Why use the 6-7-8 side of a 12ax7 for the 1st gain stage?
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Why use the 6-7-8 side of a 12ax7 for the 1st gain stage?
Hello! Been looking at Dumble schematics and I noticed that they all go to the second side of a 12AX7 for the first gain stage. Why not the 1-2-3 side first? I also saw this scheme in some Fender schematics I was looking at.
Last edited by titser_marco on Wed Sep 23, 2015 5:11 pm, edited 1 time in total.
Re: Why use the 6-7-8 side of a 12ax7 for the 1st gain stage?
Not OCD?
Ryan Brown
Brown Amplification LLC
Brown Amplification LLC
Re: Why use the 6-7-8 side of a 12ax7 for the 1st gain stage?
Most likely it has to do with the orientation of the V1 stage with respect to the input connection.
Ryan Brown
Brown Amplification LLC
Brown Amplification LLC
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Re: Why use the 6-7-8 side of a 12ax7 for the 1st gain stage?
Marco, there is ALOT of information on this site and it is all available using the search function. Most of your recent questions have been asked and answered many times. I suggest using the search because you'll end up with more information then you'll get by re-asking. Many of the topics are detailed and full of good information. Also, IMO, the best years of TAG are over. The activity has dropped and older threads are likely to contain better information than what will be generated currently. No offense to any of the current members. There is just less activity IMO.
Electronic equipment is designed using facts and mathematics, not opinion and dogma.
Re: Why use the 6-7-8 side of a 12ax7 for the 1st gain stage?
It's supposed to be a bit better on the noise floor...and I believe when you see a schematic without pinouts, it is the "a" section. I would think the 'a' section would be pins 1,2, and 3, but it's my understanding that that is the 'b' section. Please correct me if I have this wrong.
Re: Why use the 6-7-8 side of a 12ax7 for the 1st gain stage?
RCA referred to pins 6, 7, and 8 as section 1.
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- gui_tarzan
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Re: Why use the 6-7-8 side of a 12ax7 for the 1st gain stage?
That's my opinion as well. If you look at the layout of an original Fender it makes sense.Garthhog wrote:Most likely it has to do with the orientation of the V1 stage with respect to the input connection.
--Jim
"He's like a new set of strings, he just needs to be stretched a bit."
"He's like a new set of strings, he just needs to be stretched a bit."
Re: Why use the 6-7-8 side of a 12ax7 for the 1st gain stage?
As its a guitar amp, yes.Garthhog wrote:Not OCD?
He who dies with the most tubes... wins
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Re: Why use the 6-7-8 side of a 12ax7 for the 1st gain stage?
Thanks for indulging my question, guys!
Re: Why use the 6-7-8 side of a 12ax7 for the 1st gain stage?
The search function of tag returns so many results even when "And", "Or". and "Not" are used that I find it near useless. I once asked for a sticky to help me as well as newer users with the function but it came to naught.vibratoking wrote:Marco, there is ALOT of information on this site and it is all available using the search function. Most of your recent questions have been asked and answered many times. I suggest using the search because you'll end up with more information then you'll get by re-asking. Many of the topics are detailed and full of good information.
And I agree that the TAG days are numbered. I'm afraid that the hack (and the inability of the administrators to deal with it effectively) has made it too scary for new users to drop by. If any of the site gurus finds or creates a better site, please let me know.
If it don't get hot and glow, I don't want it !
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Re: Why use the 6-7-8 side of a 12ax7 for the 1st gain stage?
OT: Hey man, it's all cool. I understand why vibratoking pointed me to the search function because indeed, it's a treasure trove. That said, I do agree that the other variables in searching (spelling, conjunctions, me not knowing if the proper term is use "preamp tube section or "preamp tube side") so sometimes to me - given my untrained, self-taught context - asking a question may be best so that I may be pointed out to a discussion that has been had in the past.
In any case, TAG's members are some of the nicest I met on the net. It could be just that you guys are just nice, period, or it could be that the guys here come from a generation when people cared about manners and being decent - not to say you're oldies, but you know what I mean.
Thanks for all the help, this is really great.
In any case, TAG's members are some of the nicest I met on the net. It could be just that you guys are just nice, period, or it could be that the guys here come from a generation when people cared about manners and being decent - not to say you're oldies, but you know what I mean.
Thanks for all the help, this is really great.
- Leo_Gnardo
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Re: Why use the 6-7-8 side of a 12ax7 for the 1st gain stage?
* see below!
Often better to use google instead of the built in search. Funny t'ing about that, but the goog is more powerfuller. Put 'amp garage' in your search term and you'll probably wind up here & see what you need.
And yes it would be good to shake off that PIA "malware site." It's like trying to go to a nice restaurant while wearing prison stripe jumpsuit & leg irons. Scares good people away.
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* EDIT: First paragraph, forget what I said, that was before the "malware" BS. Now Google blocks you from getting thru on searches. What a pile of . . . baloney.
It's nice being "in the Garage" with yez all. But as some have said, this bogus malware alert is doing TAG no good being recognized a site to get good info & gathering new members & also losing those who avoid anything that looks in the least dodgy. Now I AM getting worried.
Often better to use google instead of the built in search. Funny t'ing about that, but the goog is more powerfuller. Put 'amp garage' in your search term and you'll probably wind up here & see what you need.
And yes it would be good to shake off that PIA "malware site." It's like trying to go to a nice restaurant while wearing prison stripe jumpsuit & leg irons. Scares good people away.
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* EDIT: First paragraph, forget what I said, that was before the "malware" BS. Now Google blocks you from getting thru on searches. What a pile of . . . baloney.
It's nice being "in the Garage" with yez all. But as some have said, this bogus malware alert is doing TAG no good being recognized a site to get good info & gathering new members & also losing those who avoid anything that looks in the least dodgy. Now I AM getting worried.
Last edited by Leo_Gnardo on Fri Sep 25, 2015 1:21 pm, edited 1 time in total.
down technical blind alleys . . .
Re: Why use the 6-7-8 side of a 12ax7 for the 1st gain stage?
^ ThisJohn_P_WI wrote:Noise
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Re: Why use the 6-7-8 side of a 12ax7 for the 1st gain stage?
So it seems that noise is the key factor for this, but what sort of noise were they trying to avoid when they designed amps based on this tube? I am asking this in the context of a recent Dumble style build, where my OD channel used V2B(1-2-3) first into the OD pot then out into V2A(6-7-8). I am curious whether it's related to my two current issues with this build:
1. The overdriven sound is a bit too fizzy for my taste.
2. With clean volume, OD, OD Volume, and Master Volume all on 10, I start to hear squealing as I turn the OD Trim control (I used a regular pot, not a trim pot) past 3.
1. The overdriven sound is a bit too fizzy for my taste.
2. With clean volume, OD, OD Volume, and Master Volume all on 10, I start to hear squealing as I turn the OD Trim control (I used a regular pot, not a trim pot) past 3.