Ref 750 SE story

[DrRob]

Three or Four weeks ago I witnessed the second catastrophic failure of a tube in one of my Ref 750 monoblocs. A prompt exchange for a pair of 450s and my crippled amps were off to ARC.
Several days later I was told that the most current event involved a power regulator and resulted in damage to other components. I was then asked if I wanted to proceed with the SE upgrade that included circuit mods as well as the KT150 tubes.
I of course agreed and last friday my upgraded Ref 750 SE amps were delivered and installed.
Physical changes include an SE logo affixed to the top panel behind the last row of tubes and of course the KT 150 tubes.
First impressions reveal a level of musicallity not present previously. I will be looking forward to experiencing the evolution of the sound of these really special amps.

[2fastdriving]

Originally Posted by DrRob

Three or Four weeks ago I witnessed the second catastrophic failure of a tube in one of my Ref 750 monoblocs. A prompt exchange for a pair of 450s and my cripled amps were off to ARC.
Several days later I was told that the most current event involved a power regulator and resulted in damage to other components. I was then asked if I wanted to proceed with the SE upgrade that included circuit mods as well as the KT150 tubes.
I of course agreed and last friday my upgraded Ref 750 SE amps were delivered and installed.
Physical changes include an SE logo affixed to the top panel behind the last row of tubes and of course the KT 150 tubes.
First impressions reveal a level of musicallity not present previously. I will be looking forward to experiencing the evolution of the sound of these really special amps.

Sounds awesome, looking forward to your impressions! And welcome to AA!

[Frank750]

Originally Posted by DrRob

Three or Four weeks ago I witnessed the second catastrophic failure of a tube in one of my Ref 750 monoblocs. A prompt exchange for a pair of 450s and my cripled amps were off to ARC. Several days later I was told that the most current event involved a power regulator and resulted in damage to other components. I was then asked if I wanted to proceed with the SE upgrade that included circuit mods as well as the KT150 tubes. I of course agreed and last friday my upgraded Ref 750 SE amps were delivered and installed. Physical changes include an SE logo affixed to the top panel behind the last row of tubes and of course the KT 150 tubes. First impressions reveal a level of musicallity not present previously. I will be looking forward to experiencing the evolution of the sound of these really special amps.

How long have you had the Ref750s DrRob? I had the Ref600 and Ref610 but suffered through so many failures resulting in the return of the amps to Minnesota that I finally gave up and switched to SS. I still think about the 750s but don't feel like dealing with the problems again.

[DrRob]

I've have had the 750's since April '14. They had 1800 + hours before the upgrade. With the exception of the tube failures I noted the 750's have been very reliable.

[triode12]

According to my tech (who was formerly the authorized ARC tech for my country), the failures of the Ref 600s (mk1-3) were all due to the mounting of the circuit boards vertically. Moisture and dust would collect on the boards and the thick PCB tracks would arc across each other. He has attended to many issues with the Ref 600s - even the Mk3 was not immune to the same problem.

I am surprised, that the 750s are still having issues.

[kngale1]

Originally Posted by DrRob

Three or Four weeks ago I witnessed the second catastrophic failure of a tube in one of my Ref 750 monoblocs. A prompt exchange for a pair of 450s and my crippled amps were off to ARC.
Several days later I was told that the most current event involved a power regulator and resulted in damage to other components. I was then asked if I wanted to proceed with the SE upgrade that included circuit mods as well as the KT150 tubes.
I of course agreed and last friday my upgraded Ref 750 SE amps were delivered and installed.
Physical changes include an SE logo affixed to the top panel behind the last row of tubes and of course the KT 150 tubes.
First impressions reveal a level of musicallity not present previously. I will be looking forward to experiencing the evolution of the sound of these really special amps.

DrRob, how much was the upgrade?