For tube rattle I’ve had great luck with the tube dampers from Eurotubes. They’re a bit softer and have a lot more mass than the standard o-ring style type, and seem to be more effective in difficult situations like high-power combos amps.

I love that Dr Z broke the fourth wall and admitted that poor electrical current will make your amp sound like "shit"....LOVE Dr. Z!

This the only Amp builder who's awesome enough to put himself out there to help people, answer questions, and really help people. Thank you Dr.Z Great amps and a great guy.love you!

I have been around vacuum tubes since 1967. I have recovered a few failing amps for myself and others, i have noticed the voltage deviations for myself without anyone to explain to me. But im a trained electronics tech (afl-cio). I recommend that users of vacuum tubes pay Close attention to anything dr. Z had to say. Seriously. This was all true, clearly stated, And in the interest of sharing. Thank you sir. Lbk

I performed this mod on my own JETTA combo. What a difference! Before tube rattle was noticeable on any ringing E note, even with dampers on the tubes alone. Now with the new retainers it is quiet as a church mouse. Only took me about 10 minutes to get this done and less than $10 in parts. Loved the amp before, love it even more now. DR Z's customer support is unmatched in this industry as far as I am concerned.

Thank you for your love of the community, and congratulations on your new source! Mucho appreciado

Good to see you again, Doc! Loving my new Z Master!

👍👍👍👍👍 Thanks Doc! Glad to hear that Dr. Z Amps will be safe from tube shortage!

Dr. z great to have you guys back sharing more good vibes and solid knowledge.

Thank you for this, Dr. Z. It seems to be something I can easily adopt into my amateur amp building. Also, you have a glow about you in this vid, you seem very happy.

Super informative, clearly explained, by a cat who is obviously passionate about his craft. Well done, Doc👏

Dr Z, I really enjoyed the write up about you on the Reverb Platform. That brought a smile inside for sure. It's no wonder that you have such good advice for us regarding our cherished tube amp. Regardless of where they came from. I knew when I saw you and your video the first time, that was going to be important. I would have loved to sit next to you for the Hell Freezes Over Tour to see your friend Joe Walsh jammin' out on your gear. Magnifico indeed. Thanks again for sharing as you do. I understand you

I just learned more in 15 minutes than I’ve ever known about tube amps and I have played tube amps for over 40 years. Thank you Dr. Z! Someday I will own one of your combo’s. 👍

Thanks so much Dr. Z for this video. I was going to buy a Brown Box a few years ago but never did. After watching this video I will now! I miss your weekly videos. Stay well! 😊👏🏻

Amazing for you to share this with us! I have a Dr Z Cure which suffers from tube rattle exactly as the Doc describes, at the tale end of a single on the fretboard. Doesn't even happen if I play the same note on a different string. Having a solution other than an expensive and otherwise unnecessary tube swap is amazing. Thanks Doc!

Thanks Dr. Z for the great information! Always enjoy your AMA's.

Cool video, I'm glad to hear someone else talking about the importance of clean power at the right voltages. I have not only a Brown Box to reduce the voltage for my '67 Deluxe Reverb and my '76 Marshall JMP 2203, but a voltage regulator to stabilize my wall voltage and filter the power as well before it goes to the Brown Box. All this was more to protect the transformers, but the tubes as well.

Thank you man I could listen to you talk valves and amps all day ,...greeti gs from Oz !

First-time listener and now a subscriber I have never owned a tube amp but this explains a lot of what happened to a buddy of mine if I purchase a tube amp, i probably will look at your inventory first

Cool! Glad you’ve found an answer to the this tube shortage situation we find ourselves in. It’s also good to see you sharing knowledge with regards to ways to extend tube life. Nicely done! Tubes are magic… but very few know the correct incantations required for maximum filament specters transfer from the planets of origin. Sigh…

Great to see you posting again.

Absolutely correct on this and also weather impacts the sound of most tube amps. When I first met Kenny Fischer from Train Wreck, he explained to me about weather and magnetic pull. When I got into making my own amps it was 100% aluminum chassis for some of the theories Kenny explained to me early on.

Thank you for your generosity in sharing this expert perspective!

Wow Doc thx so much for the great info!!!! I watch intently your AMA’s!!! Such a great series, you sir are a god send! ❤

You the man, doc! Great to hear from ya again.

Dr. Z, I thank you for sharing your knowledge. I've learned some important things from your videos the last couple years. Knowledge should be shared. It makes us all better. Thank you for making us all better.

I’ve been doing this to any ef86 amp I build that’s higher than 5 watts. Very easy and effective way to cut down on microphonics. Thanx for the tip!

