How To Bias a Deville Amplifier

[@gvb54]

Been using tube amps for 25 yrs and never truly understood how they work just loved the sound. Your series on tubes is second to none! Thank you so much for posting this and sharing your knowledge, it is appreciated. Looking forward to more.

[@antwannn111]

Best explanation ever... Happened to be the first video I clicked on, what luck. You have just saved me hours of my life! Thanks for that!

[@ArtDonna84]

Rob, was looking for a simple video for biasing a Vibrolux and came upon this one. Since I purchase tubes like I'm sure many below from you all, I was happy to find this video. Very well presented, clear to understand and a great help for dummies like myself. Thank you.

[@rudolphgaroa1960]

G'day Rob, I hope you've been well in this time of crisis. I'm 11 years or more late on this, but I guess it's better late than never. Amongst most of the Biasing for the Hot Rod Deluxe I've seen, I decided to follow yours because it is the most clear (visually plus the audio & explanations) I've just done my Hot Rod today .. with 101% confidence thanks to you. Just one thing which I thought is super important, for those non-techo's like me. .... that's the detailed settings of the multimeter. I had to go over your video a few times to be sure. Where you set the multimeter to "Volts" to take the reading of the plate behind the Bias adjust knob, but mentioned very little about changing the multimeter to mV when setting the actual Bias while at the same time looking at the mV readings. I was lucky I saw the different settings showing on the video for your multimeter and so followed. In my case every detail of the procedure is important. Hope this will help you help us (non-techos) for future video releases. Stay well and all the best. ru

[@VintageRandom]

Excellent instruction. Just got a HRDV 410 and walked through the steps. Fantastic result. Beautiful cleans for days and very silent even with single coils. Thanks very much.

[@bazjones7349]

I have a mk2 deville ( made in mexico) I fitted a fromel supreme kit ,and changed all the valve sockets to gold ceramic .I usually set the bias a 68 mv ,I also recently changed the first ax12 to a at12 ,this has made the volume much more controllable

[@TitlefightPA]

This video was so helpful. Replaced the tubes in my Fender Blues Deluxe reissue. Worked great! Thank you!

[@bobandy3197]

Same test point on the blues deluxe? Service manual for deluxe is different.

[@yusufandongvlogs6954]

MAds

[@GameLevelEditor]

Most excellent straight forward biasing video ever.

[@mjs28c]

Great video! Very helpful and informative. I've had my Deville for probably 10 years and I was never 100% happy with the gain/overdrive channel. It sounded.......raspy.....not smooth at all. I installed a Fromel kit, which made things better....but still....something wasn't quite right. I had the amp serviced/biased/etc. Again.....better, but not quite 'there'. So I found your video and did as you suggested. The bias was set at 58-59, and the blue trimmer was epoxied in place. I powered-off and carefully trimmed the epoxy. I set the bias to 68 (the alleged 'sweet spot'), let it warm-up and took it for a spin. Much better! I was more satisfied with the gain....definitely an improvement. I also thought the clean channel had improved as well.....I could hear a difference. I kicked the bias up to 70 and I'm happy with it. Looking forward to next band rehearsal.

[@wildparlor5456]

Great info and sick blues at the end. Love it

[@01MrGibson]

Good. Point taken. I just bought a fender hotrod deville that had a very loud microphonic howl, seemed to be the first valve in line of the 3 small ones, was going to buy a complete new set, but then I just swapped the first to around absolutely perfect now. A good hint to try first.

[@dstrats]

Great video, well done! I own a HotRodDeluxe and this thing is always frying tubes. I took it to a tech who claimed to have biased it correctly but two days later at a gig I only had one 6L6 working, glowing extremely bright amber, distorted badly on the clean channel (I only use the clean channel) until it died all together. This was back in '05. I have a tech friend install new tubes 'bout a year ago and bias it, and it distorted again. I bought new tubes and I'll use your vid to DIY. Thx

[@01MrGibson]

Hi. OK understood now, I'd got milliamps on my mind. Got the right measurement now. Thank you for all your help. Brilliant.

[@jeremyberg9693]

wonderful presentation!!! breath of fresh air!!!!!!

[@real_fjcalabrese]

Great video! Kudos for mentioning the connections.

