2 builds going - 1 close to power up

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mat
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Re: Amp one - tweaked and done!

Post by mat »

stelligan wrote:
mat wrote:Really nice tone, congrats ! The amp looks also superb 8) What grill cloth is that ?
Thanks mat! That clip is actually from before I discovered a bad power tube. I wish I would have recorded after I replaced them. Sounded very much better then.
I had that cabinet built long ago, but asked them to send me enough for a future head cab. "bronze basket" is what I think they called it. The cab is from Stagecraft. An offshoot of Reason amps, I think. The link to the cab and cloth is here: http://www.stagecraftgear.com/servlet/t ... %93/Detail

I have not been able to source the cloth elsewhere. They may be able to help. A nice bunch of guys.
Stelligan, thanks for the link !
mat
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stelligan
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It's ALIVE!!!!

Post by stelligan »

Build #2 is up and running today. This morning's power up went without smoke. This started as a Bluesmaster, but ended up as a 6L6 183 with feedback at V1 and 120pf snubbers on V2(split the difference between 102 & 183 - it's all I had around). As usual, a few sniggles to deal with:

Didn't have an FET section in this and didn't know about having a resistor at the power supply to compensate so, voltages were a hair high at b+5. Henry helped me out on that one. Started with a 150k and ended up with a 220k to ground there.

I didn't realize I had an on-off-on at the rock/jazz switch.... That works a bit funky.

Missed a connection at the presence circuit at the 390 resistor.

After dealing with that, it works great and sounds killer. I have to work up some tunes for rehearsal tomorrow and spent way too much time with this today. Damn! There is a lot going on with a real deal build - and I didn't mess with an FET board. I have built quite a few modified D'Lites, but this 183 100 watter kicked my wiring ass......


To do:
Fix the Rock/Jazz switch, tweak the PI, mount a LNFB defeat switch at V1, I should do an FET section - just don't want another parts order, bolt it in the head cab.

I'd do some gut shots, but it pretty much looks like CHIP's & UHOP's on the inside :) . I'll get some clips up tomorrow after rehearsal.

Thanks again to everyone for all the help. Shad & Tony especially for the info and layout. Nice sounding circuit.
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Last edited by stelligan on Sun May 15, 2011 5:00 pm, edited 1 time in total.
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stelligan
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Still tweaking......

Post by stelligan »

Getting closer all the time. Switched PAB and R/J switch to latest 183 layout revision and liked the way it sounded as rev.10 better :? :?: Then wired it back....
No FET in this build so, there is now a Gil style tone cut pot living there(.0012uF cap & 1 meg pot). I do not need it with a d-lator in the loop, but when I don't want to haul the d-lator - it is a necessity for the OD with a Strat. Humbuckers and Teles I usually have it off or low.

A bunch of tube swapping over the last month. Electro Harmonix in V1, GE in V2(thanks Scott for the eBay dude), and Sovtek LPS in the PI.

Gettin' there - not there yet

Any ideas for:
1) PAB is a BIG jump
2) Still unsure that R/J switch is operating as should
- rock has more lows than jazz
- jazz is an anemic and unusable setting for me
Are these observations in line? First time I have had a build with this switch.

Thanks again for all the help, y'all!!
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bluesfendermanblues
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Re: Still tweaking......

Post by bluesfendermanblues »

stelligan wrote:Getting closer all the time. Switched PAB and R/J
Any ideas for:
1) PAB is a BIG jump
Great you have another nice amp!! 8)

PAB for starters try lowering 22M resistors to 4M7 or even lower.

OR If you prefer a less mid focused boost try Bill's (wjdunham) RAW BOOST mod:

.....re-wired the DPDT switch to
lift the mid pot with a 100K and
bass with a 220K.
.....works really well with a strat, really fattens up the OD, and will give the clean a nice edge without getting honky.


https://tubeamparchive.com/viewtopic.ph ... ht=pab+mod
Diva or not? - Respect for Mr. D's work....)
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Structo
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Re: 2 builds going - 1 close to power up

Post by Structo »

Yeah, the Preamp Boost is kind of a primitive boost.

It really depends where you have your tone controls set, the lower they are the bigger the boost will be.
If you have them at noon or above the PAB won't be as huge of a volume boost.

