update, kinda lengthy 

SO... after 4 hours of burn in time, and following bluesfendemanblues advice for tweaking the tone controls i am now in LOVE with the OD channel. So far i am doing low volume.  I plugged my sheraton in and turned my controls to :

clean volume 6 with bright on
deep on
mid boost on
rock

treble at 7
Middle at 2
Bass at 2

Drive at 9
OD Level at 1
Master at 1
Presence at 8
od trim at 11 o' clock
PAB boost on MEGA!!!

at these settings that OD channel came alive! Nice and dirty and gritty and shimmery, ALMOST fuzzy very groovy. Backing the drive off to around 5 yielded a sweet swinging sound.

The Mega PAB boost is quite the handy tool on the clean channel. setting the volume to around 6 and master to 2 (low volume) will give a nice clean sparkly Blackface tone. step on the mega PAB and a nice overdriven Blackface sound emerges .The Mega PAB boost on the OD channel is insane. very fuzzy sounding. Again this is at low volume.

Of course, without the Mega boost or in PAB at all he lead channel just sings and sings, even through my kinda flat speakers. Can't wait to get my can and load it with a Weber Blue Dog and a Weber Silver Dog!! 

I'm giddy, can ya tell? 

ironically i am listening to Larry Carlton and Lee Ritenour's joint album through my Bluesmaster at the moment (burning it in) adjusted the tone controls to those settings, and it sounded right somehow. there's alot to those specific tone settings, i think...

I've got NOS JAN Phillips 6L6WGB and just fired it up two hours ago...already think it was a great decision. Very clean and articulate. I biased em to 50ma, as recommended by thetubestore.com and they are amazing!

Finally got a chance to get the Bluemaster up and running today.
Current tube compliment:

3 x "Preferred Series" 7025 preamp tubes from thetubestore.com
2 x NOS JAN Phillips 6L6WGB again, from thetubestore.com

Biased to 50ma (a lil hot, but recommended for these particular old stubby power tubes)

So far I am in LOVE with the clean channel. It is everything i hoped it would be and more. Proper Fender Blackface tone and then some. Very nice tonal dynamics and harmonics, with a nice crisp bottom end, even more so with the Deep switch engaged. I really dig the Jazz setting, adds a nice dimension to the clean side. My Deep switch was not wired properly but that's no biggie. All controls on the amp are functioning. I'm not in love with the Overdrive channel just yet, but i think there are a few factors for that:

1. The amp isn't quite burned in yet. Currently burning it in with all my jazz content on my ipod, the amp is actually sounding better by the minute
2. I have the amp running into my 20 year old 4x12 cab with my 20 year old eminence legend speakers, i think they may be a bit flat sounding for the HRM, i'm really starting to think speakers make all the difference on the OD sounds on the D-Style amps, i'm gonna try hooking into a couple of my combo amps and see what a difference it makes.
3. The preferred series just may not be aggressive enough or have the right tonal structure for the OD Channel. I also purchased a JJ 12ax7 that i may drop into V2 and see if it helps.

Don't get me wrong, the OD sounds great and can go from SRV type OD to fairly aggressive Marshall/Mesa type sounds depending on how ya rotate the OD trim knob, but it just sounds "flat" right now. I'm sure it will change as soon as the amp burns in a bit, and with some better speakers, and maybe with a change in V2..

as for the mods:
the 1/2 power option is pretty handy, as this lil bugger is loud, especially through a 4x12! i think it may be louder than my Sovtek, which is saying something. Dropping it down to 1/2 power takes some of the high end out, which is to be expected, but it doesn't suck all the tone out, which may be due the high bias i'm running, i dunno

The Mega PAB boost, is just what it sounds like, the PAB just more of it. kinda like hitting the Fat switch on a Fender Blues junior, but in a good way. it adds a lil more snarl to your town (think woman tone)

The SAG switch drops the current across the plates by about half or so, and warms the amp up quite a bit, and gives a little sponginess, as expected. It's a nice option to have if you normally run your tubes a lil hot like i do, and want a lil warmth for certain songs, and it can be switched on the fly, which is nice.

I really dig the amp so far, and the build quality couldn't be better. It is definitely not a plug in and go type amp, which is a good thing, it really allows you to find your own tone with all the various tone settings. I'm looking forward to getting it dialed in over the next few weeks (waiting for my 2x12 combo cab). Just gotta decide on speakers now. grrrr it's gonna be tough

Sounds like your tubes may have gotten damaged in shipping. Unforunately UPS is not as gentle as they could be...

i agree. If it sounds good, let it roll!!! 

they may have been biased at the factory, but it is conceivable that during shipping the tubes may have vibrated enough to make them drift, or the bias knob may have been bumped. it's easy to do, all you need is a digital multimeter. the instructions are on ceriatone's website

have you biased your tubes yet?

here's how nik wired mine...

Sduck:

Indeed there are a couple of a lil additions. Nik ended up using the ground switch for the half power, added the Mega PAB switch on the rear which switches between the the standard resistor and a 22M resistor, and added the sag resistor on the center tap and attached the switch to the bottom of the chassis. I put a few more pics on here to show those..

Today, the UPS man brought me a treat from Nik... He even sent a cool Tshirt!!!

thanks, guys! i didn't know gabkits would do custom jobs! 

This may have been asked before, but i could not find it on the board. Aside from building one yourself or having one custom made, does anyone know where to find a 2x12 cab for the overtone series, or know which fender cab, say from weber it would fit into properly? Thanks, and Happy Holidays!!

Got an email that my modded HRM Bluesmaster shipped today, about 3 weeks earlier than expected!!! 


Can't wait for it to get here. Guess i better order my tubes now!!

Hoffe,  It is indeed center tap between  the HT feeds coming out of the transformer (the 345 volt lines) that is used for the sag resistor. As far as value goes, i don't know as i haven't gotten the amp yet. Nik is setting mine up to use the ground switch to switch the resistor in an out of line.  Putting the resistor in my amp was actually Nik's idea. I had asked him if there was a way to add a tube rectifier and be able to switch between the tube and SS rectifier, but since there is no 5 volt tap coming out of the transformer used in the overtone series, it isn't possible.

hope this helps!

and sduck, didn't you build your HRM? That makes you WAY more qualified than me!