[@moogmanXanders]

got the new JJs in the mail today and checked em out by swapping one position at a time, swapped V3 nothing put the original in. tried V2 still nothing, tried V1 which I suspected and got a low volume fuzzy tone even on 12, so I put another one of the JJs in the V2 position and she jumped back to life with even more tone, put the last new one in just to complete the set and i figure ill hang on to the one good one for emergencies till i get a few spares, Thanks again for your help

[@LeviSiccard]

hey, yes, all the solder connections are fine. I just thought it was strange that i couldn't get it under 73mV but i made a call to the store and they said it's perfectly normal. They offered me to return them in if i wanted, so they could give me another pairbut as you said 73mV is a nice value. Great vid by the way! nicely explained for electronica noobs (like me)

[@yimmiytube]

I don't know much about amps,I'd rather watch your playing.I like it,U teach?

[@memoglz]

@TubeDepotTV i knew it was a legacy because of the bridge and the tremolo arm.... they´re just the best guitars for me, i have the legacy special model, and also have a deville amp... awesome combination... excelent tutorial i am about to do this to my amp, greets!

[@j_music_8779]

Nice video man! Very informational and easy-to-follow 👍

[@JeffDumps]

Excellent video production and clear instruction, thank you!

[@jamessanscrainte9533]

Thanks so much for making this video. Great explanation and instructions.

[@moogmanXanders]

thanks, I also tapped the reverb tank and could hear the springs through the speakers so thats working ok, it was bad timing too cause my Wampler tweed 57 pedal had just came in the mail and I was itching to try er out. Still in Awe over how many tools and tube accessories you have on the tubedepot store, wouldnt mind getting one of the 18 Watt british amp Kit sometime in the future.

[@PeterDad60]

That's some purty good playin at the end Rob!

[@bill.clifford.59]

Thanks for this awesome video! I just bought a deville and this video is a big help!

[@4Dcruz]

@TubeDepotTV thanks a lot! I ended up settling at 70mV, messed with it back and for for a while and 70 just seemed to be a good middle ground where i got the best tone without killing my tubes

[@cassvirgillo3395]

Hi Rob, Tube Depot, Just a little FYI, the ribbon connectors on the Deville can come loose and this will cause issues with the amp and performance of. El Paso Tube amps on KZbin did a video about this problem, worth a view. Discharge filter caps first when working on amps, use only one hand when hooking up meter. Also see Uncle Doug on YT, very knowledgeable. Take care, C.

[@tommyapplegate30]

Thank you I found the problem it needs new tubes 1 overloaded due to the lack of electricity. I'll retube it & be careful of what is tied into the outlet before I plug it in. Thank you for your videos on tube amps & a walk though of my & many other peoples post.

[@glennkubik3774]

Very Good Explanation! Glad you mentioned safety. Too bad for the Test Point - the PCB should have a Tip Probe socket for holding the DMM's probe. To minimize the chance of getting an electrical shock (although not UL approved/tested) I wear the Black thicker Mechanics "Nitrile Gloves". Love 6L6 amps like the Deville (I have a Peavey ValveKing 2x 6L6). A dab of Nail Polish or RTV/Silicone keeps the pot from moving after being set.

[@devinyuceil]

Thanks dude, great video, very well spoken and nicely put together! I'm just about to change the tubes on my Blues Deville and I hope I goes as smoothly as your video!

[@zoomer51]

when you said "there's a newer model", i suppose you were talking about the hotrod deville 3 ? as far as gettin new tubes, i'm gonna check out your catalogue see if there's any special custom sets for the 212 deville.. Thx once again for you answers and kindness.

[@rockventures]

Brilliant vid and pickin ! The lad just picked up a HR Deluxe ii ....fantastic sound except the power tubes are noisy on some low notes. Gonna try some damper rings but if that doesn't work then may be putting your instructions to use soon with a pair of new tubes.

[@andrewt248]

I have a Jet City JCA20H 20w 2xEL84 head. It doesn't have the nifty test point on the pcb. I saw a video here that showed how to bias it with a multimeter and I'd just like to verify the procedure before I make any adjustments. They suggest to check the plate voltage which is supposed to be around 350VDC (mine was 370VDC), then check the milliAmperes at each tube and plug those numbers into the following equation: 11.5watts x (600 / [PlateVDC]) = X [milliAmperes].

[@MiloMeskensOfficial]

If I have 4 6L6 (100w) will I still have to bias it to 60 mV?

[@bostonmassappeal]

Awesome. One of the best vids on youtube.

