts through the four amp legs from the inside the amp's bottom cover and down into the thick wooden cabinet table, LOL. That's when they decided to try lifting it and were astonished to find that it weighed nearly 70 lbs! Rich
They are amazing. I have one that has been a bass amplifier, a PA amp, a studio monitor amp, and now is a bass amp again. I also have another I got on eBay, marked as parts only, but it turns out that it works well and will get the restoration treatment. scontent-den4-1.xx.fbcdn.net/v/t1.0-9/77132868_10221356472850928_3567398886869827584_o.jpg?_nc_cat=104&_nc_sid=1480c5&_nc_ohc=d5-XHb16DZcAX-E1aPS&_nc_ht=scontent-den4-1.xx&oh=982181a2627537d3048e66225f556524&oe=5F0A7F11
(Please note that I posted this second comment before I realized that you had replied to the question regarding the DeOxit): OK, I watched this video twice now, particularly the last section regarding the tests. As you mentioned in an earlier reply, you were having trouble with the Gain Pots and I can see that. In fact, I was concerned about that being a possible problem with my amp and reason for a softer left channel output than the right. I blamed it on channel balance, recording balance differences, and EQ balance differences but when it came down to it, my excuses couldn't explain some of the conditions. McIntosh is awful proud of their Gain Potentiometers. "Brian", (Part tech at Mac), quoted me $80 for each Pot! However, I refused to comprise on these even though I could have bought 10 Gain Pots made in China for the price of one Pot from Mac. I bought two gain pots from Mac and with $25 shipping, TTL came to just under $190. That's more than I paid for the Mac MC2105 Faceplate! Anyway, the new Pots are 240K Ohms and the ones I'm replacing are still in the amp. In circuit, the old Pots were giving me very different resistance readings. They both had about the same max resistance of about 215K Ohms, but the minimum resistance from the Left channel pot was 23.5 Ohms, while the minimum from the right was 117.5 Ohms. Again, I was testing them in circuit so I'll be retesting them after I take them out. Still, I would have expected the readings to be opposite, with the left channel having a minimum of 117.5 Ohms. (It's possible that I mixed myself up because the amp was upside down, but I thought I took that in consideration). NOW: I don't have an Audi Generator. I DO have a Variac (0v-130V, 5 amp) and an oscilloscope, (as well as a signal function generator, if that helps). Do you think I can do a similar test that would offer the same ultimate information that you're after in the tests that your doing here (at about 17:40 in the video)? I bought two 8 Ohm x 25W and two 8 Ohm x 100W dummy resistors to do some tests on my Open Reel decks and this amp. My point is that I would pipe the output signal through the resistors, (8 Ohm x 25W), into the left and right channels of the scope. Thanks, Rich
Rich, with an oscilloscope and dummy loads you can do a power test and square wave test. For the power test, you need to input a 1 kHz sine wave at the correct voltage. For the square wave test, you’ll need a similar signal, but as a square, not a sine. The other tests will require more sophisticated equipment such as spectrum analyzer and distortion meter. Note that the amp can put out quite a bit more than 100 watts, so your 100 watt resistors may not be up to the task. Any tests you do at full power must be done very, very quickly even with more properly sized resistors. You may not want to do a full power test with those.
@@FluxCondenser Thank you Chris!! I bought the 100W resistors for a different project, (I was playing around with a 50W (25W x 2) Radio Shack integrated amp). In fact, I may actually practice on that old Radio Shack amp before I commit myself to the Mac. However, I don't plan to do any full power tests on the Mac regardless. I'm not near your understanding of this stuff and can only go to a certain degree. Then, if I don't detect any issues, I'll have to accept that all is well. You would have laughed your head off watching me handle the Leakage tester last night, LOL. I'm sure I would have driven anyone to the point of yelling, "will you just get on with it?!" As I proceeded with a calibration test of the unit, I checked, double checked, and rechecked everything before turning the thing on. I was doing that through the entire process of testing capacitors as well. I imagine I'm always going to be exceptionally careful with that thing because I am all too aware of the serious punch it can deliver if I get the least bit careless or forgetful. The Allied Knight R/C Tester I have isn't near as sophisticated as the Heathkit, but it was put together very well by an expert in electronics years ago, who seemed to be as meticulous as you, (and I'm learning, for good reason). I say that because he checked off each step of the assembly and made notes. Rich BTW: The seller, (also well versed in electronics), offered me a tip in a note when he shipped the Leakage tester to me. He said that he had recently found out that a DMM (or some other measuring instrument), could be placed in the circuit when doing cap tests. That would allow for readings of DCma stats in addition to referring to the eye. I'm not sure of the configuration, though. I think he means connecting the positive lead of the Cap under test to the Tester's positive post. Then connection the DMM's positive lead to the negative lead of the Cap, followed by connecting the DMM's the negative lead to the negative post of the tester. Does that sound right? I'm afraid to try it until I know how that setup is done and how knowing the cap's DCma would be helpful. Rich
Hi Chris, Would DeOxit be a good choice for cleaning those same selectors and various controls? I have DeOxit F5 & D5 and a generic brand of Electronics lubricant.
