Tube Amp Sag - Chapter 5: The Transformer Effect

[@biggestgerbil]

Well Chris, I spent a while trying to convince a tube amp disciple friend of mine that "sag" is actually a fault. I have linked him to your Sag series. Thank you.

[@theguitaramptech]

Hahaha 🤣. I love it. For some people Sag is hell. For others it is heaven. I hope I can describe it objectively for your mate.

[@jethrotannis5673]

Thank you so much for this series, as an acoustician and guitar player a lot of the nonlinear effects in amplifiers that contribute to what we consider an amplified guitar tone. Your explanations have been very engaging, informative and most of all understandable so I appreciate you taking this complicated subject and making it something I think I now understand!

[@theguitaramptech]

Thank you Jethro. That is SO NICE of you to say.

[@lestelie4410]

I have really learned a lot from this Sag series. Thanks for creating this.

[@theguitaramptech]

Thanks Les. I am glad you're getting something from the series.

[@uptownphotography]

Very interesting video Chris and super well explained. (as always)... Please however don't have a quiz on Monday!.... Phil NYC Area

[@theguitaramptech]

Thanks mate. Great hearing from you Phil

[@uptownphotography]

@@theguitaramptech Glad to see you're back Chris. I didn't realize...I'll have to play a little catch up! All the best. Phil

[@illi-the-wolf]

Good stuff! Love your patience and thorough coverage! It's a pretty hard topic to make accessible while maintaining a level of explanation necessary for understanding the WHY, and not simply a yes or no. I've always been curious about the particular effects cause power supplies... as you said in the vids, transformers, rectifiers, capacitors... and how they all come together. My old Silvertone is still a mystery to me, but it feels like every link in the whole system is a compromise. HAH! so you put them all together, whack that low E like Pete Townsend, and the whole thing chokes, spits, and sputters for a whole second until it can recover. Other than the annoyance of lacking immediacy (at great volume), it sounds positively diabolical 🤘🏻😈 Really awesome, but highly impractical for most uses 🙄😅 From an ever-learning Journeyman, thanks again for this awesome series! Cheers! ☕ - Brienne

[@theguitaramptech]

Thank you, Brienne. I so appreciate your kind words.

[@alessandromasipersonal]

Hi thanks for these informative and funny videos😂. Could you please make one on the subject of how safe is diming master volume on amps, with reactive loads or attenuators?

[@markusf.3441]

Hi Chris, great video once more and I love your kind of humor!

[@theguitaramptech]

Thank you Markus! What can I say? I'm a fool...and don't mind letting people know. I'm so glad you're enjoying the video series.

[@sarangpadey4144]

Hi Chris. Thanks so much for explaining so many things. Your videos are really highly educational, and interesting.

[@theguitaramptech]

Thank you so much for your kind comments, Sarang. That means a lot to me.

[@bboyzagy]

Great video. It is a joy to listen to you while working. Sometimes I have to pause and rewind. I can't keep up. Looking forward to the next video in the series. 🤘

[@theguitaramptech]

Thanks mate. I have been so busy with repairs that I am yet to record the final chapeter in this series. Hopefully I will catch in the next few weeks.

[@martyncoe3635]

Good stuff keep it up. Looking forward to your next video

[@theguitaramptech]

Thanks Martyn :)

[@midnightraiin4035]

great channel ! you keep it fun : )

[@theguitaramptech]

Thank you Midnight!

[@3MonkeysGarage]

You brought up another interesting thought for me. In possibly answering one question, rises the next. In comparing the Princeton Reverb and the Deluxe Reverb, Obviously the Deluxe comes with more tubes and knobs and an extra transformer I believe. The power transformer is considerably larger to handle this extra load. This makes sense. But we look at the output tubes and find a pair of 6v6 tubes in each. Yet the specs on the output transformer are different. Now, I cant think of the specs positively, but I think the Princeton has 8k impedance, and the Deluxe 6.5k. The Deluxe delivers 20 watts output and the Princeton 12. What puzzles me is there is an equation based on the output tubes handling, and the speaker impedance. Why is the deluxe output transformer ok for the same pair of 6v6 tubes in the deluxe, but not in the Princeton? It also seems I did that math once, and the Princeton value was correct for the 6v6 tubes.

[@theguitaramptech]

That’s a tough question, Alta. There are a couple of angles to approach your question of power output between the Princeton and Deluxe. Firstly they use different Phase Inverters, with Princeton using the lower gain Cathodyne, and the Deluxe’s Long Tail Pair. There’s a also a difference in the rectifier tubes putting out a different B+. And yes, there are variations in OT’s and PTs. The specs on tubes are a guide, and as we know Leo was “flexible” in interpreting DataSheet recommendations. From memory the Datasheets (depending on where you look) are between 8K and 10K for a pair of 6V6s. This will actually vary on the loadline and whether the amp is operating at low levels of Class A or Class AB at higher levels. I am pretty confident that Leo was generous in his interpretation of Specs, but time has proven that his choices resulted in history making amps. A very interesting question and I have added it to my list of future video topics. Thanks Alta

[@3MonkeysGarage]

@@theguitaramptech , excellent. I look forward to seeing you dig into it.

[@moodyga40]

i will be transformed after watching this

[@theguitaramptech]

Hahaha! But hopefully with no more sagging

[@petertimp5416]

👍

[@theguitaramptech]

Thanks Peter. Good to see you back.

[@BradsGuitarGarage]

Sag can happen as we age. But fortunately, there are nasal sprays for that.

[@theguitaramptech]

Hahaha! You’re too young to worry about Sag, Brad ! Um…by the way…did you mention a spray? I’m asking for a friend 😉

[@BradsGuitarGarage]

@@theguitaramptech I just use Deoxit F5, myself. It's about the same bloody price per kg!