[@guitartec]

Yeah, that makes some sense. After I watched your vid, I perused other utube biasing vids, and all the techs were touching the tubes and viewers were commenting the same thing I said to you (I guess I'm not as alone as I thought in my old thinking). It would be so cool if you could demystify this old wives tale by doing an unbiased test (no pun intended) using two sets of matched power tubes, one totally filthy, and one spotless.

[@rccarsandmusic2641]

thanks for the help I lowered my bias as low as it can go 30. now its playable beyond 1

[@nickgiovannucci7922]

Oh ok! Thank you for the quick reply! Your video was very informative and helpful!

[@MrAnders1976]

I think it depends on power transformer current capacity. With most amps I agree with you but take a fender princeton reverb amp with 2x6v6 and 4x12ax7 tubes feed from a 325VAC/70mA transformer with just 2A of filament current. It is taxed really hard, and will B+ will drop when biased hot. The 60mA for both tubes suggested by fender is with screen current also. Eurotubes has a video that shows that a test point reading of 91mV = 78mA plate current, which gives ~12- 13 mA screen.

[@rafaelzengo5534]

Great video. Cool guitar playing too. I thought these amps had 2 speakers.

[@bahady30]

Hello Rob. I'm an owner of the Hot Rod Deluxe ( 12 inch speaker ) and the amp is the smaller brother of the Deville but looks prett much the same inside. I'm living in Holland so our current is 230V AC unlike the 110V in the states. Does that make any difference in biasing the power tubes? I read somewhere that you recommend 70mv for a Hot Rod Deluxe. Is this a safe value for my amp. I appreciate it that you took the time to explain this ! Thanks

[@mrgroise]

Excellent. Thank you for your time and incredibly helpful reply. I really appreciate it.

[@robrobinette]

Very nice video and it's just not right that your top technician can play the guitar like that. Very impressive.

[@TubeDepotTV]

I so wanted to be a guitar god ... but sadly my playing has always been well below the "god" rating. Therefore, I had to find a real job ... enter electronics tech.

[@MiloMeskensOfficial]

and wich multimeter did you use?

[@Sandelb]

Awesome video, just what I was looking for. Recently picked up one of these babies used. It played fine for a day or so then started doing some heavy volume fluctuating. The jewel light also fluctuated but not always in synch with the volume trouble. I popped the back off and checked the connections as Rob did in the video and they looked solid. It's my first tube amp and don't want to assume anything. Would a good first step be to pick up some new power tubes and pop them in?

[@MatthiasLenardt]

Really good. Keep on rockin.....

[@WillCorg]

I bought my DeVille 2/12 in 1996 and I've never adjusted the bias level... the original Fender tubes burnt out in 1998 and I replaced them with a set of tubes from a guy I found in the Nickel Ads in Portland Or. They've never gone bad and still work to this day! I'd be interested to see what the bias level is set to?

[@aidodonnakgb3065]

this was very informative, cleared up a few things for me. cheers mate much appreciated p.s guitar playing at the end was killer, should upload a video with just you jammin

[@rubentrevino6288]

excellent video and kudos for providing safety review . . . very important!

[@TubeDepotTV]

thank you for your wonderful comment.

[@OhHeyFixItGuy]

Hey Rob I really appreciated the video as I just bought a Blues Deluxe and it looks like the tubes are in same configuration. I have a lot of noise coming from the middle 12AX7, do I need to bias them as well as the 5U's if so is there are similar reference point and and adjustable potentiometer for the other side? Really appreciate the video, going to save me some money. Oh yah the noise goes away when I put pressure on the tube so maybe a quick solder is all that's needed.

[@Chromatype]

I played a gig last night with some band and the other guitar player's amp died on the gig...it was a Hughes and Kettner though....he came back 20 minutes later from his house with a Deville!

[@tamuna61]

Great vid, clear and to the point. thanks for that

[@sixstringer82]

Hi Fantastic video I plan to change my tubes watching this video as I have a hot rod deville. Last time I played the sound was getting fuzzy and losing power. Do you suggest any different tubes to the ones originally in the deville? another question. How do I know if the pre amp tubes need changing also? Im I correct in saying you changed the power tubes only in this video? is it the same method for pre amp tubes? Thanks. sorry for long message Cheers

[@al94551]

Hi Rob, Like the video. Good solid and easy to follow. I have just changed to TAD 6L6 tubes and during biasing could not get less than 61mV at the bias test point (highest voltage pot would go was -60V, which gave me 61mV at the bias test point). I therefore backed off the pot voltage until I got 70mV as the bias voltage. Is there large tolerances between amps, or should they all be able to get 60mV without having the pot at max counterclockwise Regards, Allan

[@ChadBoston]

Fantastic presentation!