Rich, again, for the level controls I’d be very careful. I used Nutrol control cleaner on mine which is usually very gentle. One of the level controls was fine after, but on the other the track disintegrated. I’m still not sure what happened there. Perhaps the cleaner damaged it, or it was already bad. I know that the control worked fine before, though and was just “scratchy.” The composition of the track was a plastic or vinyl, so if you do want to attempt this, I’d try Fader F5 as it is designed for plastic controls. For the selector switch any control cleaner will do.
Do you think the Heathkit IT-22 can do the job checking the caps in the MC-2105 with reasonable accuracy? I have a shot at getting one for someplace between $50 & $75. Rich
No, the IT-22 only tests for opens or shorts in-circuit. And, it won’t even test electrolytics from my understanding. For the large caps, the main concern is parallel leakage and you need something like the IT-11 or IT-28. Those will measure caps at actual operating voltage for parallel leakage. They can test capacitance, but the means by which they do that isn’t super user-friendly. For smaller electrolytics an ESR meter is useful. Although, no matter what size the electrolytic, they can, and should be measured for both equivalent series resistance and parallel leakage. If you’re not likely to use such a tester again, you may just be better off replacing the capacitor. From my experience, there’s a good chance that at least one of the sections is gone and it’s really due to be replaced at this time anyway for future reliability. Hope that helps.
@@FluxCondenser Well, you have saved me from myself! I've spent too much time searching and I'm just going to have to replace the caps in the multi-cap can. There are none available that fall in the spec window that I need. It's not worth buying an IT-28 and even an IT-11 that I found was over $250 and only good "for parts". Thank you, Rich
My pleasure. Yeah Heathkit’s leakage testers are still in high demand as it’s difficult to find an affordable modern tester that performs that function.
@@FluxCondenser Thanks, Oh I found some modern ones by B&K but they start at about $1300 and go up quickly from there. I did find one leakage tester, (an Allied Knight Cap/Bridge Leakage tester) that an electronics engineer is selling for $160 or "Make Offer". I think he'd let it go for $130 plus the shipping, which is $25. I posted the link to it below. I'm considering this one. It's a much more simple unit than the IT-28, or even the IT-11. When I consider the fact that I have that Sansui AU-919 I'm planning to recap later, this Allied Knight may be a more reasonable investment. Take a look and see what you think (I may make that offer): www.ebay.com/itm/Vintage-Allied-Knight-Capacitor-Bridge-Leakage-Tester-Functioning/324517216733?_trkparms=aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D20131231084308%26meid%3Df591b839ef344b22ba1f5a22d914b8a3%26pid%3D100010%26rk%3D4%26rkt%3D12%26sd%3D324488691757%26itm%3D324517216733%26pmt%3D0%26noa%3D1%26pg%3D2047675%26algv%3DDefaultOrganicWithAblationExplorer%26brand%3DKnight&_trksid=p2047675.c100010.m2109
I wound up making a $120 offer for that Allied Knight leakage tester. I really didn't think he'd accept it but he did! After shipping costs and tax I spent about $150 for it, which is where I was drawing the line. It should be here in a week. Rich
Hi, You've been a great help to me on my MC2105 and you probably remembered that I've had no luck in finding a replacement multi cap can. As per your suggestion, I found the video you've released on the Dynaco amp, (Dynaco SCA-80Q Amplifier Kit Part 2), which I've yet to review for info on building a multi-cap terminal. However, I wanted to test that multi-cap can first and followed your suggestion to watch this part of the MC2105 video set. I've spent hundreds on instruments & special tools to do this job as proficiently as I can. I really would like to avoid buying yet some more instruments for this job because it's likely that I won't use them again except for maybe a very far-away project recapping a Sansui AU919. I own an analog oscilloscope (BK Precision 2120) and a digital signal function generator. In addition, I own an analog AC Meter and of course, a DVMM. between these four instruments, is there anyway I can use them to reliably test capacitors? The Heathkit IT-28 looks expensive enough for me to try and find some other way to accomplish this test. Thank you, Rich PS You know, I haven't been able to find any indication of your name, (first or last). Not even on your Flux Condenser page and I'd rather not call out "Hey You" lol. I know that these days, any personal info can be just that much more leverage a scammer can use. However, if you prefer not to give your first name, could you give me an alias that I can refer to you as? (thanks again)
