I like to mark knob positions if I find a setting that works. I know different venues settings have to get tweaked to fit the room. I like adjustability but I also know knobs get bumped around. That's why a quick visual conformation can be made with marks. But to each his own.
If it's for FOH, then the volume is controlled by the console. Usually the power amps are set to their highest volume/gain before they start to generate noise. On a well designed amp, that's all the way up! I didn't realize Marshall made power amps like this... Kinda cool to see the guts vs the old crown macrotechs and the infamous Peavey CS series amps.
Looks like the bias circuit uses a couple axial caps instead of the box cap like the jcm900s do? Also is it just me or did the 5w resistors on the right side get a little toasty? Faint darkening in the middle I’m not seeing in the left side. Could just be camera angle
Still has the capacitor derived bias circuit like the 900, sadly. And you have good eyes - I didn't mention it as I tend to replace screen grids anyway. 5W low mass Vishays will be going in.
I had two of them dying and even though very good and neutral sounding I gave up on them ... Just used the two Drake transformers - one to get a kind of JMP 50 build by a boutique Amp builder Peter Linneman - the other to reduce the price for that
Easy, and easily reversible solution: Move the knobs to where you like them. Place a small dab of silicon RTV on each knob perimeter, so it's also contacting the panel. Wait 30 minutes. Done.
@@PsionicAudio , 4" in CT, and -1 this morning, but my brother in Baton Rouge said they got 6 to 8" in his area. I saw a photo of a snow sculpture of a gigantic crayfish! The snow and freezing temps in FL is gonna drive up the price of orange juice....
Interesting! I am not that familiar with stereo power amps so this this will be interesting to follow. Hope you're dealing with the big chill in Memphis ok. Have you seen the images of people snow skiing in the French Quarter in NOLA?
My brother in Baton Rouge sent me a photo of a gigantic snow sculpture of a crayfish. They got 6 to 8" where he lives! Only 4" in my area of CT, but it was -1 this morning.
That's why you always keep an extra knob connected to nothing. Mine was labeled "blow me" I would go turn it a little and EVERY time they would say "ah, much better"😅
@@DetroitWrecker666 , there was a session player who had a switch like that on his guitar, which did absolutely nothing, nada, zip, zilch. ( bassist Lee Sklar, perhaps, or somebody he worked with?)
Probably just to simplify setup and ensure matching per channel. But it's not my place to tell owners what to do, so long as it's safe for the circuit and does not damage the value of the device.
Can he just not mark where he likes the knobs and get on enjoying life? Why go through the extra expense and lost resale value OR spending more money to revert it back to stock.
I'm the guy who vented about tube testers a couple of years ago. I have since learned quite a bit from your channel. I would admit to being a fan if you stopped playing "that" lick :)
The anti-AxeFX
POWAH!
Always a practical approach. Not sure why someone would want to eliminate volume pot. To each his own.
The more controls you have, the more opportunity for it to be set wrong. You're limiting what Murphy can do.
@@russellhltn1396 interesting take...
Yeah, I'm thinking just don't move them. How hard is that?
I like to mark knob positions if I find a setting that works. I know different venues settings have to get tweaked to fit the room. I like adjustability but I also know knobs get bumped around. That's why a quick visual conformation can be made with marks. But to each his own.
If it's for FOH, then the volume is controlled by the console. Usually the power amps are set to their highest volume/gain before they start to generate noise. On a well designed amp, that's all the way up! I didn't realize Marshall made power amps like this... Kinda cool to see the guts vs the old crown macrotechs and the infamous Peavey CS series amps.
Looks like the bias circuit uses a couple axial caps instead of the box cap like the jcm900s do? Also is it just me or did the 5w resistors on the right side get a little toasty? Faint darkening in the middle I’m not seeing in the left side. Could just be camera angle
Still has the capacitor derived bias circuit like the 900, sadly. And you have good eyes - I didn't mention it as I tend to replace screen grids anyway. 5W low mass Vishays will be going in.