[@TubeDepotTV]

Thanks ...

[@someguyonaguitar]

@TubeDepotTV Thanks man. I just got JJ 6l6gc's and a tung sol 12ax7 for the V1 spot and two electro harmonix for the V2 and V3 preamps. Sounds great even without biasing it yet. Which leads me to my next question: I have an analog multimeter, any idea what setting it should be on? AC or DC? 500, 250, 50V?

[@erikolson2897]

Hey there thank you for your speedy response. so I seem to have found out the source of the issue, and I'd thought I'd share what I found. The speaker jack was plugged into the ext. speaker output on the chassis. someone must have plugged it back in incorrectly. does that sound like that would cause that kind of volume drop?

[@brokenbones112]

Hi I opened my hotrod deluxe up and its got a pair of sovotek 5881's in the power section, now it is 10 years old and i am not the origional owner, so keeping this in mind and the fact that i have no idea what im doing other than dont touch anything on the circuit board is there a different bias point for these tubes

[@harrykarmona]

Hi! great tutorial! I have a question, I have a old hot rod deluxe made in USA and I would like to know what are the valves you recomend me. I would like to change all of them. Thanks from Spain!

[@funkyjones]

Wow! You made it look easy. I have a question. I have a Hot Rod Deluxe. I put new JJ power tubes in and the started rattling shortly after. The guy at JJ said it's because I have a combo and the amp vibration is the cause. What do you think? Also what replacement tubes do you recommend? I play rock, blues, country.

[@01MrGibson]

I've just checked the bias its 20mA theres a red marker thats never been moved but I'll buy a new meter to be sure the reading is correct. Thanks.

[@jordanlcombs]

When biasing my hot rod deville, my voltage meter won't pick up any readings off of my bias test point. But it had a reading when turning the voltage up when the amp was on standby.

[@01MrGibson]

Hi. Why is the power tube guard missing. Good info by the way.

[@MrAnders1976]

great video.. WIth 485V plate (schematic) a value of 74mV (2 x 37mA) is a good medium warm bias (60% of max dissipation). The hot rod deluxe shows 431V plate and Fender recommends 60mA (30mA pr tube). That is cold for a set of large 6l6GC (30watt) tubes (less than 50%), at those voltages. With that amp you could go up to 84mV (2 x 42mA) for 60% dissipation. Even 90mV (2 x 45 mA) is not that bad. Just watch the plate voltage, my guess is that with the small PT it will drop when biasing hot.

[@Cro55co]

Thank you so much for your video mate! Can you please tell me why did you need to read negative voltage before you read positive also do you only bias when changing power amp tubes or also when changing preamp tubes! Many thanx

[@J.C...]

Yep. These have a test point and a potentiometer to adjust it. 👍

[@justplanecrazy3d]

Good video, nice guitar playing ! I just replaced all the tubes on my brothers Deville, looking at the back of the amp, the left power tube looks like it never comes on, the amp still plays and seems strong. Could this be the solder connection you were talking about, or else what may be causing this ? Thanks !

[@sixstringer82]

Thanks for the reply and help David or guys at tube depot!!

[@guitartec]

Great vid. but I gotta question.... I have been told by techs to never handle vac tubes because the dirt & oil from your fingers makes the tube run hotter and have a shorter life span. Iso alcohol is to be used to clean tubes if they are touched. Has this rule changed because of some techno improvement I don't know about?

[@justplanecrazy3d]

Thanks for the reply TubeDepotTV.

[@Satchmoeddie]

I just had a Blues DeVille come in with major blow out damage on the board, 5 resistors, a couple of caps, and a chunk blown out of the board. The ONLY remedy is to cut out the bad part of the board and jumper everything. There is so much carbon tracking to ground the only other option is a new board, or new amp. If only you knew how little it costs to make on of these!LOL They still sound good. They are just hard to repair when things go wrong, and hard to modify without making a mess.

[@Barnekkid]

Very good video. How do you bias an amp that doesn't have the test point, say like a 64 blackface with an AB763 circuit?

[@deepbooka]

Hi Rob! I follow your tips in my deville 2x12 and all ok.Now I wanna try with a pair of TAD Tubes 6V6GT-STR. Can you tell me the save level on test point for these tubes? Maybe a good video like this....This would be good!!...(Very people interested). Thank you!!

