#1
I thought I'd have a go at building my own amplifier instead of going down the route of just buying the usual Marshall or what not. Now I've finished I thought I'd share some of the pictures of the build here and see what you thought. If you've got any ideas of how to improve it then please let me know. I'm always open to suggestions!





Last edited by Alasdair Davis at Aug 6, 2014,
#2
Version one of the internal components... it's had many changes since this. I just wasn't getting the high gain distortion sound I was after.



first thick vinyl layer going on to 4 X12. Had to remove speakers to create a nice finish.



Remaining thick vinyl layer going on. I chose to do it this way because it meant that if a panel was damaged instead of having to recover the whole amp/cab I can just replace the surface of a particular panel.

#3
with the new grill face, 3mm thick perforated aluminium powder coated black. You can see when I was doing this bit, Christmas... how time flies!



The fascia plate is 3mm aluminium also, lazer cut with a special vinyl print layer for the dials. This is also black powder coated. Gives a thick protective layer which is really durable and withstand a many knocks.



Aluminium edges added. These will take most of the bashing so instead of powder coating these have been anodised. they've been on for about 6 months now and they've weathered a lot of use really well. Anodising was definitely the right choice!

#4
Custom made corners. Couldn't find any off the shelf ones that would fit.... typical custom build I guess.





Starting to take shape...

#5
The finished article. 50 watt 2 channel amplifier head with 4X12 cabinet with Celestion vintage 30s.



At the famous Rockfield studios next to their amazing doors!



Being used by the legendary Robert Plant of Led Zeppelin at his home studio. I was very lucky to be able to take my amp to his studio and for him to use the amplifier. What an amazing place with so many gold records around the place. A true gentleman.

#6
Awesome. Absolutely awesome. Many congratulations!





By the way, do you have any video or audio clips?
Squier "VMC" Stratocaster
PRS SE Singlecut
tc electronic polytune
CMAT MODS Signa Drive
Blakemore Effects Deus Ex Machina
DIY gaussmarkov Dr. Boogey
EHX Small Clone
Mooer ShimVerb
DIY Beavis Devolt
T-REX Fuel Tank Chameleon
Ampeg GVT52-112
#8
ok, who let the guy that really knows what he is doing on here?

As if having a really nice finished product was not enough, you got feedback from one of the most important musicians ever.

that is just a great story. have you posted over on project guitar or anywhere else?
#9
Hi Rusty,

I've only posted here, is project guitar part of this forum or is it another forum? Thanks for the feedback. Really appreciated. Anyone who wants to come play the amp is welcome.
#10
Quote by Alasdair Davis
Hi Linkerman,

I have a video on youtube with some audio but the video is not great. I'm working on a better video at the moment with proper sound quality.

Thanks again

*youtube video*

Yep, the sound quality isn't the best, but the amp sounds really interesting.

I quite liked the cleans and I'd love to hear how it handles a drop-D or even drop-C tuned guitar while being pushed with a TS-style overdrive in front.
Squier "VMC" Stratocaster
PRS SE Singlecut
tc electronic polytune
CMAT MODS Signa Drive
Blakemore Effects Deus Ex Machina
DIY gaussmarkov Dr. Boogey
EHX Small Clone
Mooer ShimVerb
DIY Beavis Devolt
T-REX Fuel Tank Chameleon
Ampeg GVT52-112
#11
Well I'll make sure and include some heavier stuff in the demos I'm working on. Any particular songs you'd like to hear in the demo?
#12
Quote by Alasdair Davis
Well I'll make sure and include some heavier stuff in the demos I'm working on. Any particular songs you'd like to hear in the demo?