I had two of them dying and even though very good and neutral sounding I gave up on them ... Just used the two Drake transformers - one to get a kind of JMP 50 build by a boutique Amp builder Peter Linneman - the other to reduce the price for that
Lyle, I have a all original 1965 Pro Reverb that I would like to bring in to get serviced. What is the process?
Mahalo Lyle!
Easy, and easily reversible solution: Move the knobs to where you like them. Place a small dab of silicon RTV on each knob perimeter, so it's also contacting the panel. Wait 30 minutes. Done.
The tone of your voice says so much in this video vs another recent posting. 😃😒
All I heard him say was, “Glad it’s not a Mesa, glad it’s not a Mesa, glad it’s not a Mesa…”
Good morning, Lyle! DSM, IA got a dusting of snow overnight, but the temps are soaring into the low 30's today!
Same here! I may wear shorts...
Lucky you, I was at -9f this morning
-4 here in Detroit this morning
7 inches of snow in the low 30’s here in Long Beach Mississippi
@@PsionicAudio , 4" in CT, and -1 this morning, but my brother in Baton Rouge said they got 6 to 8" in his area. I saw a photo of a snow sculpture of a gigantic crayfish! The snow and freezing temps in FL is gonna drive up the price of orange juice....
Fixed pot value? Hey Lyle, is there any way you can modify my amps to the exact right values that make me play better?
I need a copy also 🤣🤣
Hey Lyle- I try and watch all your podcasts, and not sure if you’ve commented on them, but do you have any opinion on Winfield amps?
Thanks Travis. I don’t have any experience with, so no opinion of, Winfields.
Interesting! I am not that familiar with stereo power amps so this this will be interesting to follow.
Hope you're dealing with the big chill in Memphis ok. Have you seen the images of people snow skiing in the French Quarter in NOLA?
My brother in Baton Rouge sent me a photo of a gigantic snow sculpture of a crayfish. They got 6 to 8" where he lives! Only 4" in my area of CT, but it was -1 this morning.
Which brand new Fender amps can you recommend without having to buy a real vintage one from the 60's.
The 65 Reissue series
Can you a video on those two pots on the board? I know one is a bias, I don't understand the other one
One is for the overall bias level, and the other for the adjustment of the bias balance.
Nice
Painter’s tape across the knobs at their set points!?!? lol
Pros use gaffer tape. ;)
The fixed in place pots make sense to me, then I can honestly say: "that's as low as it goes".
That's why you always keep an extra knob connected to nothing. Mine was labeled "blow me" I would go turn it a little and EVERY time they would say "ah, much better"😅
@DetroitWrecker666 😆🤘!
@@DetroitWrecker666 , there was a session player who had a switch like that on his guitar, which did absolutely nothing, nada, zip, zilch. ( bassist Lee Sklar, perhaps, or somebody he worked with?)
Then it can’t go to 11.
@@goodun2974Yes Lees famous producers switch.
Why would an owner want to do away with the volume control and instead always have it on full / part volume ?
'Cause they like to party.
Probably just to simplify setup and ensure matching per channel. But it's not my place to tell owners what to do, so long as it's safe for the circuit and does not damage the value of the device.
@ Fair enough Lyle, but personally I’d have kept the volume control. You never know when you’re going to want to turn it up/ down 😉😉
Because it's really hard to turn a pot? Its absurd😂
@ I saw someone comment on a drone video once saying the music track was too loud. Almost every reply to him was, turn your volume down then 😂😂😂😂
Marshall Marshall Marshall! (Oh! My nose!)....
Can he just not mark where he likes the knobs and get on enjoying life? Why go through the extra expense and lost resale value OR spending more money to revert it back to stock.
I sure hope they removed the paint from under that star-ground with multiple solder lugs.....
Uh..Maze...Ing
I'm the guy who vented about tube testers a couple of years ago. I have since learned quite a bit from your channel. I would admit to being a fan if you stopped playing "that" lick :)
nah nah nu nu nah, x4.
after he went to all the trouble of copywriting it? No chance!
@@tedmich LOL's!
@@kindisc
Hear it in my head all day...accidently play it too...its having an impact on society.
Why the actual phuk would the guy want fixed positions for the gain and presence, makes zero sense.