Help quick Im fucking worried! - Page 2

***Adwex*** · 10-29-2009, 09:46 PM

Quote:

Originally Posted by HOT TUBES 70

And how critical is " biasing " ?? IMO !! To me its even more important than the tubes you run , set to cold - yuk !! set to hot , yah you get lots gain but no warmth
and real tone . It maybe a few extra minutes to do it , but its soooooo worth it !!!!!

I'd love to see a video (or even just audio) demonstration of the differences between cold and hot bias.

MartyStrat54 · 10-29-2009, 10:54 PM

Wow! I feel like I've just been through some sort of major medical emergency. The good news is I lived.

Cathode biased amps...commonly called (in error) fixed bias amps.

The picture of the RCA Fat Boy tubes? I'll take 12 of them...for free.

American Viking · 10-30-2009, 12:17 AM

The tube and bias issue with the Mesa's has it's pros and cons. I'd say for those novice at tube knowledge and no electrical skill it works, only if you buy the tubes from Mesa rated for that particular amp. That also goes without saying, amplifiers are not toys and require some basic knowledge of electricity and electronics to run them properly and have them last.

Where the big negative comes out is that they don't clearly state enough that you have to buy their tubes because only Mesa authorized dealers will have Mesa tubes. Most people just run to a GC and get Groove Tubes since they're always available and the bias will not be correct in the amplifier. Also tone, they don't give you a choice whether you want early or late breakup, and you don't have the option to change tube types either. Mesa tubes are typically more expensive too, as they buy them just like anyone else, then slap their logo on them so you have to pay for a supplier and a middle man. At least Mesa swears they don't use Chinese tubes.

I have a Mesa 400+ bass amp and I buy sets for the amp from Eurotubes. Much better price. If I ever had a Dual Rec (for whatever odd reason) I would definitely put a trimpot in place of the bias resistor. As far as the bass amp, I don't want the headache of biasing 12 output tubes... lol

Wilder Amplification · 10-30-2009, 12:48 AM

Quote:

Originally Posted by American Viking

The tube and bias issue with the Mesa's has it's pros and cons. I'd say for those novice at tube knowledge and no electrical skill it works, only if you buy the tubes from Mesa rated for that particular amp. That also goes without saying, amplifiers are not toys and require some basic knowledge of electricity and electronics to run them properly and have them last.

Where the big negative comes out is that they don't clearly state enough that you have to buy their tubes because only Mesa authorized dealers will have Mesa tubes. Most people just run to a GC and get Groove Tubes since they're always available and the bias will not be correct in the amplifier. Also tone, they don't give you a choice whether you want early or late breakup, and you don't have the option to change tube types either. Mesa tubes are typically more expensive too, as they buy them just like anyone else, then slap their logo on them so you have to pay for a supplier and a middle man. At least Mesa swears they don't use Chinese tubes.

I have a Mesa 400+ bass amp and I buy sets for the amp from Eurotubes. Much better price. If I ever had a Dual Rec (for whatever odd reason) I would definitely put a trimpot in place of the bias resistor. As far as the bass amp, I don't want the headache of biasing 12 output tubes... lol

The beauty of having electronics know-how and a soldering iron is...you've got choices.

Very well stated in regards to the "amplifiers are not toys". I'll also add that "it's not ALL about tone". I've said it before and I'll say it again...there is a definite electrical side that cannot be ignored when it comes to these things unless you wanna kill your amp or yourself. Yet too many choose to ignore the electrical aspect and have a "it's all about what my ears are telling me" attitude.

nofearfactor · 11-04-2009, 08:05 AM

Your amp being 'fixed' bias means jack. I would have a trimpot installed by a qualified tech,I did to both of my MKIV heads and glad I did. With an adjustable bias you can then correctly have them biased every time you replace tubes and to get better tone and longer lifespan on your new tubes. I had my local tech guru do the work on adding the trimpots to my Mesa heads but Jerry at FJA mods did the trimpot mods on my 5150s. Mesa just seems like they want you to always be buying their tubes from them. I prefer to buy my sets from Eurotubes but I sometimes will get preamp tubes from thetubestore.com. I have used Dougs tubes before in the past. I get my Brimar 12AT7s (NOS tubes) from tubemonger.com. I dont have to use them but they came stock in my first 9200 power amp so I keep putting them back in there.