Apparently the Dynaco job isn't in part 2. I can't seem to find the stage where you build a multi-cap terminal. My search for the "P1" on that Dynaco job isn't producing a link. I found "P2" on your Flux Condenser page but not part 1. I need to try a different search but if you have that link and see this post, would you post it in a reply? Thank you, Rich
Hi, Rich. I’m running out the door, but wanted to quickly reply to you. The link that shows the terminal strip being installed is here: ruclips.net/video/JE_2rjP6Rxs/видео.html
Rich, my actual name is Chris, but I’ve gotten used to being called Flux. To test caps, you really need to evaluate capacitance, ESR and parallel leakage. You can get an ESR meter that measures capacitance. And leakage meters that measure everything (rare), but you’ll usually need at least two or three devices. A multimeter isn’t the right tool for doing all those jobs. Also, be careful if you get a Heathkit leakage tester. These things put up to 600 volts at the leads so extreme caution must be used.
@@FluxCondenser Thank you, Chris! Please don't let me keep you and if I ever post when you're involved in something, go on with it, no worries. I will simply keep checking back periodically. Frankly, I expect that you won't always be able to respond so soon after I post, so it's not a problem. Rich PS I used to think that a scope to check and/or test anything but I'm finding out more and more that's not the case.
Those pots aren't available anymore. But you can make them out of two separate pots. I think I have the part numbers somewhere. In regards to the headphone being wired backwards, most 2105s are like that. They were built before the standardization many people swap them to today's standard. They might be out of phase too double check that.
Thanks, Sean. Stay tuned for the next video for my solution to the potentiometer issue. Good to know about the headphone jack. I hadn’t heard that. The rewiring will be shown in an upcoming video as well.
Edwin Hurwitz Thanks for your input, Edwin. Yeah, the design makes for a great headphone amp, power-wise (it’s truly impressive, actually), but the dual level controls make it a bit impractical for day-to-day headphone use. Still, it’s a nice addition and made diagnosing the distortion a bit easier. In an upcoming episode I’ll rewire the jack for the now-accepted left/right norm.
LOL, I like that special effect with the ticking clock when you were testing the multi-cap can! (around 8:25 in the video). There's no doubt of your expertise in the field of electronics, (and probably several other fields), but I have to believe that you also had quite a bit of experience in making instructional videos!
Seriously, these videos (not just the MC2105, but the Dynaco and every one I've watched so far), may sound unappealing to watch to many people who aren't that interested in electronics. I know many people who would cringe at the thought of watching this kind of video. However, if they started watching one of yours, they'd find the videos are presented in such a way that makes them want to continue watching because of the clarity in the explanations of what you're doing.
I really must say that they're a pleasure to watch and I wish I could watch more of them at a time. However, I have to use what I've learned before I forget it and then move on to the next video. Even then, I still replay the video several times to double check myself.
I don't want to risk harming the amp so I'm working slowly, carefully and keeping things as clean as possible. It was in a condition that I could have easily sold it for more than twice what I paid w/o ever having done any upgrading. However, that's if I ever wanted to sell it, (which I don't).
