A short while ago, I stated that I commited the ultimate sin in tupe amp world and ran one of my cherished Sano 160R's for over a minute without the speaker connected before my stupid brain realized that all the cords were plugged in except the speaker leads.
I finally got the amp out to start troubleshooting the damage. When it happened that day, I just hid the amp in the back room and pouted for the past few weeks about it, not even looking it over.
Well the results are that I'm pretty sure the OT is toast.
There is no audible hum anywhere without the power tubes in which is probably to be expected. And when the power tubes are inserted, the hum gets louder as the volume is turned up. If the volume is turned all the way down, it's quiet. I tried different power tubes too. Same result.
So now I'm looking at OT's I guess.
I want to "upgrade" the OT this time around and this is my first time doing any trannie. So my questions are:
1. What does "upgrading" an OT mean?
2. Does it simply mean a better constructed OT such as Mercury Magnetics versus a Hammond 125 series?
3. Do audio quality OT's make for better guitar OT's? The big 4 tab iron things versus the 2 tab paper wrapped?
4. This amp is a 1967 ish Sano 160R running two EL84 in class A, diode rectified, cathode biased with tube trem and tube reverb. Probably 12-15 watts. 1x12
5. The current OT had a secondary impedance of 8 Ohms
6. I was thinking about something around 8000 primary impedance. Does that sound in the ball park?
7. What exactly is it that I need to beef up if I were looking for maximum headroom? In this case, thats what I want and I want to minimize or eliminate any OT saturation perceived or real.
8. What are the effects if I were to over do it on the primary impedance or under do it on the primary impedance?
9. Anything else you care to add?
Thanks!
Rick
I finally got the amp out to start troubleshooting the damage. When it happened that day, I just hid the amp in the back room and pouted for the past few weeks about it, not even looking it over.
Well the results are that I'm pretty sure the OT is toast.
There is no audible hum anywhere without the power tubes in which is probably to be expected. And when the power tubes are inserted, the hum gets louder as the volume is turned up. If the volume is turned all the way down, it's quiet. I tried different power tubes too. Same result.
So now I'm looking at OT's I guess.
I want to "upgrade" the OT this time around and this is my first time doing any trannie. So my questions are:
1. What does "upgrading" an OT mean?
2. Does it simply mean a better constructed OT such as Mercury Magnetics versus a Hammond 125 series?
3. Do audio quality OT's make for better guitar OT's? The big 4 tab iron things versus the 2 tab paper wrapped?
4. This amp is a 1967 ish Sano 160R running two EL84 in class A, diode rectified, cathode biased with tube trem and tube reverb. Probably 12-15 watts. 1x12
5. The current OT had a secondary impedance of 8 Ohms
6. I was thinking about something around 8000 primary impedance. Does that sound in the ball park?
7. What exactly is it that I need to beef up if I were looking for maximum headroom? In this case, thats what I want and I want to minimize or eliminate any OT saturation perceived or real.
8. What are the effects if I were to over do it on the primary impedance or under do it on the primary impedance?
9. Anything else you care to add?
Thanks!
Rick