Disclaimer: I'm not an electronics tech. Any post I make about anything is only based on my experiences with gear and limited electronics knowledge. I'm just a musician who has been messing with his gear,since I was 16 in 1985, basically just to try and understand as much about my gear as I can so that I can get the most out of it. I have an experienced tech with over 40 years of experience do all of my amp and electronics work who also tries to help me understand things better. He regularly does work for Clapton,Nugent, Ry Cooder,Rick Nielson,etcetc. I trust him.

10-29-2009, 10:54 PM	#32 (permalink)
MartyStrat54 Senior Member Join Date: Feb 2009 Location: Formerly Phoenix, now north of KC Posts: 2,583	Re: Help quick Im fucking worried! Wow! I feel like I've just been through some sort of major medical emergency. The good news is I lived. Cathode biased amps...commonly called (in error) fixed bias amps. The picture of the RCA Fat Boy tubes? I'll take 12 of them...for free. __________________ MARTY 2009 Gibson Explorer-Hell Raising Machine 1989 Fender Strat Plus USA 2008 Fender Tele USA 2004 Schecter Elite w/DiMarzio's TSL100 with custom 4x12 cab. TSL122 with Man 'O War Speakers. TSL602 #1 with JBL D123 Speakers and 602 #2 with Altec 417 Speakers. "Oh so sweet my friends." DSL401 #1 with Red Fang Speaker and 401 #2 with JBL D123 Speaker. Tubes: Let's just say they are NOS that kick ass.

10-30-2009, 12:17 AM	#33 (permalink)
American Viking Senior Member Join Date: Jan 2009 Location: RICHMOND, VIRGINIA Posts: 1,510	Re: Help quick Im fucking worried! The tube and bias issue with the Mesa's has it's pros and cons. I'd say for those novice at tube knowledge and no electrical skill it works, only if you buy the tubes from Mesa rated for that particular amp. That also goes without saying, amplifiers are not toys and require some basic knowledge of electricity and electronics to run them properly and have them last. Where the big negative comes out is that they don't clearly state enough that you have to buy their tubes because only Mesa authorized dealers will have Mesa tubes. Most people just run to a GC and get Groove Tubes since they're always available and the bias will not be correct in the amplifier. Also tone, they don't give you a choice whether you want early or late breakup, and you don't have the option to change tube types either. Mesa tubes are typically more expensive too, as they buy them just like anyone else, then slap their logo on them so you have to pay for a supplier and a middle man. At least Mesa swears they don't use Chinese tubes. I have a Mesa 400+ bass amp and I buy sets for the amp from Eurotubes. Much better price. If I ever had a Dual Rec (for whatever odd reason) I would definitely put a trimpot in place of the bias resistor. As far as the bass amp, I don't want the headache of biasing 12 output tubes... lol __________________ -I'd rather be a good liver than have one...

11-04-2009, 08:05 AM	#35 (permalink)
nofearfactor Senior Member Join Date: Mar 2009 Location: Hellbillyville Posts: 180	Re: Help quick Im fucking worried! Your amp being 'fixed' bias means jack. I would have a trimpot installed by a qualified tech,I did to both of my MKIV heads and glad I did. With an adjustable bias you can then correctly have them biased every time you replace tubes and to get better tone and longer lifespan on your new tubes. I had my local tech guru do the work on adding the trimpots to my Mesa heads but Jerry at FJA mods did the trimpot mods on my 5150s. Mesa just seems like they want you to always be buying their tubes from them. I prefer to buy my sets from Eurotubes but I sometimes will get preamp tubes from thetubestore.com. I have used Dougs tubes before in the past. I get my Brimar 12AT7s (NOS tubes) from tubemonger.com. I dont have to use them but they came stock in my first 9200 power amp so I keep putting them back in there. Disclaimer: I'm not an electronics tech. Any post I make about anything is only based on my experiences with gear and limited electronics knowledge. I'm just a musician who has been messing with his gear,since I was 16 in 1985, basically just to try and understand as much about my gear as I can so that I can get the most out of it. I have an experienced tech with over 40 years of experience do all of my amp and electronics work who also tries to help me understand things better. He regularly does work for Clapton,Nugent, Ry Cooder,Rick Nielson,etcetc. I trust him. __________________ myspace- http://www.myspace.com/nofearfactor some gear pics- http://community.webshots.com/album/...ecurity=QbSaeN

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