Thanks for sharing that, Dr. Z. That was a very tidy mod with the split compression ring.

Good to see you again Doc

Excellent stuff, sir! I already use a variac, always careful to never crank it. In the studio, it’s practical. A Brown Box is definitely the way to go for any sort of gigging.

Dr Z AMA are always fantastic! Thanks Doc.

You are str8 dope Thanks for sharing There’s no questioning your passion and affinity and knowledge Your clear explanations are much appreciated Thoroughly enjoy listening to you and for what you pass on 🤘

I never knew you could drain your filter caps with just the speaker load! Thanks for the awesome tip.

DR Z! Thank you!!! several looong standing mysteries of my musical life have been explained''''

This is a man who knows what to say and says it.The man is a wealth of knowledge about the dreaded tubes. Thanks for info...always a joy listening to someone who knows what hes talking about.

Thanks for a voice of reason during a time when tubes rival toilet paper! Good stuff!

I’ve been using 50/60 + year old Mullard & Brimar’s in my old Vox, Marshall’s & brown Fender’s. I have a couple of good tube testers( one being a Orange VT-1000’s another is a Vacuum Tube Valley tester) . I have a Brown Box too! It’s an excellent piece of kit!

Looks like a simple and effective fix,thanks...btw,I have a Brown Box and besides protecting the amp's components,all my amps (mostly 60's-70's) sound better at lower voltages...they like it in the 114-117 volt range

Your a really fantastic PERSON. Not thinking about yourself, or money or your business,. You truly care about what is going on in the world and your tips and tricks are helping people like me. I own a studio and several tube amps, Preamps and the like. I have been nervous as of late but you quality fixes has helped me a lot, so thank you. At this time we need to pray for Ukraine and the world, but posts like this go a long way to show your love of music, and I applaud you for it. My next amp purchase is a Dr Z, I put my money where my heart is!!! Or really, where your heart is.

Excellent video. Thanks for the info on the tube rattle . That’s a great upgrade .

I bought a "Tone Preserver" after checking my wall voltage on a Saturday afternoon and seeing 128 volts at the wall. It also had a positive effect on my tone with my tweed based circuits.

Terrific. I've had a Brown Box for a long time at the studio using it with vintage amps but I can see the reasoning to have one for the newer amps too. We get very different voltage from the wall at times. Liked the MacGyver also.

That is a wealth of knowledge given for free! Thanks Doc! ❤

Great video! Very informative and the close ups were on point.

I’ve played through several of your amps over the years. One day, I’m going to own one.

This is awesome when I buy tube amps out will be dr.z's way to just be flat out helpful.

Very much appreciate your presentation, knowledge and sharing. Great job, Fun stuff!

Thanks Z! Also for the brown box info!

What a brilliant video. This guy makes me want to binge watch all his content! Knowledgeable and passionate and has that genuine care for musos and gear. I couldn’t help but think that if Dr Z swore in his videos he’d sound like Lewis Black. 😉

Great thing my father was in Vietnam in the 1960s and I currently have 6 cases of USN 30s to 60s Amp tubes all nos he always said they would be worth money one day

Thanks so much Dr Z!!!

Now you have me looking for a Brown Box for my 1957 Silvertone Model 1392 with 6v6 tubes. Great information insight on Vacuum tubes & Amplifier Voltage sensitivity ❤️

One other thing that a power regulator box of any kind helps with in combination with you running your pedal board off of a battery pack is you get rid of ground loops. Raise your hand if you ever plugged in your amp, your board, and maybe a mic and had hum you had to deal with in some crappy theater or room somewhere. (the entire room raises their hand). DC wall warts plugged into an outlet strip and half-dead batteries are much hair pulled out over the years as well. My friend has a large 12V (recommended since you can easily regulate it down to a clean 9v for many devices) battery pack running his entire setup attached with velcro to the back of his amp. Then also a DC to DC regulator box tied to it (basically a Brown Box but for DC), and the cords all neatly wrapped up. Because pedals also have this same power regulation problem. 9V batteries *quickly* drop to 7-8V. The amp looks a little odd on the back side with several re-usable cable ties, things attached to it, and the two power regulators and power brick, but it's all there. The input to the amp and power to the pedal board are tied together, so just one combined cable from the amp to the board, essentially, thanks to connectors and a little soldering of jacks to make the extension cables work. So all he has to do is roll his amp/speaker combo into the room, plug in the main regulator box to any power cord, pull the pedal board out of his backpack, plug the pedal board into the loop and power it up. Basically 3 30-45 second steps, position the pedal board where it's comfortable, then relax and wait after at most 3-5 minutes of getting things ready. Yes, he's the bass player ;) And he always sounds the same and never has to chance a battery or rely on whatever power is there.