I bought this MC2105 at a ridiculously good price near the end of 2019 from the original owner. Actually, from his daughter because her father passed away a year earlier. It was interesting to hear her reason for not selling it sooner:
She told me that she thought her father bolted it down to the cabinet it rested on. It wasn't until a friend came and pointed out that there were no bolts coming up from underneath the thick wooden top of the cabinet that she started to question that theory.
The friend told her that the only way he could have bolted it down was by driving wood-lag bolts through the four amp legs from the inside the amp's bottom cover and down into the thick wooden cabinet table, LOL. That's when they decided to try lifting it and were astonished to find that it weighed nearly 70 lbs!
Rich
When your finished you are going to have one heck of an amplifier.
They are amazing. I have one that has been a bass amplifier, a PA amp, a studio monitor amp, and now is a bass amp again. I also have another I got on eBay, marked as parts only, but it turns out that it works well and will get the restoration treatment. scontent-den4-1.xx.fbcdn.net/v/t1.0-9/77132868_10221356472850928_3567398886869827584_o.jpg?_nc_cat=104&_nc_sid=1480c5&_nc_ohc=d5-XHb16DZcAX-E1aPS&_nc_ht=scontent-den4-1.xx&oh=982181a2627537d3048e66225f556524&oe=5F0A7F11
That's the plan!
(Please note that I posted this second comment before I realized that you had replied to the question regarding the DeOxit):
OK, I watched this video twice now, particularly the last section regarding the tests. As you mentioned in an earlier reply, you were having trouble with the Gain Pots and I can see that. In fact, I was concerned about that being a possible problem with my amp and reason for a softer left channel output than the right. I blamed it on channel balance, recording balance differences, and EQ balance differences but when it came down to it, my excuses couldn't explain some of the conditions.
McIntosh is awful proud of their Gain Potentiometers. "Brian", (Part tech at Mac), quoted me $80 for each Pot! However, I refused to comprise on these even though I could have bought 10 Gain Pots made in China for the price of one Pot from Mac.
I bought two gain pots from Mac and with $25 shipping, TTL came to just under $190. That's more than I paid for the Mac MC2105 Faceplate!
Anyway, the new Pots are 240K Ohms and the ones I'm replacing are still in the amp. In circuit, the old Pots were giving me very different resistance readings.
They both had about the same max resistance of about 215K Ohms, but the minimum resistance from the Left channel pot was 23.5 Ohms, while the minimum from the right was 117.5 Ohms. Again, I was testing them in circuit so I'll be retesting them after I take them out. Still, I would have expected the readings to be opposite, with the left channel having a minimum of 117.5 Ohms. (It's possible that I mixed myself up because the amp was upside down, but I thought I took that in consideration).
NOW: I don't have an Audi Generator. I DO have a Variac (0v-130V, 5 amp) and an oscilloscope, (as well as a signal function generator, if that helps). Do you think I can do a similar test that would offer the same ultimate information that you're after in the tests that your doing here (at about 17:40 in the video)?
I bought two 8 Ohm x 25W and two 8 Ohm x 100W dummy resistors to do some tests on my Open Reel decks and this amp. My point is that I would pipe the output signal through the resistors, (8 Ohm x 25W), into the left and right channels of the scope.
Thanks,
Rich
Rich, with an oscilloscope and dummy loads you can do a power test and square wave test. For the power test, you need to input a 1 kHz sine wave at the correct voltage. For the square wave test, you’ll need a similar signal, but as a square, not a sine. The other tests will require more sophisticated equipment such as spectrum analyzer and distortion meter. Note that the amp can put out quite a bit more than 100 watts, so your 100 watt resistors may not be up to the task. Any tests you do at full power must be done very, very quickly even with more properly sized resistors. You may not want to do a full power test with those.
@@FluxCondenser Thank you Chris!! I bought the 100W resistors for a different project, (I was playing around with a 50W (25W x 2) Radio Shack integrated amp). In fact, I may actually practice on that old Radio Shack amp before I commit myself to the Mac.
However, I don't plan to do any full power tests on the Mac regardless. I'm not near your understanding of this stuff and can only go to a certain degree. Then, if I don't detect any issues, I'll have to accept that all is well.
You would have laughed your head off watching me handle the Leakage tester last night, LOL. I'm sure I would have driven anyone to the point of yelling, "will you just get on with it?!"