Since you're accepting requests, maybe a couple of riffs from Mastodon, The Black Dahlia Murder and Arch Enemy would be cool!
Squier "VMC" Stratocaster
PRS SE Singlecut
tc electronic polytune
CMAT MODS Signa Drive
Blakemore Effects Deus Ex Machina
DIY gaussmarkov Dr. Boogey
EHX Small Clone
Mooer ShimVerb
DIY Beavis Devolt
T-REX Fuel Tank Chameleon
Ampeg GVT52-112
#13
its another forum. they have more professional luthiers there. exploerbuiler posts on there alot. I lurk.

of course, if I built something that was played by robert plant, I would post it on knitting or gardening forums also.
#14
Mindblown. I had to triple check that I read "Robert Plant". It's a gorgeous amp, congrats on the build
#15
How deep is the 4x12?
It *looks* like you've got a second box constructed inside the first box -- how thick are the sides?
And what does it weigh?
How deep is it? I'm thinking that for lower end, you may have wanted it deeper...

One thing I notice that's missing is the piece that nearly all 4x12s have -- the chunk of 2x2, 2x4 or 4x4 that usually runs from the center of the speaker baffle to the center of the back panel. That's there for two reasons. At volume, you'll find that there's a particularly annoying resonance that happens at a particular note whose wavelength corresponds to a multiple of the diagonal of the back panel. The brace reduces the volume of this resonance and moves it up an octave or so. This was the original reason that Jim Marshall put that brace there, and that all 4x12s have them (the 4x12 was never really "designed"). The second reason is that 4x12s "oil can." The front baffle and the back panel actually move toward and away from each other (yes, even done in thick birch ply) in the lower frequencies. This robs the speakers of power and muddies the bottom end. The brace reduces oilcanning. The entire 4x12 cabinet is a kludge, but that's another story.

Suggestions for alternate finishing for future projects (rather than covering with vinyl and that relatively heavy edging material):

Modern Pro Audio systems are increasingly being coated with Duratex (available in a ton of colors). It's a rubberized , texturized tough stuff that won't rip (as do tolex/vinyls) and that's lighter than tolex. A pint of Duratex with a specialized roller will run about $17.95 from places like speakerhardware.com, and I think that Acrytech will send you a pair of rollers and enough Duratex for two coats (plus) for a large speaker cabinet for about $19.95.

I've taken speakers down to my local Line-X dealer and have had them shot with that stuff. It's spray-on pickup truck bed liner that goes on hot. Within a few minutes, you can take the cabinet home, and the stuff will continue to cure for a day or two (though you can handle it any way you want to). It's positively structural, even brutally strong. I later found out that the military uses it for the sides of buildings against explosions and as an anti-spalling protection. Note that not every truck bedliner product is Line-X. It comes in colors, and if you've got a number of cabinets, they'll order in a specific color for you. Check out the military videos on their website, and check out the Mythbusters YouTube episodes that feature this stuff.
#16
Quote by dspellman
How deep is the 4x12?
It *looks* like you've got a second box constructed inside the first box -- how thick are the sides?
And what does it weigh?
How deep is it? I'm thinking that for lower end, you may have wanted it deeper...

One thing I notice that's missing is the piece that nearly all 4x12s have -- the chunk of 2x2, 2x4 or 4x4 that usually runs from the center of the speaker baffle to the center of the back panel. That's there for two reasons. At volume, you'll find that there's a particularly annoying resonance that happens at a particular note whose wavelength corresponds to a multiple of the diagonal of the back panel. The brace reduces the volume of this resonance and moves it up an octave or so. This was the original reason that Jim Marshall put that brace there, and that all 4x12s have them (the 4x12 was never really "designed"). The second reason is that 4x12s "oil can." The front baffle and the back panel actually move toward and away from each other (yes, even done in thick birch ply) in the lower frequencies. This robs the speakers of power and muddies the bottom end. The brace reduces oilcanning. The entire 4x12 cabinet is a kludge, but that's another story.

Suggestions for alternate finishing for future projects (rather than covering with vinyl and that relatively heavy edging material):

Modern Pro Audio systems are increasingly being coated with Duratex (available in a ton of colors). It's a rubberized , texturized tough stuff that won't rip (as do tolex/vinyls) and that's lighter than tolex. A pint of Duratex with a specialized roller will run about $17.95 from places like speakerhardware.com, and I think that Acrytech will send you a pair of rollers and enough Duratex for two coats (plus) for a large speaker cabinet for about $19.95.

