After reading your last post, I diode tested the transistors and they seemed up to snuff. So I cleaned off the cooling fan, fastened everything down tight, and ran it. I had to keep the amp at sensible volumes, but nevertheless, I ran it for about an hour. I must say that thing is a beast. Punchy, defined, with gobs of power. At times, it seemed almost too punchy, too powerful ( if indeed, there is such a thing).
   Satisfied, I took the lid off and checked the resistor with the back of my finger. Barely warm! Maybe my original observation was a bit askew, or maybe the thermal management of the fan and heatsink made it a non issue. I'm going to take it  to a jam and see how she does.
    Roly, I'd like to thank you and all from the forum again for your help with this fault finding mission. I like to think I learned a little bit, and fear I have set on a new hobby to which my lovely ,understanding ,bride will be thrilled.

   I did some research and looked into the Long Tailed Pair circuit. I'm trying to get the gist with regards to what you said. I'm not sure what doesn't fit. Is it that I'm getting 40V difference at R317 ,or that if 2.67 mA are flowing through it,it should not be so hot.
 

   Heh heh, yes I hear ya. I metered all of the 2W resistors to find good values. R317 ,however, was super hot and was found with 83V and 43V on the legs relative to ground. This was at idle under full power and bias set.
   I reset the bias like you said. At idle btw the bases of Q309/310 I have 2.540V and trending down as it warmed up. Also, btw the TPs, I started at 24mV which dropped steadily to settle about 16 mV +/- 1mV.
   These measurements were taken over 30 min at idle. The components were slightly warm, except for R317 which was very hot.   
   Should I be concerned that this resistor got hot,or that the others did not?
   Does it seem like a lot of voltage on it?

  Thanks Roly,for the info. Your patience hasn't gone unnoticed or unappreciated.
  With that being said....
  I ran the amp at full mains ,only to have it overheat. After about 15 min, the protection relay clicked open, and the heatsink was hot to touch.
  I let it sit awhile and checked everything through the limiter.
   TP1 to G ~ 8.6 mV
   TP2 to G ~ 6.2 mV
   TP1 to TP2 ~ 2.6 mV
   Halfrail 6.6 mV
  I think these are good, yes?
  Then I disconnected the limiter and ran full, btw TPs it started at roughly 63mV and was rapidly rising. I shut er down without the other supporting measurements.
  So basically, the amp tests good under limited power, and drives hard on full.
As I'm writing this, l can't help but wonder if maybe R321 or R317 has gone bad. My thinking being, all values are good with the limiter providing the resistance needed. Take away the limiter....danger Will Robinson.
   

 

    I ran though it again to ,hopefully, get a different result. I ran the hartke through a 100W floodlight bulb, and into the 4x10 cab. For a signal, I have a Roland micro cube that has a tone gen. function. I plugged the signal into both the active and passive inputs on the head, both having the same result.
    Power on, fired up nice, circuit protection relay clicked closed.
    Again, bias started at 2.440V measured btw driver bases.
    At very low volume, situation normal; even signal, minor fluctuations of the bias voltage, limiter bulb holding steady.
    As volume increases; bias voltage drops sharply while my limiter bulb sympathetically, if not proportionately, gains briteness. As the tone decayed so did the bulbs britness to its steady low volume illumination.
    Needless to say, I'm reluctant to go full mains.
    Why does the bias drop like that with increased signal?
    You said the bias is a static setting, which i take to mean it is set  for the power amp to run most efficiently to amplify a signal, but with the signal effectively stealing voltage from this setting, how can the power amp be working sufficiently, let alone efficiently?
    Perhaps my apprehension is due to my inexperience, and if it is I do apologize.
Just trying to make sense of it all

   I checked the emitter resistors. This is what I found in mV:
     R325~ 14.4        R324~12.8
     R327~6.2           R326~8.6
     R329~ 5.3          R328~2.4
     R331~ 5.1          R330~10.2
   These were taken at idle,no load,no signal.
 
   In a previous post, I mentioned that a couple output transistors seemed warmer than others, almost hot. After some research, I found I should have fastened everything back to the heatsink. I have since done this.
   All is running well with bias voltage starting at 2.388V and after an hour at idle I'm at 2.350,with all hardware at even temperatures.
  Curious, I plugged the bass in and started thumping away. That is, signal in,no load and still watching my bias. With the volume up I noticed the bias Voltage jumping erraticly as I hit thee strings, sometimes going as low as .8V. Is that normal? Im hoping I stumbled across a normal audio phenomenon. What do you think?
   Still curious, I plugged into load. Sure enough, when the bais went below 2V or so, it resulted in crossover distortion. When I stopped playing the bias went back to a comfortable 2.343V. It went as far as opening the relay at a certain point. Where to look next?

