Boogiebabies
Well-known member
Original Version without mysterious symbols-
The IIC+ Guide for Dummies
The Chassis Codes –
SR – Sixty Watt -Reverb
SRG- Sixty Watt- Reverb- Graphic
HR – 100 Watt-Reverb
HRG- 100 Watt- Reverb-Graphic
HRGX- 100 Watt-Reverb-Graphic-Export
DR – Simul-Class - Reverb
DRG- Simul-EQ-Reverb
DRGX- Simul-EQ-Reverb-Export
You could get a standard 60 or 100 watt with no graphic or reverb so there are possible S, D and H only chassis codes. Any amp could have an export power transformer, so an X is possible as well. For example, SX, DX and HX.
A 15” could be added to the chassis code designating a long chassis.
The Number after chassis code –
This is the week of production.
Example – A DRG 6 is a Simul-EQ-Reverb from production week six.
For Reference – The DRG 6 was produced in 6/84.
Estimated production is early to mid April 1984.
The Options –
For those original customers who ordered the C+, you can give your self a “Doh” for not ordering a Simul, EQ, EV, Reverb, Export with an Imbuya Head or Combo with a lifetime supply of STR-415’s. Even better, all that and a Series 300 would have been incredible.
For those of you with the foresight, thank you, even if you went with the tolex and the Eminence MS-12. It is a great speaker.
The cabinet and chassis could be ordered as a standard head, standard 1x12 Combo, 1X15 Combo, 15” Head and all could be
tolex, hardwood, but only combos have the SUS-4 Shock Mount option. They could be ordered with the “Boogie” logo or the “Mesa Boogie” logo. The “Mesa Boogie” logo appeared primarily on the long chassis heads, but you could have requested on an any amp.
A ridiculous option known as the 300 series was also available.
The 180 Watt behemoth could be ordered with all the classic options and had a half power switch and most had a limiter circuit to reduce the insane volume of 180 Boogie watts. From time to time, one can see a Simul-Class 300 150W series running two EL-34’s in the center sockets and four 6L6GC’s in the outer four sockets. An Audiologists dream, it was made in a strategic alliance with of one of the USA’s leading hearing aid manufacturers.
The “+”
The plus is dedicated to IIC’s after the 12,500 production.
There have been documented +’s as low as 12400, mainly in some prototype, nearly stock or customized circuits. In recent months I have witnessed two IIC I’s. These are IIC’s that almost made it to a plus, but had “Pull Deep” faceplates and a stock IIC circuit with the RP11A circuit board. These were very interesting times at Mesa. A customer could have chosen a C or a C+, hence, the “I” looks like the initial swipe of a +, but never got the other horizontal swipe so do your loop tests. I could imagine Mesa having to call on all outstanding IIC orders and asking if they wanted the upgrade. In the C+ transistion around 12,3XX/124XX
a “yes” meant a plus and a “no” could be the “I”.
A “+” also refers to any amplifier upgraded below 12,500 that has been verified either by the loop test or visual circuit identification. If your amp was upgraded in the early 90’s to the present, Mesa will have an RA, or Return Authorization verifying the upgrade. Mike B. has a very good catalogue of the amps he upgraded, but please call customer service with the serial number first and let the guy earn a living. The amp may have the 100 or the 105 PT. For those seeking originality, the 105 would be the production transformer. In some opinion’s, and depending on playing style the 100 may be a better fit and offers a smoother tone than the 105. It’s really up to personal preference for tone or originality. Now, if Mesa found two 100’s On a shelf in stock room during the C+ production, they would use them, so never put it past Mesa to be frugal. Some also infer that the Export, or X101 is the most suitable transformer for the C+. Again, it is up to your personal preference. Another view of Mesa’s frugal nature is it took half a year to finally get “Pull Deep” face plates for the 15” models. These 15” chassis +’s have been left to doubt, rumor and speculation as to the amps authenticity. A simple serial number should dispel any questions. If it’s above 12,500, 15” wide and sounds awesome, you should not have to question the “Gain Boost” face plate not being a +.
The Quest –
Sometime in late winter 1983 Randall Smith was attending the Musik Messe in Germany to represent Mesa/Boogie products in the European market. During his absence, Mike Bendinelli and Doug West decided to modify the IIC.
