Lovely approach , on the other tech , as a player , I take same approach , constructive not destructive .I always learn even in the most unlikely situation .,,,,,Now back to business , lol , love the systematic approach to said issue , ..Cheers
Your videos should be required viewing for Fender amps, as important as the booklet/ manual that we all ought to read. It can take a life-time of trial and error and evening classes to learn that the various layouts and how/why they work. The BMT tone stack is worth a video or 2 to help users understand why the amp reacts as it does. Thanks, great video .
Great video - I'm working on my own TR and have a question - is the heater fuse @ XF2 unnecessary? I see with the mod it is no longer in the circuit. I'm also assuming that the black/white heater wires from the board could be removed.
A customer just dropped one off to me that blew the fuse because someone shot the power transformer on the utility pole at the party he was playing. Took out two of the tubes as well, they blew my multimeter fuse and my BK auto transformer fuse.
@@vintagetubeamplifiersSo it was a power surge from... why tf wd someone shoot a transformer on a pole!?! Cowboys! Edit: us Aussies usually drink at parties... but we're a bit weird!
When you let an amp run after repairs/mods, in this vid you mentioned 12 hrs, do you leave it in stand-by or just turn the volume down and leave it in play and check on it later?
12 hours of playing a loop into a dummy load and I can hear the output of the dummy load through a Redbox cab simulator - I check that sporadically through the 12 hours.
I can deal with the PCB instead eyelet main board but believe the amp would be better served without the front control board and done in old school fashion. Am I wrong or splitting hairs on this?
The board mounted pots and jacks are not bad, if the solder joints are checked occasionally. The pots are good quality and the circuit sounds good with this setup. And they’re consistent and lower the cost for the buyer. I guess I’m saying, “Are they ideal? No. But are they detrimental? Also no.”
Do the original versions of this Twin Reverb always have PCBs like this "reissue"? BTW I had a 100watt twin many years ago as my first "real" amp and when I had the volume on 2 all if the plates, dishes etc stored in a big antique dresser in the dining room next door would shake and rattle when you strummed a chord! Great clean sound though😁
Could someone have used silicon under the dog house cover due to a rattle? I've never heard of it before but it's one of the only logical things I could come up with.
Youve worked on alot of amps, what your favorite speaker brand and type. For blues and midgain stuff. Im struggle finding a speaker i like for prs hdrx20 amp. Ive tried 1 x12 2x12 1x 10 2 x10 of alnico and afew ceramics. But i havent found the right speaker yet. I build my amps around a speaker or set of speakers, that how i know what caps and resistors to use in the tone stack. Since i didnt build this i cant find the perfect speaker. Wondered your op.
How often do you find yourself in this position? The tech before you did a good job, but the customer is super picky and wants something done better than is reasonable? I ask because I expect to encounter people like this once I start servicing amps and I'm not sure how to deal with them.
Not quite that drastic. Customer had work done by a different tech, amp didn’t work when he got it back, he was worried and brought it to me. I was able to reassure the customer. But it was a very reasonable thing to do - most owners wouldn’t know if a tech did something wrong - they only know if it doesn’t work or is noisy etc. If you want to do this professionally, I guess the lesson I’d want you to take away is it’s ok to say “the competition” did good work. Don’t find “fault” just to prop yourself up. I’m glad this guy is doing good work - I’m already slammed and have to turn work away. Good to know I can recommend him in the future. If he sees this video, he’ll feel good about it. And if he didn’t know about the heater and thermistor issues, he does now. So even better. For everyone.
After owning quite a few different brands amps I can honestly say the Fender board in this build is of the cheaper variety. With cheap components comes problems even in good designs. Ymmv.
You mentioned a bad/weak ground could cause the mids to go crazy with the 100k pot. Why isn't what the owner heard a normal function of the 100k pot, turned up, lifting the tone stack from the path? David Allen (and perhaps others) calls that a "raw" control and the 100k pot mod is intended to make a Fender amp sound more "tweedish" (which I personally don't care for). On the other hand, when you turned the mids all the way up, it did not have that characteristic. May have missed something, but, as the curious owner of a Sweet Spot, I have to ask. Thanks
The Fender TMB tone stack is considered "lossy." e.g. it send a lot of the audio signal to ground. Those "raw" controls increase the tone stacks resistance to ground, thus retaining more (sometimes much more) of the gain from prior amp stages. If subsequent amp stages (e.g. reverb) are not designed to accommodate that sort of signal level then you can get all sorts of unpleasant behavior including oscillation. Even worse might by the sorts of things you dont hear, but can pose a long term risk to your amp's health.