  Hey everyone.I finally got my hands on the transistors I needed. After I found I had a faulty diode(D306), I checked transistors Q311,312 as Roly had suggested. I  found Q312 to be bad.
  I swapped the offending components and did some metering. Here's what I found
     TP1 to g~ 16.1 mV
     TP2 to g~  -1.5mV
     TP1 to TP2~  19.2 mV
     Halfrail ~ 9.8 mV
   V btw Q309 & 310 ~ 2.2 V   this varies with trimmer. This voltage trended down to     2.15V after a bit. That is to say, with thermistor 302 btw my fingers, and feeling the transistors for warmth. All ran well with Q314 & 319 getting warmest, almost hot.
   This was  all while plugged into my limiter lamp.
   From what was discussed in previous posts, the 2.2 V btw the bases of Q309 & 310 has me feeling optimistic. The other measurements, however, seem a little inconsistent with each other to my untrained eye. What do you think?
   

 I've got the new output transistor in, and everything powered up. When all said and done, all voltages are back to where they were previously. Except the halfrail voltage. That went up to 69.4mV.
  Satisfied, I checked the voltage across collector/emitter to find the same 1.8V. There was no change in value when adjusting the trimmer. While I had some downtime, I discovered a diode I believe faulty. It is the D306 diode off of the scheme,and it had a drop of .091V one way and .109V another. Pretty sure that's a no good. All other similar diodes had a drop of .581V one direction only. These were D303,304 and 305. It doesn't seem as though this would effect my cold bias problem does it? Seems more in line with my little blow out earlier.
 

   I'm fairly certain the other transistors are fine. I tested them out of circuit using the diode mode on my DMM. The respective output transistors were consistent with each other and the drivers checked out too. The funny thing is, the driver transistor I shorted across (Q310) is opposite the output transistor I found faulty (Q313). At least, I thought it odd. Is this cause for concern?
   

    I tested the driver and output transistors out of circuit as was described on page one of this thread. I found one of the output transistors (Q313 to be exact) to be faulty. I was unable to get an OL display on the meter in any combo of the leads. I have an exact replacement on order. Should I get a matched pair, or will just replacing the offending transistor be sufficient?

   I metered the voltage btw collecter and emitter of Q308 to be 1.9V. I metered btw Q309 and Q310 to be 1.8V.Then, I was going to meter btw bases of Q308 and Q310 to compare. When attempting this, I shorted across the legs of Q310 and popped the fuse. ( boy it didnt take much!) I didn't get the chance to try the trim pot while metering Q308. Hopefully, I didn't cause any damage when this happened. I'll try to acquire a fuse tomorrow, from the shack,and get back to the business at hand.

  I went to increase the idle as suggested. When I turned the dial, there was no change in the value. Its currently set about halfway, as from the factory, and I turned in both directions with no change as the result. Is there something I'm missing?  Should I run the amp to get good and warm before adjusting? I can't help but think there is still a component that is faulty. As I'm posting this, I'm thinking I will meter Q308 again. This time from base to emitter, rather than just collector. To be sure. Could the trimmer be bad,and showing high resistance? That is, if all other values are within reason.

   Finally got some free time to tinker with the hartke. I swapped the transistor at Q308 from the scheme. I must say, I was a little apprehensive about getting  the BEC configuration correct, but after some deliberation I went for it. When the tranny was soldered in,I did the tests that were suggested from previous posts.
No pops or smoke upon power up. I metered  TP 301&302 both to ground and btween. Here's what I found:
          TP301 to G - 65mV
          TP302 to G - 63mV
          Btw TP301and TP302 - 2.3 mV
         Voltage at collector of Q308 -  the DMM flashes 2.3V breifly then holds about
         1.2V
    I haven't fired amp up with instrument or load yet. With the voltages I posted, does it seem as though things are in order? Are there other things I should check before reassembly?   
       

    Finally got replacement transistor for the faulty Q308. I'll get to work asap.
  Happy holidays to you all!

Hey guys. I metered Q308 under the diode setting, and I'm pretty sure its faulty. I couldn't get an OL reading with any combination of the leads. I didn't get an exact replacement of C3200, instead, I got a C2240 transistor. Its supposed to be comparable.
  While I was waiting for my tranny's to arrive. I tried to meter the components Roly had suggested. At least, how I comprehended Roly's suggestions.
  So , my voltage on the collector of Q308, with com. lead on ground and pos. lead on the collector, I read 1.7V.
  When I tried to measure across the emitter resistors, I get 00.0 mV. That was with com. on one leg of the resistor and pos. on the other leg of the same resistor.  However, when I held the com. on earth ground, I was able to read each side of those resistors. I'm unsure if the readings I got are what Roly had in mind,but I tried his equation anyway:
    Sum of voltage across emitter resistors-- 1.6 mV
+ emitter/ base drop of power tran.-- .4mV
+ emitter/base drop of driver tran.-- .3mV
If I'm reading the equation right 2( 1.6+ 400+300)=1403.2mV (~1.4V)
Assuming all readings are correct, does this mean the bias is simply running  cool as was suggested earlier?