A few weeks of R&D turned out to be a significant step in the evolution of the high gain tube amp. Although the original modifications proved to be a move in the right direction, I am sure that the tone obsessed duo would not be satisfied until they nailed it. The final design did not go into production until about February 1984. In essence, the C+ circuit was born sometime in January of 1984. This circuit has the tendency for extreme gain and brightness. When asking Mike B. why the IIC+ was so bright he kindly replied, “That was Doug West, he kept saying make it brighter”. Doug was obviously looking to shred without the assistance of a boost pedal and got what he wanted. The moral of the story is why the cats away the techs will play. Obviously Randall was impressed with the results and gave the green light for the change in circuit design and production. I also must admit that the 100 PT was probably being phased out. Many 105’s date to late 1983. The X101’s could date back to 1982. Another oddity is that Mesa was going to the “Pull Deep” face plates as well. The 1983 Christmas card shows the IIC with a “Pull Deep” face plate. It makes more sense as it adds a minimum of gain and a wall of bottom end. Knowing Mesa’s frugal nature, they probably sat boxed until they ran out of the previous plates.
The rest is history.
The Tech –
Below the power cord are the famous initials MB, for Mike Bendinelli. No, he did not build every amp, he did the vast majority of final inspections and Burn ins. If you look at the circuit boards they have the initials of the person who populated each individual board. If you’re lucky enough to have a final inspection tag, you we get the initials of everyone who built your amp.
Any C+ could have the initials SDG, BN, CD, RH, LB, PG and RCS, yes the man himself. I noticed my power cap board had these initials. There must have been a pandemic. And lastly, the infamous KDW, later known as Kay Dee. KD, in my opinion was the best wiring technician Mesa had. From the C+ to the early Dual Rectifiers every amp was neat and tight. For those amps not wired with this pride, Mike B. refers to them as having the “IIC Slop”.
To dispel a myth, Mike B. was not the only person to perform the final Inspection of the IIC+ amps. A very small number of them are signed “RCS”. Yes, that it Randall C. Smith. Who do you think covered for Mike when he had to take an off site tech visit to Prince on the Purple Rain Tour in late 1984? Also, Mike had vacations, but he has mentioned coming back to piles of amps so the initials RCS are pretty much an Alien sighting on the back of the IIC+, but they do exist. I have one and have only found two others. Again, either a pandemic or Mike was out in the field.
An 11/84 RCS IIC+ with Simul-EQ and Reverb was sold on E-Bay in April, 2007.
The Face Plates –
The stock face plate should say “Pull Deep” over the Master volume. If it says “Gain Boost” it is the IIC face plate and you should do the loop test regardless of the “+” marked status if the serial number does not fit the sequence. The exceptions would be a 15” chassis above 12,500. Mesa used the remaining 15” IIC face plates before rotating to the “Pull Deep” stock.
Note: Pull Deep Face Plates Appear in the 1983 Christmas Card.
The early “Pull Deep” plates had a dark gray EQ face and the EQ toggle order is –
Top – Auto
Middle – Out
Bottom – In
The Later Plates had light gray EQ face, which scratched much easier. The change in toggle order is probably by customer request or a change in the availability of the switch.
The EQ toggle order is –
Top- Auto
Middle - In
Bottom – Out
The EQ face was later changed back to the darker gray face with the same toggle functions.
The Loop Test –
1) Plug your guitar into the Effects Return jack
2) Switch to lead mode
3) Turn the Lead Drive and Gain controls with a note ringing.
4) If they have NO effect on the volume and sound you have a+.
The Circuit Boards –
Preamp – SP11A – Early 60/100 non Reverb with less ground plane for V3B. The plate voltage was run off the 30uf/500V cap via a wire to the 30uf/500V board cap to the V3B. I’ve only seen one board like it.
SP-11A – 60-100 watt non-reverb
RP-11A Simul-100 and 60 Watt Reverb
The SP-11A and RP-11A were designed for the MK IIC. Their use was continued with the IIC+, Hence, the ability to upgrade from IIC to IC+.
Power Amp – PWR- 7-C1 Simul-Class and 100
PWR -7D – 60 watt.