@@PsionicAudio That makes sense. Thanks. I wonder now if the owner's observation didn't coincide with added/excess mids at higher volume, and he didn't like the result, thinking it a defect.
@@ThomasD66 That, also, makes sense. It's the excess preamp gain from the 100k pot (turned up, at higher volume) that creates the sound I don't care for. Doesn't sound like drive, breakup, what have you, to me. Just doesn't sound good to me (and, perhaps, to the owner of this Twin), though I understand many like it just fine.
Nah, he said both channels were really loud and distorted and the reverb squealed. I’ve moved wires and tapped on everything, can’t replicate. But at least he knows the tech he used did a good job.
![I.N "HALLUCINATION" | [Stray Kids : SKZ-PLAYER]](http://i.ytimg.com/vi/n5B5q1Hwt_U/mqdefault.jpg)
It's a rare yet encouraging thing to see decently done previous work.
It's not a pleasant feeling discovering the horror that we usually find.
I’ve seen horrible solder joints
Nice validation of the previous tech!
I’m glad to be able to do that. I don’t actually like delivering grim prognoses.
I don't know much about electronics, and watching your videos reminds me how much stuff I don't know. Always enjoy your videos.
It’s fun, you learn a little about how our gear works.
Sounded great with your first play, lovely and jangly with a beautiful bottom, just like a Fender Twin should sound.
Lovely approach , on the other tech , as a player , I take same approach , constructive not destructive .I always learn even in the most unlikely situation .,,,,,Now back to business , lol , love the systematic approach to said issue , ..Cheers
Your videos should be required viewing for Fender amps, as important as the booklet/ manual that we all ought to read. It can take a life-time of trial and error and evening classes to learn that the various layouts and how/why they work. The BMT tone stack is worth a video or 2 to help users understand why the amp reacts as it does. Thanks, great video .
Really like all you videos. Your very good at explaining everything to anyone, and have a great demenor and don't waste anyone's time. Thanks brother.
The silicon under the dog house cover may have been to minimize any transformer vibrations.
Nice to see you back.
Great video - I'm working on my own TR and have a question - is the heater fuse @ XF2 unnecessary? I see with the mod it is no longer in the circuit. I'm also assuming that the black/white heater wires from the board could be removed.
I've got a client who writes pin numbers around the tube sockets, too.
Drives me nuts
The silicone on the doghouse might have been to keep it from buzzing or rattling.
Yeah except they don’t do that. It’s really not an issue with these.
Awesome man 👍
A customer just dropped one off to me that blew the fuse because someone shot the power transformer on the utility pole at the party he was playing. Took out two of the tubes as well, they blew my multimeter fuse and my BK auto transformer fuse.
Shot the transformer with a gun???
@@enricopallazzo2987Yes, Chicago's west side parties are no joke.
@@vintagetubeamplifiers good lord I was hoping that was a typo
@@vintagetubeamplifiersSo it was a power surge from... why tf wd someone shoot a transformer on a pole!?! Cowboys!
Edit: us Aussies usually drink at parties... but we're a bit weird!
When those transformers short it sounded like a huge explosion. Apparently someone wanted to end the party.
When you let an amp run after repairs/mods, in this vid you mentioned 12 hrs, do you leave it in stand-by or just turn the volume down and leave it in play and check on it later?
12 hours of playing a loop into a dummy load and I can hear the output of the dummy load through a Redbox cab simulator - I check that sporadically through the 12 hours.
Great question
I can deal with the PCB instead eyelet main board but believe the amp would be better served without the front control board and done in old school fashion. Am I wrong or splitting hairs on this?
Absolutely in agreement with you.
"If it ain't broke..." 😉
The board mounted pots and jacks are not bad, if the solder joints are checked occasionally. The pots are good quality and the circuit sounds good with this setup. And they’re consistent and lower the cost for the buyer.
I guess I’m saying, “Are they ideal? No. But are they detrimental? Also no.”
I agree.
Do the original versions of this Twin Reverb always have PCBs like this "reissue"? BTW I had a 100watt twin many years ago as my first "real" amp and when I had the volume on 2 all if the plates, dishes etc stored in a big antique dresser in the dining room next door would shake and rattle when you strummed a chord! Great clean sound though😁
No, they were properly built.