You can play with those resistor values, some guys put a pot on it.

Rock mode is bassier and gainier than Jazz mode so that is normal.
It's what that cap and resistor are doing in the Jazz setting that make it sound weak.
Tom

Don't let that smoke out!
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stelligan
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Re: Still tweaking......

Post by stelligan »

bluesfendermanblues wrote: Great you have another nice amp!! 8)

PAB for starters try lowering 22M resistors to 4M7 or even lower.

OR If you prefer a less mid focused boost try Bill's (wjdunham) RAW BOOST mod:

.....re-wired the DPDT switch to
lift the mid pot with a 100K and
bass with a 220K.
.....works really well with a strat, really fattens up the OD, and will give the clean a nice edge without getting honky.


https://tubeamparchive.com/viewtopic.ph ... ht=pab+mod
Thanks for the link and PAB ideas, bfmb. Sounds like a good plan.
It is sounding very good so far. I just need to get it all buttoned up.....
Structo wrote:Yeah, the Preamp Boost is kind of a primitive boost.

It really depends where you have your tone controls set, the lower they are the bigger the boost will be.
If you have them at noon or above the PAB won't be as huge of a volume boost.

You can play with those resistor values, some guys put a pot on it.

Rock mode is bassier and gainier than Jazz mode so that is normal.
It's what that cap and resistor are doing in the Jazz setting that make it sound weak.
Thanks, Tom. I wanted more confirmation of what I am hearing. I can way live without Jazz mode. Maybe a deep switch or alternate mid boost.
I just may use the j/r switch real estate for something other. Perhaps some mid cap monkey bidness.

Thanks guys!
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stelligan
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Re: 2 builds going - 1 close to power up

Post by stelligan »

4M7 at the PAB now. Love the mid boost on this build. I need to make it foot switchable, though.

Clip from this am. Mid boost on through clip:
http://www.luckystiffs.net/mercy183.mp3
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stelligan
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I guess I should take my lumps...

Post by stelligan »

I guess now that it is mostly done, I should bare the uglies. Here are the gut shots taken when I put the bleed control in and before I changed the PAB resistors. I find myself almost never using the bleed control. Possible that it's existence there bleeds some at full off??
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dcribbs1412
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Re: 2 builds going - 1 close to power up

Post by dcribbs1412 »

Congrats on a nice looking and sounding builds
did you get the mid boost foot switchable?

Thanks for sharing

Darin
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sonicmojo
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Re: 2 builds going - 1 close to power up

Post by sonicmojo »

Very nice! I love the cloth wire. I'm using some in my current build. Your clip sounds great. There is a 183 in my future.....
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Structo
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Re: 2 builds going - 1 close to power up

Post by Structo »

Looks good!

Is that a CE chassis?

The mounting nuts are different from mine.
Tom

Don't let that smoke out!
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stelligan
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Re: 2 builds going - 1 close to power up

Post by stelligan »

dcribbs1412 wrote:Congrats on a nice looking and sounding builds
did you get the mid boost foot switchable?

Thanks for sharing

Darin
Thanks, Darin. I have not done that yet. To be honest - I may leave it rather than try to cram another relay in there. I have a boost on my board that gooses the amp with out changing the tones so much.
sonicmojo wrote:Very nice! I love the cloth wire. I'm using some in my current build. Your clip sounds great. There is a 183 in my future.....
Thanks, man. I have a love/hate with that wire. Bought a bunch a long time ago and using it up. Hard to cut cleanly because it's that stuff with the pvc on the inside. I keep a nail clipper handy to trim the strays that happen. Looks like the old stuff, but isn't. I like that I can cram it against the chassis corners and it wont rattle like stiff teflon coated.
Structo wrote:Looks good!

Is that a CE chassis?

The mounting nuts are different from mine.
Thanks, Tom. That is a Funk chassis and OT iron. Magnetic components PT. Had it around a long time until I felt my hand was up to building again. My right hand and pliers still do not like each other.

I am finding myself contemplating selling this build to fuel another. It's kind of like the "thrill of the chase" thing. I enjoy the process more than the outcome. I own so many wonderful amps that I need for nothing. I do love the building/tweaking part more than the piling amps up in my studio part. Then - wondering which to take to a gig. I just have extremely mixed feelings about selling them for more than parts.........
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