I've taken speakers down to my local Line-X dealer and have had them shot with that stuff. It's spray-on pickup truck bed liner that goes on hot. Within a few minutes, you can take the cabinet home, and the stuff will continue to cure for a day or two (though you can handle it any way you want to). It's positively structural, even brutally strong. I later found out that the military uses it for the sides of buildings against explosions and as an anti-spalling protection. Note that not every truck bedliner product is Line-X. It comes in colors, and if you've got a number of cabinets, they'll order in a specific color for you. Check out the military videos on their website, and check out the Mythbusters YouTube episodes that feature this stuff.



Hi, thanks for the message, some good points, I'd really appreciate the chance to speak via email. My email address is studio@davisamplification.com

- The 4X12 is just over 300mm deep which is a bit shallow but what I've done inside which you can't see as for some reason I don't have a photo of is each speaker has its own "chamber" which also gives it the strength that stops that resonance you were talking about. Next time I dismantle it I'll take a photo so you can see. The internal structure also has a handle which means you can remove all four speakers from inside in one go.

- The weight is 38 Kg so the same as an equivalent Marshall, it looks heavy because it is big but I spent a lot of money getting the strongest and lightest parts I could. All the metal is aluminium as well so I saved weight that way.

- Love the Duratex idea, I'm just working on my second amp now, same components but smaller and a lot lighter. (See design). Duratex would be just the trick as I've made a design that doesn't need protective edges.

Thanks again for the advice, it's really appreciated. As I said if you'd like to email me any more thoughts at all please do.

#17
You cant advertise here, or the MOD's will ban you. So you might want to remove that last post. You can advertise it in the classified section of UG

Other than that it is a cool project. Is that MDF you used? I'm not a fan of MDF because of the durability issue.
2002 PRS CE22
2013 G&L ASAT Deluxe
2009 Epiphone G-400 (SH-4)
Marshall JCM2000 DSL100
Krank 1980 Jr 20watt
Krank Rev 4x12 (eminence V12)
GFS Greenie/Digitech Bad Monkey
Morley Bad Horsie 2
MXR Smart Gate
#18
Quote by Robbgnarly
You cant advertise here, or the MOD's will ban you. So you might want to remove that last post. You can advertise it in the classified section of UG

Other than that it is a cool project. Is that MDF you used? I'm not a fan of MDF because of the durability issue.


Hey there, it's not MDF it's ULHDF which is a lot more durable... even more so than a lot of wood. Also I'm using a special glue that means that the screws are only taking about 40% of the strain. The amp has been used almost every day in different places and is still as tight as a nut.

I'm going to leave sell post up because it's only a minor post and the whole rest of the thread is nothing to do with selling it as I wasn't originally going to sell it.
#19
Quote by Alasdair Davis
Hey there, it's not MDF it's ULHDF which is a lot more durable... even more so than a lot of wood. Also I'm using a special glue that means that the screws are only taking about 40% of the strain. The amp has been used almost every day in different places and is still as tight as a nut.

I'm going to leave sell post up because it's only a minor post and the whole rest of the thread is nothing to do with selling it as I wasn't originally going to sell it.

While I appreciate your efforts in making an amp from the ground up, rules of this forum are rules. I was being nice twards you and trying to help you out, but since you won't remove that post.

Reported
2002 PRS CE22
2013 G&L ASAT Deluxe
2009 Epiphone G-400 (SH-4)
Marshall JCM2000 DSL100
Krank 1980 Jr 20watt
Krank Rev 4x12 (eminence V12)
GFS Greenie/Digitech Bad Monkey
Morley Bad Horsie 2
MXR Smart Gate
#20
Fabulous amp.
My son would like to build himself an amp like this with my help. Have you posted an instructable anywhere with step by step instructions, plus component list and schematic?
Would you be willing to do so?
Thanks
SurreyNick