[@van637]

good video!!!!! how often i have to change my tubes if i only play a couple hrs a day??

[@4Dcruz]

i have a Hot Rod Deluxe. I picked it up used, and swapped out all the tubes today. 2 brand new mesa boogie 6l6 for power, and 2 groove tube 12ax7-r for the pre. Since it's used, and i don't have the manual, any advice about what to bias to? Close to 60 like the deville? Already gave the new tubes a quick test, sounds much better.

[@DjNorbax]

Nice vid, never had seen all this biasing thing ......Btw, I also have a Fender Deville with Sovtek tubes but one of the preamp's is microphonic so I'm thinking of buying new ones. Which preamp tubes would you recommend for this amp? Thanks

[@almpinho]

Hi, fantastic video! I have this same amp and at now I know do the bias adjustment in my HRD 2x12". But I would like to know which is the plate voltage of this HRD for calculate the 100% of bias value and 70% also. I thing this value varies from each same amp and I would like to know how measure this value. Please, if it's possible to you, make a video explaining how to measure the HRD 2x12" plate voltage value!!! Thanks

[@bromporke]

I followed all the directions with my Deville 2x12 and the DC mV reading was all the way up at 180mV at the testing point. I couldn't turn down the pot enough to get it down to 60mV... my bandmate tested his 4x10 Deville and got a normal reading.... what's wrong with mine that it would be running that hot?

[@deepbooka]

@TubeDepotTV Ok Rob but tell me somenthing The TAD web says: 'The bottle is made from very thick glass and my sample of four were consistently straight and internally well aligned. I have no worries at running them at 450 volts and above average current. The plate construction is more conventional than a JJ but TAD has added cooling fins to both halves of the plate structure. This helps get rid of the excess heat when you run them outside of the standard 6V6 envelope.'

[@mrgroise]

Is there any chance of salvaging a pulled PCB trace leading to the power tube socket? I'm fairly confident with soldering, and I have 18 gauge solid core wire I've used to replace bad traces in guitar pedals. I think my concern is long-term sustainability. It seems like once the solder mask is pulled, the copper trace continues to deteriorate pull off the board. I assume the only alternative would be a lot of work around hand wiring the traces off those finicky ribbon connectors.

[@putimail]

Hello! I am new with tube amps and I am planning to buy one. The amp I am planning to buy also has 2 power tubes. Is this method you showed is alwasy the same? 1. Turn the tripmot full counterclockwise while in standby mode 2. Turn the amp on (switch it out of bypass) and set the voltage to the desired amount while touching the sowder spot of the powertube? What do you recommend when replacing with different tubes? Does the safe voltage remain the same? Thank for you reply in advence!

[@stephentrageser]

I've got a Blues Deville, the reissue and I think the newer version of that, so the inside looks pretty much the same as the Deville here. I can see the bias pot and test point in the same position. The only thing I can't figure out for sure is whether or not it has the same recommend bias of 60mV. Is it? Where do they hide this information in the specs, or can you derive it from something else?

[@jacobchidester1079]

Great video. I tried biasong my own amp, but after I stop turning the bias pot the voltage just keeps climbing and climbing.The amp will sit steady up to about 55mV but even the tiniest turn past that and it slowly climbs up and up into the 80s and 90s. Any thoughts on why that might be?

[@PeterDad60]

I used this most excellent of all tutorial's in 2015 for biasing my new Fender Dot Rod Deville III 410. I deliberately set the Ma to only 57-59 Ma to prolong tube life. Now I have been wondering to my self if this is too cold and did I sacrifice tone. I can not get power tube break up at any volume and when it's at full volume I get that "ice pick" pain in my ears it's so loud. I think I shall re-bias to the 60 Ma and maybe change V1 to the 12AT7 which has 60% as much gain as the 12AX7 which has 100%. The available Pre Amp tubes have these gain factors: 12AX7 100% 5751 70% 12AXT7 60% 12AY7 45% 12AV7 41% 12AU7 19% Changing tubes is not difficult so I may even set the bias as high as 70 Ma or 80 Ma just as rob mentioned. If the amp then sounds warmer to my ears it will be worth the cost of purchasing new tubes sooner. After all I did not purchase the amp to save money but rather to enjoy the tone of a fine amplifier. He, he, as usual I outsmarted myself with the too cold re-bias from the factory settings of 60 Ma. Live and Learn! Thanks again Rob for your video, for re-biasing/bias of a Fender Deville it's the best one on You-Tube!