Filter Cap – PS-1C
The Soup –
The components used in the manufacture of the IIC+ vary widely from start to finish. From resistors to capacitors you will see changes in size, color and type of construction. Some have metal film resistors in certain amps, while others have carbon film. The coupling caps could be Sprague 715P, 225P, Mallory Orange Drops and all could be used in any section of the preamp. The cathode caps are generally black Mallory’s and in certain areas of the circuit, a military specification hermetically sealed silver cap was most often used on the .22 Pull Bright, Graphic EQ, V1A Pull Shift circuit and the 3.3uf cap for the V4B reverb cathode. Substitutions are common so you may see all of the above replaced with the same value in the black Mallory case. The pot tolerances are all over the map. After July or August of 1984 Mesa had to use a 22K series resistor with the Master Volume pot as CTS switched production from the USA to Taiwan. These early Taiwanese pots would have your Master Volume pumping out the volume of 5 at a setting of 2. From this point on, the series resistor stayed and is still in use on the MK IV today. So if you think all IIC+’s will sound the same, think again. Some will rip your head off with the Volume 1 and Lead Drive set to 7 and others may need to go to 8 or 9. The same is accurate for the EQ settings. One of the most consistent components is the graphic EQ. It’s surprising that when you set them all flat, it basically sounds exactly like having the EQ out. A special debt of gratitude goes to Richard Ray who always told us to use our ears and not the numbers on the knobs.
The Schumacher Transformers –
The digits 606 are Schumacher’s EIA manufacturer code.
The digits after are the last number of the production year, example, 3 is 1983. The next two digits are the week of productions, example, 42 is the 42’nd week of 1983. It’s not the Fibonacci Sequence, trust me. EIA 606-342.
60W OT - T60-152019
Simul Output - SC-152019B – Simul-Class
60W PT - 00-162310
60W Export - PT: X62-162318
Simul/60-100 Power - 105-162318 – Power
X101-162318 – Export
Some early IIC+’s may have leftover 100 power transformers. This is just how it was.There is nothing worse than an obsessive IIC+ owner with a slightly different amp from someone else’s. It’s either, “Why Me”, or “Wow, it’s Rare and it sounds better than yours”. Rare is for Filet Mignon and $ 48,000,000 works of art.
The Serial Numbers –
12,500 to 14,400 are pretty much unquestionable. 14,400 to 15,000 in my opinion have early black dot MK III’s in the serial number sequence. There has been visual proof that a 15,000 does exist ( BWK aka Ian Dickey), but IIC +’s between 14,400 and 15,000 just never seem to surface. Anything from 12,400 to 12,499 is a certain possibility, but the loop test is your only way of knowing without pulling the chassis to view the circuit board. Even then, if you do not know what you’re looking at you probably will not be able to tell.
A recent MK III Black Dot surfaced with a serial of 15113 from 5/14/85. It had a DR 13 chassis code which may put the start of the MK III production to 2 or 3 of 1985 which would coincide with the IIC+ production, but it may dispel the 12,500 to 15,000 serial number sequence. With a IIC+ in the 1406X range from 2/85, the C+ may not have even made it to 14,400. If it did, it may have been randomly sequenced in with the early MK III production. An inference to the actual monthly production from 12,500 from April 1984 to 137XX from October 1984 averages 200 units per month for the six month period. From late 137XX in November 1984 to 1406X in February 1985 the average drops to around 121 per month. With the MK III looming Mesa was definitely phasing out the C+ as orders for the III were being generated and amps being built as early as March 1985. Any C+ after March 1985 would have possibly been an attempt to use up the remaining stock and finally push production to the MK III full blast. Even if the IIC+ production was in full effect at an average 121 per month, the sequence would be about 14,370 to 14,400 as an inference. With new MK III orders and fewer MK II orders, the production slowed on average 79 amps less per month, thus reducing the amount of upper range IIC+ serial numbers. The final peek into the model change was the use of the 105-162318 power transformer on the first 150b or so MK III’s. When they were gone, the much smaller unit we know today was assimilated into production.
The End of an Era-
Asking why Mesa quickly went to the MK III is like asking why the earth spins. The circuitry and board design on the MK III was Mesa’s leap from the MK I style circuit boards and labor intensive manufacturing. It would have happened eventually. RCS is an amazing engineer, but an astute business man as well. As the PCB market moved forward with newer, cheaper techniques, so did Mesa. The extra savings may have been necessary to the companies long term survival as the orders increased the labor cost increased while the pricing stayed consistent. Saving an extra
$ 300 per amp in production cost and still producing a bullet proof design was an outstanding achievement and allowed Mesa to move forward with future designs. Obviously, the stripes were a constant evolution to fine tune the III to player’s desires. While the chief designer, play tester and the brilliance from the Chief Technician the core team managed to sell around 13,000 plus units. With the three modes, we had our first glimpse of the future MK IV. It has lasted longer and sold more than any previous MK design. It may get to the point where it will pass them all combined unless the rumored MK V makes its debut soon and the IV is put to pasture.
