High gain, dual channel, 60 Watt amp design and build thread

Paolo_M

Lads,

I'm a good way into this project already but I thought you might to check out the progress.

If anyones interested I'm happy to discuss any part of the design and build.


The features list is:

Two channel; clean and high gain, independent gain, tone stack and volume control for each.
Tone stack mode switch; american and british voicing for each channel.
Upper mid boost switch for the high gain channel.
Gain boost switch for clean channel to give a "crunch" type tone.
The high gain channel is modelled after a 5150/Dual Rectifier/Soldano SLO.
The clean channel is modelled after a Blackface Fender or Mesa Lonestar.
The channel switch is foot-switchable.
There is also a foot-switchable volume boost for solos.
There's master resonance and presence controls.
There's a series FX Loop.

The power amp can take EL34/6L6/KT88/KT77/6V6 etc. power valves.
There's a vintage/modern switch. Vintage give a loose saggy kind of response and modern gives a tight and aggressive response.
There's a choke switch so that you switch between choke and resistor modes. The choke is a popular 5150 mod and this lets you switch between before and after.
Finally there's a ground lift switch to prevent ground loops when using FX in the loop.

Here's the schematics. They've changed a bit since I drew up these but you'll get the idea.




Here's the first delivery of stuff.




I'm using hammond transformers and I'm well impressed with them. Here is the output transformer compared to a DSL I fixing up. My OT is rated for 60Watts and it's a 100 Watt DSL.





Here the chasis drilled, painted and laquored.

Paolo_M

Power transformer installed.




Boards installed to see what they look like.




Power amp board stuffed and soldered.




Transformer, filter caps, choke and valve sockets all installed.




Heater wiring.




I've actually finished wiring the dirty channel but haven't taken progress pics yet but, even better, here's the first sound clip.
It's recorded with a digital camera late last night at really low volume but you hopefully get the idea. I'll be making proper clips with SM57 -> ProTools soon though.

I originally designed it to be 60 Watts but I lowered the B+ so that I could also use 6V6s and so I was limited to 50 Watts maximum clean power.
Check out my blue LEDs!! The power and stand-by are what you see here but there will also be channel status and solo boost status blue LEDs when I'm finished.
It's gonna be an visual and oral assault when I'm done!!

https://www.youtube.com/watch?v=mSdXtThkHDc

eoin5

Plenty of balls in that!

68 lost souls

Looks great. From your description of the sound and options your looking for it is the exact amp Im looking for :P Great to see your work again. Im hoping to build a few amps soon. Just did the Madamp G2 a few months ago and was going to build an AX84.com amp of some sort next. Where did you source all your parts?

What speakers are you playing that through. Nice sound even if it is coming through the videocamera mic. I reckon the next recording will be great. What sort of setting was the recording at i.e. gain all the way or midway/ mid boost on or off ?

Paolo_M

Thanks lads,


68, I'm running it through a 2 X 12 loaded with a V30 and G12H.
Looking forward to seeing and hearing some of your stuff.
I get my parts from Tube Town.


Here's a new clip showing the American/British voicing.
Gain is about 6/7, master volume @ .5, yup that's my picking you're hearing.
I'll probably have a free house on Thursday to do some proper recording.

Lemme know whatcha think tone-wise so far please. Sometimes it hard to be objective when your working on something so long so input is appreciated.
Obviously this is the falt brootz tones I'm going for here!

https://www.youtube.com/watch?v=9RiNRg5Mq7E

68 lost souls

Sounds great. The fist sectionsounds like a great amp for lead, nice high end cutting through. It is very similar to the 5150 at that point, I reckon I might actually prefer yours for that sound.

The bottom end growling setting im imagining where you are looking for the mesa sound? To me personally I feel like it needs a more compressed sound or something there, maybe some more low mids or something but Im sure its very hard to get with the broad range you have. From bout 2:40 in this video is what I like on a dual rec but then again that is a personal thing and is what I look for but it may not be what you want.

Apart from that you have yourself a kick ass amp. Nice job.

https://www.youtube.com/watch?v=It_k4uDnetU

68 lost souls

Any plans on selling these as botique amps or are you just doing it for yourself?

Paolo_M

68 lost souls wrote: »

Any plans on selling these as botique amps or are you just doing it for yourself?

The guy in the Mesa video does like saying "gain saturation" doesn't he!!

I'm hearing you regarding the low mids rhythm vs upper mids solo tone.
The vid was only quick and I just dialed in a sort of 5150 tone. There's much more low mids there if dialed in. The resonance was at 3 (presence 6) and the bass at 4 if I remember rightly.
The Dual Rec has a kind of nasally growl that I love one day and hate the next. This is from a certain circuit element (namely feedback going right into the tone stack) that I eventually decided not to emulate. In the end my preference between the two amps is with the 5150/SLO/hot-rodded JCM800 type tone. Other amps I'm thinking of are channel 3 of the Diezel VH4 and some of the Bogners. I'll bet you'd prefer the Diezel Herbert though?

My intention once I get the project finished will be to dial the amp for 5150(ish) tone and use the MXR 108 to get to get more chunky lower midz when needed.


I've no intentions of selling any in the near future anyway. The intention is to do some serious guitar playing for a few months once the amp is finished and tested.

Knifey Spoony

That sounds unreal man. Currently starting my first diy pedal. It's just a simple boost pedal (have to start somewhere), with a vacuum tube at it's heart, so most of this is still a bit over my head but hope to work up to building my own amp one day.

Good luck with the rest of the build.

