Do you guys leave your back panel on?

Myopic Void · Post by **Myopic Void** » Tue Dec 11, 2007 4:12 pm

Bluesgeetar wrote:+1!!! I whole heartedly agree! If Page does it then it is good enough for me! EVH doing it didn't have me sold but Page!!!! Yes! I see he also is using what seems to be 4 Orange or Matamps and 2 Marshalls and I can't make out what those other two are. The front panels go all the way across. But I do see those 100watt plexi Marshalls on tope of the Zoso cab. The one on top is a 67 or 68 with a laydown and the power caps inside. I don't see the large electrolytic can setting next to the far end EL34. Can't see the other one setting behind the ECC83 either. Nice! But that don't mean nothing. Eric has a 69 with all the caps on top and he has dead on Page tone, best I ever heard other than Page. And he is using SD PUPS! Damn! Must be that U87!?

Thanks for the heads up!!! I cannot see the vid from this PC

...I can't wait to check out the backs myself later. What type of glass? Did the bottom amp have standup's and filters on the top? Sounds like the top is 67-68 from what you say since it mssing the filter caps. If it had filters and laydown, bulgin then we could be dealing with Euro export 69-70 era.

Eric has a 69 with all the caps on top and he has dead on Page tone, best I ever heard other than Page. And he is using SD PUPS! Damn! Must be that U87!?

Kind words thank you my friend

Cheers,

Eric

Myopic Void · Post by **Myopic Void** » Tue Dec 11, 2007 5:56 pm

Bluesgeetar wrote:+1!!! I whole heartedly agree! If Page does it then it is good enough for me! EVH doing it didn't have me sold but Page!!!! Yes! I see he also is using what seems to be 4 Orange or Matamps and 2 Marshalls and I can't make out what those other two are. The front panels go all the way across. But I do see those 100watt plexi Marshalls on tope of the Zoso cab. The one on top is a 67 or 68 with a laydown and the power caps inside. I don't see the large electrolytic can setting next to the far end EL34.

Can't see the other one setting behind the ECC83 either. Nice! But that don't mean nothing. Eric has a 69 with all the caps on top and he has dead on Page tone, best I ever heard other than Page. And he is using SD PUPS! Damn! Must be that U87!?

Pete----> I had a chance to look at it. Here is my theory until we get cleaner footage: 1. On my two 69 amps the OT Silver Bell is facing the output tubes if you are looking at it from the back like the camera was. 2. my 67 has the OT orientation the opposite, the bells are facing the sides of the headbox the iron which is really dark is facing the output tubes. In the shot you see the whole bell like you would on a 69 not a 67.

Next when I looked at my 69's from the angle of the camera shot in the footage the stand up PT has the bell ends facing the OT. From a distance at that angle in the video the darkness of the iron makes it hard to see the PT, so I can see how it is not as visible. The only thing that is strange... where is the filter cap on the end by the EL34? My 67 does in fact have a cap their as does my 69's. So could it be removed and placed inside?

Also notice the Peterson amp and the Marshall have tubes with silver bases? It clearer with the Peterson but the Marshall output tube bases look the same. They also really large looking? I ask this, what production tube has a silver bottoms? None of my EL34's do new or old. My KT88's do in fact have metal silver bottoms.
Makes me wonder.... Hmmmm

Based on this somewhat vague footage my guess is.... a 69 100w style layout with a filter cap relocated or hidden due to poor video transfer. Not a 67. I cannot wait to get my hands on better footage.

Cheers,

Eric

Cygnus_X-1 · Post by **Cygnus_X-1** » Wed Dec 12, 2007 8:19 pm

On my JTM-45 I used to keep the back panel off while I kept changing it between a JTM-45 and a JMP-50, but now I keep the back panel on. Now that you guys bring up removing the back panels to help dissipate heat, I think I might do it too, especially on my 100.

Quickdraw · Post by **Quickdraw** » Sat Dec 15, 2007 12:30 am

This is just too pretty for Jimmy to put a back on...

Joe Popp · Post by **Joe Popp** » Sun Dec 16, 2007 12:12 pm

NitroLiq:

Try one of these Wheeled head bags for NYC. Use mine all the time!