Nice job but I am inquisitive of why you went with black and white wires in-lieu of green for the heaters?
The B&W heater wires are stock. But I often do that in my own builds to keep track of which side is which.
If it only it was feasible for you to look at my Blues Deluxe. Sound goes out but power is still on.
See my Blues and HRD playlist. Lots of fixes there.
Could someone have used silicon under the dog house cover due to a rattle? I've never heard of it before but it's one of the only logical things I could come up with.
Unsolved mystery. We will never know. ha
Solving a non-existent problem is my guess.
Youve worked on alot of amps, what your favorite speaker brand and type. For blues and midgain stuff. Im struggle finding a speaker i like for prs hdrx20 amp. Ive tried 1 x12 2x12 1x 10 2 x10 of alnico and afew ceramics. But i havent found the right speaker yet. I build my amps around a speaker or set of speakers, that how i know what caps and resistors to use in the tone stack. Since i didnt build this i cant find the perfect speaker. Wondered your op.
WGS ET65 or Celestion Creamback 65.
"Nashville beer bike bridezilla things" lmao.
Silicone was probably to keep the doghouse from rattling
How often do you find yourself in this position? The tech before you did a good job, but the customer is super picky and wants something done better than is reasonable? I ask because I expect to encounter people like this once I start servicing amps and I'm not sure how to deal with them.
Not quite that drastic. Customer had work done by a different tech, amp didn’t work when he got it back, he was worried and brought it to me.
I was able to reassure the customer.
But it was a very reasonable thing to do - most owners wouldn’t know if a tech did something wrong - they only know if it doesn’t work or is noisy etc.
If you want to do this professionally, I guess the lesson I’d want you to take away is it’s ok to say “the competition” did good work. Don’t find “fault” just to prop yourself up.
I’m glad this guy is doing good work - I’m already slammed and have to turn work away. Good to know I can recommend him in the future.
If he sees this video, he’ll feel good about it. And if he didn’t know about the heater and thermistor issues, he does now. So even better. For everyone.
Did you crank it up to see if higher volume levels had anything to do with it squealing?
Of course not. I’ve never worked on an amp before.
@@PsionicAudio sorry, I didn't mean it like that. You just didn't crank it in the video...
I gotcha, no biggie. I test at all levels, but the loudest levels aren’t bench video friendly.
Not quite related, but is 6l6gc swappable with kt66? planning to change the tubes of my Fender Deville
Yes but I wouldn’t recommend KT66s in a Deville - it can barely handle the heat/current of 6L6GCs.
@@PsionicAudio what's the best tube I can put in my deville? any suggestion?
After owning quite a few different brands amps I can honestly say the Fender board in this build is of the cheaper variety. With cheap components comes problems even in good designs. Ymmv.
You mentioned a bad/weak ground could cause the mids to go crazy with the 100k pot. Why isn't what the owner heard a normal function of the 100k pot, turned up, lifting the tone stack from the path? David Allen (and perhaps others) calls that a "raw" control and the 100k pot mod is intended to make a Fender amp sound more "tweedish" (which I personally don't care for). On the other hand, when you turned the mids all the way up, it did not have that characteristic. May have missed something, but, as the curious owner of a Sweet Spot, I have to ask. Thanks
How much gain the 100K adds on full depends on the volume setting. It doesn’t work like an overdrive itself.
The Fender TMB tone stack is considered "lossy." e.g. it send a lot of the audio signal to ground. Those "raw" controls increase the tone stacks resistance to ground, thus retaining more (sometimes much more) of the gain from prior amp stages. If subsequent amp stages (e.g. reverb) are not designed to accommodate that sort of signal level then you can get all sorts of unpleasant behavior including oscillation. Even worse might by the sorts of things you dont hear, but can pose a long term risk to your amp's health.
@@PsionicAudio That makes sense. Thanks. I wonder now if the owner's observation didn't coincide with added/excess mids at higher volume, and he didn't like the result, thinking it a defect.
@@ThomasD66 That, also, makes sense. It's the excess preamp gain from the 100k pot (turned up, at higher volume) that creates the sound I don't care for. Doesn't sound like drive, breakup, what have you, to me. Just doesn't sound good to me (and, perhaps, to the owner of this Twin), though I understand many like it just fine.
Nah, he said both channels were really loud and distorted and the reverb squealed. I’ve moved wires and tapped on everything, can’t replicate.
But at least he knows the tech he used did a good job.
No. The computer designer who built it in the first place, messed it up.