68 lost souls

Yeah I think I do prefer the Herbert alright :P The 5150 settings is dialed pretty good already. I get what you mean about the Dual Rec though, some days I want to sell all my gear and buy it, other days I prefer the sound of my Marshall G215 :P depends on the mood really. It really is a love it or hate it amp.

Looking forward to seeing the end product when its all done. Are you putting it in a headshell or leaving it in just the chasis?

Paolo_M

Knifey Spoony wrote: »

That sounds unreal man. Currently starting my first diy pedal. It's just a simple boost pedal (have to start somewhere), with a vacuum tube at it's heart, so most of this is still a bit over my head but hope to work up to building my own amp one day.

Good luck with the rest of the build.

Cheers, sounds like a cool a cool first build. Is it gonna be like the HT pedal?

68 lost souls wrote: »

Yeah I think I do prefer the Herbert alright :P The 5150 settings is dialed pretty good already. I get what you mean about the Dual Rec though, some days I want to sell all my gear and buy it, other days I prefer the sound of my Marshall G215 :P depends on the mood really. It really is a love it or hate it amp.

Looking forward to seeing the end product when its all done. Are you putting it in a headshell or leaving it in just the chasis?

Well it's done, as in finished and everything working.
Months of tone tweaking ahead no doubt. :rolleyes:
Yup, the headshell is on order but will be two weeks so I can't take it to rehearsal for testing. :mad:

Here's a quick of the functions on the amp.
I recorded this at reasonable volume with my digi cam so it clips a lot and compresses quite a bit too but you should get the idea function wise.

https://www.youtube.com/watch?v=3GSw3vt823k

Lemme know whatcha think.
I've dialed in a pretty Fendery, glassy clean and a brootz type dirty.
That's my squire with humbucker bridge and it's tuned to D.

Are the blue LEDs too much? They don't glare like that it the room obviously.
Channel switching noise and general noise levels I'm happy with.
Any other thoughts?

I'll make proper recordings later in the week with a 57 and protools.
Probably take the form of a blues type example, trash example and so on.

Knifey Spoony

Wow, that is pretty impressive sounding. Loving the dirty channel, git's got some bite to it.

Paolo_M wrote: »

Cheers, sounds like a cool a cool first build. Is it gonna be like the HT pedal?

HT? Hight tension? Nah, it's gonna be run off a 9v to 12v DC adapter, which I think means that the tube would then be in straved cathode mode. Just following a schematic in the link below, just to get a grounding in working with tubes. Have a plans to then design my own tube distortion pedal, so should be a fun summer of soldering and debugging circuits.:p

http://www.instructables.com/id/The-ValveLiTzer-Low-voltage-Tube-Booster/

Paolo_M

Knifey Spoony wrote: »

Wow, that is pretty impressive sounding. Loving the dirty channel, git's got some bite to it.



HT? Hight tension? Nah, it's gonna be run off a 9v to 12v DC adapter, which I think means that the tube would then be in straved cathode mode. Just following a schematic in the link below, just to get a grounding in working with tubes. Have a plans to then design my own tube distortion pedal, so should be a fun summer of soldering and debugging circuits.:p

http://www.instructables.com/id/The-ValveLiTzer-Low-voltage-Tube-Booster/

Cool, the HT I meant is this
HT pedal.


Here's my latest soundclip.
I'm going for more "classic" tones here.
I'm using my Les Paul in standard tuning, there's a carbon copy and MXR EQ in the loop and a boss OD up front.

68 Lost souls, I set up the EQ to do more of that Mesa tone. It's pushed @ 120Hz, scooped a little @ 500 and 1k and pushed a little @ 6k and 8k for that snarl.

Again it's low volume digital camera but I will definitely be making miked clips next week.

https://www.youtube.com/watch?v=TH37ZstzXnU

Let me know whatcha think tone wise.

Niiice, dude..
:cool:

Paolo_M

Deleted User wrote: »

Niiice, dude..
:cool:

Cheers.

Here's a link to sound-click where I've uploaded a few miked up tone clips.

http://www.soundclick.com/bands/default.cfm?bandID=1067692

There's some clean, OD and heavier tones.
I'm use my Les Paul throughout.
Everything is recorded straight with SM57 => MBox => ProTools LE and there's a touch of reverb on each track.
My recording skills aren't great but you should get the picture.

Again input, thoughts and criticisms would be appreciated.

darrenw5094

Paolo_M wrote: »

Cheers.

Here's a link to sound-click where I've uploaded a few miked up tone clips.

http://www.soundclick.com/bands/default.cfm?bandID=1067692

There's some clean, OD and heavier tones.
I'm use my Les Paul throughout.
Everything is recorded straight with SM57 => MBox => ProTools LE and there's a touch of reverb on each track.
My recording skills aren't great but you should get the picture.

Again input, thoughts and criticisms would be appreciated.

Those clips are savage.........

universe777

Amazing tone, wow!! Did you design it yourself or is it a kit?
Will you be making them to sell?? How much?

Paolo_M

darrenw5094 wrote: »

Those clips are savage.........

Cheers mate.

universe777 wrote: »

Amazing tone, wow!! Did you design it yourself or is it a kit?
Will you be making them to sell?? How much?

It's my own design, though the OD channel is heavily influenced by the SLO preamp. It's been tweaked a fair bit to my taste. A couple of the other features are entirely my own (the "choke" switch and the power supply mode), and not on any current production amp AFAIK.
Hadn't any plans to build any more or sell any, though you never know...:)

shizz

Paolo is this a modified version of the last amp you made or is it completley new?