The IIC+ Guide for Dummies
The Chassis Codes –
SR – Sixty Watt -Reverb
SRG- Sixty Watt- Reverb- Graphic
HR – 100 Watt-Reverb
HRG- 100 Watt- Reverb-Graphic
HRGX- 100 Watt-Reverb-Graphic-Export
DR – Simul-Class - Reverb
DRG- Simul-EQ-Reverb
DRGX- Simul-EQ-Reverb-Export
You could get a standard 60 or 100 watt with no graphic or reverb so there are possible S, D and H only chassis codes. Any amp could have an export power transformer, so an X is possible as well. For example, SX, DX and HX.
A 15” could be added to the chassis code designating a long chassis.
The Number after chassis code –
This is the week of production.
Example – A DRG 6 is a Simul-EQ-Reverb from production week six.
For Reference – The DRG 6 was produced in 6/84.
Estimated production is early to mid April 1984.
The Options –
For those original customers who ordered the C+, you can give your self a “Doh” for not ordering a Simul, EQ, EV, Reverb, Export with an Imbuya Head or Combo with a lifetime supply of STR-415’s. Even better, all that and a Series 300 would have been incredible.
For those of you with the foresight, thank you, even if you went with the tolex and the Eminence MS-12. It is a great speaker.
The cabinet and chassis could be ordered as a standard head, standard 1x12 Combo, 1X15 Combo, 15” Head and all could be
tolex, hardwood, but only combos have the SUS-4 Shock Mount option. They could be ordered with the “Boogie” logo or the “Mesa Boogie” logo. The “Mesa Boogie” logo appeared primarily on the long chassis heads, but you could have requested on an any amp.
A ridiculous option known as the 300 series was also available.
The 180 Watt behemoth could be ordered with all the classic options and had a half power switch and most had a limiter circuit to reduce the insane volume of 180 Boogie watts. From time to time, one can see a Simul-Class 300 150W series running two EL-34’s in the center sockets and four 6L6GC’s in the outer four sockets. An Audiologists dream, it was made in a strategic alliance with of one of the USA’s leading hearing aid manufacturers.
The “+”
The plus is dedicated to IIC’s after the 12,500 production.
There have been documented +’s as low as 12400, mainly in some prototype, nearly stock or customized circuits. In recent months I have witnessed two IIC I’s. These are IIC’s that almost made it to a plus, but had “Pull Deep” faceplates and a stock IIC circuit with the RP11A circuit board. These were very interesting times at Mesa. A customer could have chosen a C or a C+, hence, the “I” looks like the initial swipe of a +, but never got the other horizontal swipe so do your loop tests. I could imagine Mesa having to call on all outstanding IIC orders and asking if they wanted the upgrade. In the C+ transistion around 12,3XX/124XX
a “yes” meant a plus and a “no” could be the “I”.
A “+” also refers to any amplifier upgraded below 12,500 that has been verified either by the loop test or visual circuit identification. If your amp was upgraded in the early 90’s to the present, Mesa will have an RA, or Return Authorization verifying the upgrade. Mike B. has a very good catalogue of the amps he upgraded, but please call customer service with the serial number first and let the guy earn a living. The amp may have the 100 or the 105 PT. For those seeking originality, the 105 would be the production transformer. In some opinion’s, and depending on playing style the 100 may be a better fit and offers a smoother tone than the 105. It’s really up to personal preference for tone or originality. Now, if Mesa found two 100’s On a shelf in stock room during the C+ production, they would use them, so never put it past Mesa to be frugal. Some also infer that the Export, or X101 is the most suitable transformer for the C+. Again, it is up to your personal preference. Another view of Mesa’s frugal nature is it took half a year to finally get “Pull Deep” face plates for the 15” models. These 15” chassis +’s have been left to doubt, rumor and speculation as to the amps authenticity. A simple serial number should dispel any questions. If it’s above 12,500, 15” wide and sounds awesome, you should not have to question the “Gain Boost” face plate not being a +.
The Quest –
Sometime in late winter 1983 Randall Smith was attending the Musik Messe in Germany to represent Mesa/Boogie products in the European market. During his absence, Mike Bendinelli and Doug West decided to modify the IIC.