[@PeterDad60]

I tried 2 different 12AT7's and at volume over 4 1/2 the amp made a strange noise. I have decided my amp only want's 12AX7's.

[@BETILYO]

Hi! first of all thank you for this video it´s very helpfull! i have a blues deluxe amp, i just install mi power tubes they are matched power tubes and rated 10 so i did the bias as you teach here, and once i test the amp i notice that the amp was breaking up really easy, i understand if the gt are matched 10 the amp shouldn´t break up that easier, did i do something wrong? maybe because i leave it on 60MV? (sorry for my english i´m from El Salvador) thank´s again mi friend!

[@entrenuves]

Holy shit thank God for this video!!! So well explained!!🙌🏻🙌🏻🙌🏻

[@troydog86]

i got a hold of some tad 6l6gc-str, they sound fantastic! biased at 75mv excellent tone.

[@hhscadets0925]

At 1:23 you say to not touch anything without first discharging the amp. How is this done? Will simply turning it off and unplugging your amp discharge it after a period of time?

[@xenod1066]

Mike Lowrey Well, probably, after a month.. I'm tempted to say "if you have to ask, don't do it." - Not to be snarky, but because it's actually dangerous. A power resistor is used to discharge the power supply filter caps. There's a lot of videos about it. If in doubt, take it to your tech.

[@bart99gt]

I made a wand out of a cheap screwdriver, alligator clip and a 1k resistor. Alligator clip lead is soldered to the resistor, resistor to the Clip the alligator clip to the chassis, touch the end of the screwdriver to the positive end of one of the filter caps. That will usually discharge most caps in less than 10 seconds. They will discharge after turning the amp off while the cathodes are still hot enough to emit electrons. But don’t rely on that alone before sticking your hands in there. Plus, it only works if the tubes are installed, if you’re testing something with the tubes pulled, those caps will hold a charge for quite a while.

[@karningham2849]

@@xenod1066 dude, why not just give advice if you're taking the time to comment? Snarky as h*ll

[@cuzimamadman]

thanks rob, and thanks for posting! great vid!

[@RSethTV]

Great Video Rob!

[@RoxxHoffner]

Very informative and to the point. Thanks for sharing.. Mighty fine guitar playing as well. That's how my amp used to sound. I repaired a cracked solder joint at the "foot switch" connector, but now I find there's something not right with the far right, small(pre-amp) tube. A friend tested my tubes by removing them, then stuck new tubes in thew sockets(1 by 1). That's when I noticed he wasn't quite somber enough to be doing this test. He either bent the pins and/or caused damage at the connection. I realized this when it popped and cut in and out as I barely wiggled the the tube. Are the tube pins worth messing with till they fit again(If that's the only damage) or should I just replace them with new tubes?

[@jetmicbev2006]

hi again..the power tube,yes there is a sound coming out in the drive channel but its very very low i cant barely hear it not unless put my ear close enough to the speaker,i also found out that one of the 2 filament of one of the preamp tube is not glowing..my friend told me it might be the pre amp tube not the power tube because the volume will pass to the preamp section b4 power..is this true..thnk u very mch on ur advice i really appriciate it..

[@robertnewman2864]

Excellent instruction. Can this similar bias adjustment be done on the Fender 410 blues Deville reissue, 2005 model?

[@zoomer51]

first off thx for this tutorial, im planing to get a used 212 deville and that's exactly what i need to check it out in a basic way.. Just a question though since im no tech or whatsoever, you first checked the "general" voltage by putting the red pin close to the bias pot, is there any solder point there since we can't see from that cam angle ? thx in advance for your reply. Cheers from france

[@derzasekolahdidd]

does adjusting "bias voltage" mean the same as adjusting the voltage in "cathode bypass" resistor? And how can we manually figure out the idle voltage/ current?

[@brenfen]

Great video. Should the bias level be set differently for different brands of tubes or is 60 generally a safe bet?

[@zbyszekskibinski]

ok thanks for your comment. all the best mate.

[@LeviSiccard]

hey, i got the american fender hot rod deville 410 from '91. I had to replace the tubes, wich i did but I can't get the bias under 73. The tubes i bought are the electro harmonix 6L6, wihch were recommended by key music, the biggest store in Belgium. and I believe myself that these are pretty nice tubes made by sovtek in russia..

[@MTG776]

Great Video! Is there a Marshall JTM 45 video like this? That would be cool!

[@382002mat]

Thank you for your answer,i'll contact Soldano soon! Great video!!