As I proceeded with a calibration test of the unit, I checked, double checked, and rechecked everything before turning the thing on. I was doing that through the entire process of testing capacitors as well.
I imagine I'm always going to be exceptionally careful with that thing because I am all too aware of the serious punch it can deliver if I get the least bit careless or forgetful.
The Allied Knight R/C Tester I have isn't near as sophisticated as the Heathkit, but it was put together very well by an expert in electronics years ago, who seemed to be as meticulous as you, (and I'm learning, for good reason). I say that because he checked off each step of the assembly and made notes.
Rich
BTW: The seller, (also well versed in electronics), offered me a tip in a note when he shipped the Leakage tester to me.
He said that he had recently found out that a DMM (or some other measuring instrument), could be placed in the circuit when doing cap tests. That would allow for readings of DCma stats in addition to referring to the eye.
I'm not sure of the configuration, though. I think he means connecting the positive lead of the Cap under test to the Tester's positive post. Then connection the DMM's positive lead to the negative lead of the Cap, followed by connecting the DMM's the negative lead to the negative post of the tester.
Does that sound right? I'm afraid to try it until I know how that setup is done and how knowing the cap's DCma would be helpful.
Rich
Hi Chris, Would DeOxit be a good choice for cleaning those same selectors and various controls? I have DeOxit F5 & D5 and a generic brand of Electronics lubricant.
Rich, again, for the level controls I’d be very careful. I used Nutrol control cleaner on mine which is usually very gentle. One of the level controls was fine after, but on the other the track disintegrated. I’m still not sure what happened there. Perhaps the cleaner damaged it, or it was already bad. I know that the control worked fine before, though and was just “scratchy.” The composition of the track was a plastic or vinyl, so if you do want to attempt this, I’d try Fader F5 as it is designed for plastic controls. For the selector switch any control cleaner will do.
Do you think the Heathkit IT-22 can do the job checking the caps in the MC-2105 with reasonable accuracy? I have a shot at getting one for someplace between $50 & $75.
Rich
No, the IT-22 only tests for opens or shorts in-circuit. And, it won’t even test electrolytics from my understanding. For the large caps, the main concern is parallel leakage and you need something like the IT-11 or IT-28. Those will measure caps at actual operating voltage for parallel leakage. They can test capacitance, but the means by which they do that isn’t super user-friendly.
For smaller electrolytics an ESR meter is useful. Although, no matter what size the electrolytic, they can, and should be measured for both equivalent series resistance and parallel leakage.
If you’re not likely to use such a tester again, you may just be better off replacing the capacitor. From my experience, there’s a good chance that at least one of the sections is gone and it’s really due to be replaced at this time anyway for future reliability. Hope that helps.
@@FluxCondenser Well, you have saved me from myself! I've spent too much time searching and I'm just going to have to replace the caps in the multi-cap can. There are none available that fall in the spec window that I need. It's not worth buying an IT-28 and even an IT-11 that I found was over $250 and only good "for parts".
Thank you,
Rich
My pleasure. Yeah Heathkit’s leakage testers are still in high demand as it’s difficult to find an affordable modern tester that performs that function.
@@FluxCondenser Thanks, Oh I found some modern ones by B&K but they start at about $1300 and go up quickly from there.
I did find one leakage tester, (an Allied Knight Cap/Bridge Leakage tester) that an electronics engineer is selling for $160 or "Make Offer". I think he'd let it go for $130 plus the shipping, which is $25. I posted the link to it below. I'm considering this one. It's a much more simple unit than the IT-28, or even the IT-11.
When I consider the fact that I have that Sansui AU-919 I'm planning to recap later, this Allied Knight may be a more reasonable investment. Take a look and see what you think (I may make that offer):
www.ebay.com/itm/Vintage-Allied-Knight-Capacitor-Bridge-Leakage-Tester-Functioning/324517216733?_trkparms=aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D20131231084308%26meid%3Df591b839ef344b22ba1f5a22d914b8a3%26pid%3D100010%26rk%3D4%26rkt%3D12%26sd%3D324488691757%26itm%3D324517216733%26pmt%3D0%26noa%3D1%26pg%3D2047675%26algv%3DDefaultOrganicWithAblationExplorer%26brand%3DKnight&_trksid=p2047675.c100010.m2109
I wound up making a $120 offer for that Allied Knight leakage tester. I really didn't think he'd accept it but he did! After shipping costs and tax I spent about $150 for it, which is where I was drawing the line. It should be here in a week.