Yes Sir, this video did help. As a matter of fact, it helped a lot. Will most definitely follow your good advice. Thanks Again

Outstanding Idea Dr. Z

Sweet Doc! Thanks for sharing your knowledge! Awesome man!

Helpful as always ...!! Many thanks to you Dr Z ....

Great AMA as usual! I hope this recent “Tubepocalypse” ends soon.

Thank you Dr. Z!

Great video. Thanks for sharing. Tubes and toilet paper. That is what you need in stock in these hard times.😉

Preach, amen, Dr. Z! (Great video!)

Kickass video, Dr. Z. My next amp will be one of yours 😎👍

Great information and well explained. Nice job🙂

I got a NOS 6G6g in a tube lot. It is a lower power Pentode with the same pinout as a 6V6gt. They are rated for a lower voltage and in a 6v6 amp they don't last but 1/2 the time due to the abuse but boy did it sound great. I intend on trying to build an amp with the proper voltage to see what this tube sounds like in a guitar amp circuit designed for this tube. Playing with different NOS tubes is fun, produces unique tones and usually they are cheap. I like octal Preamp tubes, to me they have a really rich sound. I am building a SE amp with 1930's 2 digit tubes which I can't wait to hear. Tube compliment is 77,75, and 42 with an 80 rectifier.

This fix should be a mandatory consideration for amp manufacturers from now on. ; )

Thanks Mike! As always very good advice!

Great video, thanks for sharing your knowledge!

This may be the best video on KZfaq

The Amp Maniac is another good alternative to the brown box. Cheaper too

Great video, Thanks DR Z

This video lesson was awesome!! Thank you 🙏

Dr. Z ROCKS!

Thanks doc! Always fun to watch

Great Video Dr Z You are awesome

You’re the man, Dr Z.

Extremely helpful! Thank you!

Thanks for the words of wisdom!

Thank you for sharing you're knowledge, that very generous. I just heard that Western Electric is planing to make guitar amp tubes. There were a lot of enthusiasm when they put a survey on there website asking people if they would buy tube. BTW not my natural language.

...plus the spring style retainers LOOK so much cooler (!) (I just KNOW me sound will really rock now)

Such an awesome, informative video! Thank you so much!

Thanks Doc for a great lesson.

I built two amps - clones of a Fender 5C1 and a 5C3. I found some rubber washers that fit under the tube sockets. (Actually, over the tube sockets, because the tubes hang down in the combos).

For discharging the filter caps it actually does not matter if the speaker is connected to the chassis, as the output transformer separates the speaker in any case from the DC circuit in which the caps discharge. If not discharging them manually with a high wattage/low Ohm resistor, heated up tubes are necessary for the DC circuit being closed via tube and output transfo.

Blissful generosity of truth Thx. Dr. Z! …i have become familiar with The Brown Box, in fact i’ve reached out to them, super nice team over there in Nashville. How about veriacs, almost same thing, similar, problems for equipment, didn’t/doesn’t Ry Cooder use a veriac?

dr Z is on fire🔥🔥🔥🔥🔥🔥🔥🔥🔥🔥🔥🔥

Thank you very much Z !!

Thanks Doc, very informative.

Love this!

Audiophile here. Thanks for the tips and advice!🤜🤛🍻

Love your channel and content ❤️ Mostly I Love ❤️ your Amplifiers. You the Man

Power scaling is a good way to preserve output tubes and to get overdriven tone at low volumes.

Cool modification, thanks for the video! :-)

Thanks! Great information.

Love your voice! I think you could do some voice overs or cartoons! Love it😂

Wonderful video. You rock.

At home, my wall voltage is 125v. I would probably set the variac at a voltage that would allow the heater filaments to reach spec voltage ie. 6.3 volts, etc. If the heater voltage is lower than spec then the cathode will be starved of electrons quicker leading to shorter life.

Thanks for the tips, doc

I’ve found that modern amp building has pushed output tubes beyond their design spec. Plate voltages are always higher than the tube data sheet recommend. In some cases bias is also set either way too high or way too low. JTM30 I recently fixed had bias set to 130% via the zener diodes that Marshall fitted. I bought a brand new Supro 1623 and it was replating out of the box. Smoking hot. Laney Lionheart LT20 is great. Much lower plate voltages, bias set reasonably low. Getting a respectful 20W out of 4 EL84 tubes. Definitely worth getting some form of power regulation as you’re right, most clubs have horrible power.

Thanks Dr. Z! Just switched V1 and V3 and rattle is gone.

Thanks for sharing this knowledge, cheers!