A few weeks of R&D turned out to be a significant step in the evolution of the high gain tube amp. Although the original modifications proved to be a move in the right direction, I am sure that the tone obsessed duo would not be satisfied until they nailed it. The final design did not go into production until about February 1984. In essence, the C+ circuit was born sometime in January of 1984. This circuit has the tendency for extreme gain and brightness. When asking Mike B. why the IIC+ was so bright he kindly replied, “That was Doug West, he kept saying make it brighter”. Doug was obviously looking to shred without the assistance of a boost pedal and got what he wanted. The moral of the story is why the cats away the techs will play. Obviously Randall was impressed with the results and gave the green light for the change in circuit design and production. I also must admit that the 100 PT was probably being phased out. Many 105’s date to late 1983. The X101’s could date back to 1982. Another oddity is that Mesa was going to the “Pull Deep” face plates as well. The 1983 Christmas card shows the IIC with a “Pull Deep” face plate. It makes more sense as it adds a minimum of gain and a wall of bottom end. Knowing Mesa’s frugal nature, they probably sat boxed until they ran out of the previous plates.
The rest is history.
The Tech –
Below the power cord are the famous initials MB, for Mike Bendinelli. No, he did not build every amp, he did the vast majority of final inspections and Burn ins. If you look at the circuit boards they have the initials of the person who populated each individual board. If you’re lucky enough to have a final inspection tag, you we get the initials of everyone who built your amp.
Any C+ could have the initials SDG, BN, CD, RH, LB, PG and RCS, yes the man himself. I noticed my power cap board had these initials. There must have been a pandemic. And lastly, the infamous KDW, later known as Kay Dee. KD, in my opinion was the best wiring technician Mesa had. From the C+ to the early Dual Rectifiers every amp was neat and tight. For those amps not wired with this pride, Mike B. refers to them as having the “IIC Slop”.
To dispel a myth, Mike B. was not the only person to perform the final Inspection of the IIC+ amps. A very small number of them are signed “RCS”. Yes, that it Randall C. Smith. Who do you think covered for Mike when he had to take an off site tech visit to Prince on the Purple Rain Tour in late 1984? Also, Mike had vacations, but he has mentioned coming back to piles of amps so the initials RCS are pretty much an Alien sighting on the back of the IIC+, but they do exist. I have one and have only found two others. Again, either a pandemic or Mike was out in the field.
An 11/84 RCS IIC+ with Simul-EQ and Reverb was sold on E-Bay in April, 2007.
The Face Plates –
The stock face plate should say “Pull Deep” over the Master volume. If it says “Gain Boost” it is the IIC face plate and you should do the loop test regardless of the “+” marked status if the serial number does not fit the sequence. The exceptions would be a 15” chassis above 12,500. Mesa used the remaining 15” IIC face plates before rotating to the “Pull Deep” stock.
Note: Pull Deep Face Plates Appear in the 1983 Christmas Card.
The early “Pull Deep” plates had a dark gray EQ face and the EQ toggle order is –
Top – Auto
Middle – Out
Bottom – In
The Later Plates had light gray EQ face, which scratched much easier. The change in toggle order is probably by customer request or a change in the availability of the switch.
The EQ toggle order is –
Top- Auto
Middle - In
Bottom – Out
The EQ face was later changed back to the darker gray face with the same toggle functions.
The Loop Test –
1) Plug your guitar into the Effects Return jack
2) Switch to lead mode
3) Turn the Lead Drive and Gain controls with a note ringing.
4) If they have NO effect on the volume and sound you have a+.
The Circuit Boards –
Preamp – SP11A – Early 60/100 non Reverb with less ground plane for V3B. The plate voltage was run off the 30uf/500V cap via a wire to the 30uf/500V board cap to the V3B. I’ve only seen one board like it.
SP-11A – 60-100 watt non-reverb
RP-11A Simul-100 and 60 Watt Reverb
The SP-11A and RP-11A were designed for the MK IIC. Their use was continued with the IIC+, Hence, the ability to upgrade from IIC to IC+.
Power Amp – PWR- 7-C1 Simul-Class and 100
PWR -7D – 60 watt.