Rich
What wattage bulb do you use for your dim bulb tester?
Jason, check out this other video of mine for advice on that: Build This Dim Bulb Current Limiter
ruclips.net/video/6SXPj6HFY-Y/видео.html
Can u check filter caps with a reg fig volt meter . I don’t have a cap tester and vm seems to have max of 200 uf?
Phenom....
Thanks, Vinyl Guru. I enjoy you channel.
Hi,
You've been a great help to me on my MC2105 and you probably remembered that I've had no luck in finding a replacement multi cap can. As per your suggestion, I found the video you've released on the Dynaco amp, (Dynaco SCA-80Q Amplifier Kit Part 2), which I've yet to review for info on building a multi-cap terminal. However, I wanted to test that multi-cap can first and followed your suggestion to watch this part of the MC2105 video set.
I've spent hundreds on instruments & special tools to do this job as proficiently as I can. I really would like to avoid buying yet some more instruments for this job because it's likely that I won't use them again except for maybe a very far-away project recapping a Sansui AU919. I own an analog oscilloscope (BK Precision 2120) and a digital signal function generator.
In addition, I own an analog AC Meter and of course, a DVMM. between these four instruments, is there anyway I can use them to reliably test capacitors? The Heathkit IT-28 looks expensive enough for me to try and find some other way to accomplish this test.
Thank you,
Rich
PS You know, I haven't been able to find any indication of your name, (first or last). Not even on your Flux Condenser page and I'd rather not call out "Hey You" lol. I know that these days, any personal info can be just that much more leverage a scammer can use. However, if you prefer not to give your first name, could you give me an alias that I can refer to you as? (thanks again)
Apparently the Dynaco job isn't in part 2. I can't seem to find the stage where you build a multi-cap terminal. My search for the "P1" on that Dynaco job isn't producing a link. I found "P2" on your Flux Condenser page but not part 1. I need to try a different search but if you have that link and see this post, would you post it in a reply? Thank you,
Rich
Hi, Rich. I’m running out the door, but wanted to quickly reply to you. The link that shows the terminal strip being installed is here: ruclips.net/video/JE_2rjP6Rxs/видео.html
And this one shows the terminal strip being wired and the explanation of wiring. ruclips.net/video/5HZDTS6bSbQ/видео.html
Rich, my actual name is Chris, but I’ve gotten used to being called Flux. To test caps, you really need to evaluate capacitance, ESR and parallel leakage. You can get an ESR meter that measures capacitance. And leakage meters that measure everything (rare), but you’ll usually need at least two or three devices. A multimeter isn’t the right tool for doing all those jobs. Also, be careful if you get a Heathkit leakage tester. These things put up to 600 volts at the leads so extreme caution must be used.
@@FluxCondenser Thank you, Chris! Please don't let me keep you and if I ever post when you're involved in something, go on with it, no worries. I will simply keep checking back periodically. Frankly, I expect that you won't always be able to respond so soon after I post, so it's not a problem.
Rich
PS I used to think that a scope to check and/or test anything but I'm finding out more and more that's not the case.
Those pots aren't available anymore. But you can make them out of two separate pots. I think I have the part numbers somewhere. In regards to the headphone being wired backwards, most 2105s are like that. They were built before the standardization many people swap them to today's standard. They might be out of phase too double check that.
Thanks, Sean. Stay tuned for the next video for my solution to the potentiometer issue. Good to know about the headphone jack. I hadn’t heard that. The rewiring will be shown in an upcoming video as well.
@@FluxCondenser Both of my 2105s are wired backwards. They have a lot of gain, so I don't use them for headphones that often.
Edwin Hurwitz Thanks for your input, Edwin. Yeah, the design makes for a great headphone amp, power-wise (it’s truly impressive, actually), but the dual level controls make it a bit impractical for day-to-day headphone use. Still, it’s a nice addition and made diagnosing the distortion a bit easier. In an upcoming episode I’ll rewire the jack for the now-accepted left/right norm.