I'm thinking about finally getting an OTS 50 but am confused as to which one...    They all sound great to me.  I really like the sound of spm72's FM100 (YouTube clips) but I don't plan to get an FX loop buffer (at least not for now).  Is the FM really that much brighter to compensate for the C-Lator?  Thanks.

Cool brah.  As for me it may be a looong time 'til I can afford one - and the Overtone Special's  the one I want.  Just sent in my $400 deposit for my daughters tuition for next year.  Hopefully Nik and Ceriatone will still be around when my kids graduate from college.       

marin,

I love how that singlecut's mid to high register notes sparkle but yet sustain on the verge of feedback.  And then the bass notes punch out.  For now, I have a very very very poor imitation of the OT Special using a Tonebone Classic pedal with either my Boogie MkII or my Blues Jr.  Lots of sustain but it just doesn't have that sparkle.   And the bass notes on my setup are a little flubby.    I'll just have to wait.   

Hi timeforheroes,

What kind of soldering tip are you using?  I prefer the conical pointed type.  First thing you should do to a new tip is to melt some solder with the tip and carefully roll it around so that it forms a thin layer - the process is called "tinning" and is supposed to help heat flow between the tip and the soldered joint.  Soldered joints should be at a good mechanical connection point.  So if you are trying to solder 2 wires together, the conductors should be twisted together first.  Proper technique is to twist both conductors - not one over the other.  If practical, apply the solder to the joint and then heat with the tip to melt - not on the tip and then drop it on the joint.  I know, sometimes this is impossible, especially if you are trying to replace a component.  A good resource for proper soldering techniques:

http://www.kpsec.freeuk.com/solder.htm

Cheers! 

Yeah, it's hard to believe that the holy grail "model"  of this vintage (80s? 90s?) actually has a solid state device in the preamp stage.  Look no further than the Boogie MkII for a Fetron device in V1 (that can be replaced with a warmer 12AX7).

When tube amps are cranked to their sweet spot, output transformers probably impart their own unique contribution to the sound coming out of the speakers.  Here's a nice article about Mercury Magnetics' OTs for Marshall original plexis and reissue plexis.  Sounds like they also make retrofit models for Fenderish amps as well.

http://www.legendarytones.com/guitouttrans.html

Mercury Magnetics:

http://www.mercurymagnetics.com/pages/mainframe.htm

I found a data sheet on the NTE452 JFET:

http://www.nteinc.com/specs/400to499/pdf/nte452.pdf

Happy reading. 

I found this site - http://www.blueguitar.org/ - with nice little amp circuits and mods.  It's not a Dumbleator but here's a simple active buffered FX loop mod one could probably easily implement:

http://www.blueguitar.org/new/schem/marshall/modnotes/ss_loop.gif

It uses a couple op amps, resistors, a pot, a couple capacitors and 2 DPDT switches.  There are also a few tube buffered FX loop mods on this site as well.  As with anything, your mileage may vary. 

A few toys lying around the house:

Ibanez RG560 and Les Paul Custom


Tweed Blues Jr.


Voodoo Strat


'62 RI Strat


Pedal Board


More Pedals


Marshall 1987X RI

Sami, marin, JeffreyB and Ah0bbs - you guys rock!  Your sound and viddy clips are why I want this amp.  Maybe I will get the kit version after all to save a few greenbacks.  Speaking of saving greenbacks, what do you all think about this 2x12 loaded Vox cab?

http://www.musiciansfriend.com/product/Vox-V212-2x12-Speaker-Cabinet?sku=609500

Ahhh, thank you! 

Good advice eri77.

I forgot to mention that a pair of needlenose pliers is also a good tool to have for amp projects.  And if you can find one of those spring-loaded de-solderers - that would be useful as well.

A few questions about the layout:

It looks pretty straightforward except fo the 3-pin devices labeled "5K" near wire B-25, "100K" near wire B-8, and "10K" on what looks like the "FET" daughter board.  Are these some kind of center-tapped resistor?  I've never seen something like that. 

Also, about the "FET" circuit.  Is the actual FET the grey blob in the middle of that daughter board?  If it is, I've never seen a 4-pin JFET or MOSFET like that.  I thought FETs are 3-port devices:  gate, drain and source. 

There are two connections to a "choke".  I'm assuming that the choke is an inductor mounted to the other side of the chassis as is the output transfomer.

I guess the "7812" is a 12 V voltage regulator device.

Just wondering.  If I can get these answers, maybe I'll actually feel inspired to CAD this as a circuit schematic in AutoCad.   

Hi - I'm a noob here too but I've done my fair share of electronic projects, but have not actually built a tube amp from scratch or a kit.  Looking at the ceriatone website, it seems that you can either buy all the parts in kit form (chassis, resistors, caps, trannies, pots, sockets and tubes - I think Nik uses JJs) and then have at it if you want to go that route.  Or you can substitute your own preferred components.  From my limited amp experience (rebiasing and replacing filter caps) you'll need at the minimum:

a soldering iron with solder
a wire cutter/stripper
a multi-meter (this helps, especially if you have a hard time reading resistor color codes)
screw driver
nut driver or adjustable wrench

I'm not good at wood-working so if you want to know about dove-tail joints on 3-ply birch cabinets and grill cloth installation, someone else here can probably help.   

Nik actually provides the component layout on the ceriatone website for each amp circuit.  If you're not familiar with amp circuits, it's a little tricky to figure out the connections to the output transformer secondary and primary so you should do a careful study of the circuit before you dig in.  You may want to get one of the many reference books out there like Aspen Pitman's Tube Amp book so that you can get acquainted with the basic topology of tube amps - from preamp tone stack to output tubes to DC rectifier-power supply to output transformer.  Always keep in mind that the typical power stage voltages are quite high and lethal - around 200 to 400 volts!  Once the amp is energized, the capacitors can hold charge even with the power off so that's another safety issue to be aware of.  When the amp is complete in terms of component installation, you'll have to adjust the bias to the output tubes if the amp is Class A/B push-pull.  Weber has a nice biasing tool that fits in the output tube socket and works with a multi-meter.  It's much simpler to bias this way than to use an oscilloscope to check crossover distortion levels.

Sounds daunting doesn't it?  Don't be discouraged - read up as much as you can on tube amps and learn simple electronic trouble-shooting techniques (e.g., how to read open and short-circuits, how to read voltage and resistances, etc.).  Also get that soldering iron and practice soldering.

Good luck and cheers!   

Count me in.  Glad I found it too.

Hey Eri77, this is totally unrelated to guitars and amps but as an electrician, you'll probably appreciate this.  I'm an engineer for our utility and we get a bunch of inquiries about "energy saver" black boxes for residential customers.  What they typically turn out to be are large capacitors mounted in enclosures (usually NEMA 1 - not even weatherproof).  Now it's true that there may be some power factor correction, but our tariff doesn't have a PF incentive built into residential rates - it just doesn't make economic sense.  There may be some I^2R wire loss savings as well, but this is typically pennies per month.  Let the buyer beware.