Filter Cap – PS-1C
The Soup –
The components used in the manufacture of the IIC+ vary widely from start to finish. From resistors to capacitors you will see changes in size, color and type of construction. Some have metal film resistors in certain amps, while others have carbon film. The coupling caps could be Sprague 715P, 225P, Mallory Orange Drops and all could be used in any section of the preamp. The cathode caps are generally black Mallory’s and in certain areas of the circuit, a military specification hermetically sealed silver cap was most often used on the .22 Pull Bright, Graphic EQ, V1A Pull Shift circuit and the 3.3uf cap for the V4B reverb cathode. Substitutions are common so you may see all of the above replaced with the same value in the black Mallory case. The pot tolerances are all over the map. After July or August of 1984 Mesa had to use a 22K series resistor with the Master Volume pot as CTS switched production from the USA to Taiwan. These early Taiwanese pots would have your Master Volume pumping out the volume of 5 at a setting of 2. From this point on, the series resistor stayed and is still in use on the MK IV today. So if you think all IIC+’s will sound the same, think again. Some will rip your head off with the Volume 1 and Lead Drive set to 7 and others may need to go to 8 or 9. The same is accurate for the EQ settings. One of the most consistent components is the graphic EQ. It’s surprising that when you set them all flat, it basically sounds exactly like having the EQ out. A special debt of gratitude goes to Richard Ray who always told us to use our ears and not the numbers on the knobs.
The Schumacher Transformers –
The digits 606 are Schumacher’s EIA manufacturer code.
The digits after are the last number of the production year, example, 3 is 1983. The next two digits are the week of productions, example, 42 is the 42’nd week of 1983. It’s not the Fibonacci Sequence, trust me. EIA 606-342.
60W OT - T60-152019
Simul Output - SC-152019B – Simul-Class
60W PT - 00-162310
60W Export - PT: X62-162318
Simul/60-100 Power - 105-162318 – Power
X101-162318 – Export
Some early IIC+’s may have leftover 100 power transformers. This is just how it was.There is nothing worse than an obsessive IIC+ owner with a slightly different amp from someone else’s. It’s either, “Why Me”, or “Wow, it’s Rare and it sounds better than yours”. Rare is for Filet Mignon and $ 48,000,000 works of art.
The Serial Numbers –
12,500 to 14,400 are pretty much unquestionable. 14,400 to 15,000 in my opinion have early black dot MK III’s in the serial number sequence. There has been visual proof that a 15,000 does exist ( BWK aka Ian Dickey), but IIC +’s between 14,400 and 15,000 just never seem to surface. Anything from 12,400 to 12,499 is a certain possibility, but the loop test is your only way of knowing without pulling the chassis to view the circuit board. Even then, if you do not know what you’re looking at you probably will not be able to tell.
A recent MK III Black Dot surfaced with a serial of 15113 from 5/14/85. It had a DR 13 chassis code which may put the start of the MK III production to 2 or 3 of 1985 which would coincide with the IIC+ production, but it may dispel the 12,500 to 15,000 serial number sequence. With a IIC+ in the 1406X range from 2/85, the C+ may not have even made it to 14,400. If it did, it may have been randomly sequenced in with the early MK III production. An inference to the actual monthly production from 12,500 from April 1984 to 137XX from October 1984 averages 200 units per month for the six month period. From late 137XX in November 1984 to 1406X in February 1985 the average drops to around 121 per month. With the MK III looming Mesa was definitely phasing out the C+ as orders for the III were being generated and amps being built as early as March 1985. Any C+ after March 1985 would have possibly been an attempt to use up the remaining stock and finally push production to the MK III full blast. Even if the IIC+ production was in full effect at an average 121 per month, the sequence would be about 14,370 to 14,400 as an inference. With new MK III orders and fewer MK II orders, the production slowed on average 79 amps less per month, thus reducing the amount of upper range IIC+ serial numbers. The final peek into the model change was the use of the 105-162318 power transformer on the first 150b or so MK III’s. When they were gone, the much smaller unit we know today was assimilated into production.
The End of an Era-
Asking why Mesa quickly went to the MK III is like asking why the earth spins. The circuitry and board design on the MK III was Mesa’s leap from the MK I style circuit boards and labor intensive manufacturing. It would have happened eventually. RCS is an amazing engineer, but an astute business man as well. As the PCB market moved forward with newer, cheaper techniques, so did Mesa. The extra savings may have been necessary to the companies long term survival as the orders increased the labor cost increased while the pricing stayed consistent. Saving an extra
$ 300 per amp in production cost and still producing a bullet proof design was an outstanding achievement and allowed Mesa to move forward with future designs. Obviously, the stripes were a constant evolution to fine tune the III to player’s desires. While the chief designer, play tester and the brilliance from the Chief Technician the core team managed to sell around 13,000 plus units. With the three modes, we had our first glimpse of the future MK IV. It has lasted longer and sold more than any previous MK design. It may get to the point where it will pass them all combined unless the rumored MK V makes its debut soon and the IV is put to pasture.