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NitroLiq · Post by **NitroLiq** » Sun Dec 16, 2007 2:54 pm

Nice bags, Joe...I'm just a cheap bastid!

Quickdraw wrote:This is just too pretty for Jimmy to put a back on...

KT66...huh. Thats the back of one of the Marshalls onstage at O2?! If so, pretty interesting.

I said it in the other thread but perhaps they put those plates on with the intent of auctioning the heads for the Ahmet charity sometime down the road. They aren't stupid and know how over-zealous some of their fans are

GUITARmole · Post by **GUITARmole** » Mon Dec 17, 2007 2:14 am

Does anyone know what those quarter turn locking-screw thingamajiggies are called? I was thinking it would be cool to put threaded inserts in the head box and use machine screws to avoid the stripping out of the cabinet wood caused by frequent tube swaps and mods. A quarter turn locking screw would be even better. FWIW, I might even go with industrial velcro...

NY Chief · Post by **NY Chief** » Mon Dec 17, 2007 2:58 pm

GUITARmole wrote:Does anyone know what those quarter turn locking-screw thingamajiggies are called? ...

Do you mean Dzus fasteners?

Tone_Chaser · Post by **Tone_Chaser** » Tue Jan 08, 2008 12:07 am

I remember reading that Eddie left his off because of heat dissipation and that he was re-tubing constantly because of the Variac.

twinrider1 · Post by **twinrider1** » Tue Jan 08, 2008 9:51 am

GUITARmole wrote:Does anyone know what those quarter turn locking-screw thingamajiggies are called? I was thinking it would be cool to put threaded inserts in the head box and use machine screws to avoid the stripping out of the cabinet wood caused by frequent tube swaps and mods. A quarter turn locking screw would be even better. FWIW, I might even go with industrial velcro...

Yep, NYChief is right dzus fasteners. I've thought about that too. I'm familiar with them for holding on motorcycle body panels, but they seemed too big for an amp. And I wonder if they'd vibrate.

It's a great idea though.

Bunnest · Post by **Bunnest** » Wed Jan 16, 2008 5:17 pm

Here some food for thought. I left my '72 on overnight the other night, always keeping the backs off, so 8 hours later I discover it on, and for fun to hear the sound after so much warm up time, I played it, sounded unbelievable! Now I leave the backs ON to get the temp up just enough. I think that is the way the amp performs best, staying hot enought to rock, but ventilatted enough to stay within heat spec. Jim Marshall is a genius, leave the amp backs on, per design spec! I heard a big difference once it got really heated up, now I notice it sounds that good after a 1/2 hour WITH THE BACKS ON!!!

mayrandp · Post by **mayrandp** » Thu Jan 17, 2008 4:24 pm

Bunnest wrote:Here some food for thought. I left my '72 on overnight the other night, always keeping the backs off, so 8 hours later I discover it on, and for fun to hear the sound after so much warm up time, I played it, sounded unbelievable! Now I leave the backs ON to get the temp up just enough. I think that is the way the amp performs best, staying hot enought to rock, but ventilatted enough to stay within heat spec. Jim Marshall is a genius, leave the amp backs on, per design spec! I heard a big difference once it got really heated up, now I notice it sounds that good after a 1/2 hour WITH THE BACKS ON!!!

Interesting.

I leave my back panel on mainly to avoid that my kids poke inside the amp.

NY Chief · Post by **NY Chief** » Fri Jan 18, 2008 10:26 am

NitroLiq wrote:...small collapsable handcart and dragging it through subway terminals.

That's gotta be a pain in the ass, Pete! I don't miss that.

NitroLiq · Post by **NitroLiq** » Fri Jan 18, 2008 10:54 am

It makes every ampfest an adventure.

rgalpin · Post by **rgalpin** » Fri Jan 18, 2008 12:30 pm

mayrandp wrote: I leave my back panel on mainly to avoid that my kids poke inside the amp.

yeah ... kids ... roadies ... small rodents.

(please excuse any perceived redundancy)

Metropoulos Forum

Do you guys leave your back panel on?

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