Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: ginger on January 02, 2019, 10:58:50 am
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I added this cut control to a 5E3 , because I had an unused control spot in the chassis... it does nothing... not that it's just subtle..it does NOTHING. Any thoughts ?
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Matchless calls it a brilliant knob, when I tried I called it useless. try taking the pot/cap out, and replacing it with a switch/cap across the treble cap, so you're switching in a parallel cap with the existing, maybe start at .01uF and decide direction from there :dontknow:
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Thanks... I was trying to find something to match the label on the chassis that says " bass"... I may try your suggestion , or I may just use
a master volume there
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Just going to add a push/pull pot to switch the V2 cathode cap out... I've done that in
other builds... was just looking for something else , but without being too
invasive
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If it does nothing, you’ve probably got an error somewhere. I’ve used that type of cut control in a few builds and it it has a very noticeable effect.
If the amp has negative feedback, it would probably be less effective, but the 5e3 doesn’t, so a wiring or component error is more likely.
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That cut control is for a 5f6a Bassman with a LTPI. Could be different. I attached the Vox cut control schematic, I know it works.
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Yeah I just used the one I did , because Rob Robinette said it was wonderful in a Tweed Deluxe
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I did Ed's vox cut, in an 18 watt, works very well.
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See if I've got this straight .... comparing Ed's schematic to the Robinette layout. The difference is... Ed's cut pot is wired like this.... lug 3 of the pot is wired to the .0047 cap that goes directly to the .1 cap / 220k /and the wire leading back to the grid of 1 output tube . Lug 2 of the pot , ( wiper ) is wired to the .1 cap / 220k / and grid of the other tube . Lug 1 of the pot is connected to nothing .
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See if I've got this straight .... comparing Ed's schematic to the Robinette layout. The difference is... Ed's cut pot is wired like this.... lug 3 of the pot is wired to the .0047 cap that goes directly to the .1 cap / 220k /and the wire leading back to the grid of 1 output tube . Lug 2 of the pot , ( wiper ) is wired to the .1 cap / 220k / and grid of the other tube . Lug 1 of the pot is connected to nothing .
It is not really Ed's, it is a clip I made from the Vox AC30.
Complete schematic attached.
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The circuits are identical. Actually, connecting the wiper to one outer leg is preferred
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Ok.. just replaced the pot , to see if that was the problem.... there's nothing TO this , so simple.. has to work now
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Nope , still nothing, and my board layout is neat... sounds like a really nice 5E3... cut control wired exactly like Robinettes , and what Ed posted . So simple.. I don't get it .
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Show us a pic that clearly shows your actual work.
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Ok... same amp with trem thumping
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Yeah , things are prettier before you start digging for a problem.... the cut pot in on the left , with the yellow mallory .0047 hanging off lug 3 . Nothing connected to the wiper in this picture... been using jumpers , after nothing seemed to make the cut work . I realize this pic can tell you nothing... but here it is
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The wiper must be connected in order for the pot to work.
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Yes.. said that. I've had it connected ... SOLDERED , unsoldered , jumpered...but , thanks for that ,I know it's hard for you to diagnose problems from the shit people send.... can you just come over ? This problem is idiotic... it's like saying , " I have only TWO straight wires , connected to TWO places ", and the wonderful mod does not work. But , really .. thanks
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Sometimes you just have to cut your loses and move on.
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Yeah... there are limits. Good forum though
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So, this treble cut, it's the same as Matchless clubman's "brilliant" ? I'm 2nd guessing myself :think1:
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So, this treble cut, it's the same as Matchless clubman's "brilliant" ?
Same except for the size of the pot. Maybe a 1M pot would help ginger? :dontknow:
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Maybe a 1M pot
I tried that circuit in 2 amps, neither had enough effect on the scope to warrant the solder, and was confirmed by guitar guys. It did "cut" signal some, but only when you dimed the amp, and not enough to have a stage presence. That's why I asked because others seem to have had luck with it? :dontknow:
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I've put that exact circuit in my AC-15 Lite, Dual Lite, and AC-15 amps. I put that same circuit (except using a 1M pot) in my Matchless Lightning. Works fine in all those amps. All those amps have a very similar power amp with LTP PI. I wonder if there is something about the 5E3 cathodyne PI that does not like the cut control?
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I added this cut control to a 5E3 , because I had an unused control spot in the chassis... it does nothing... not that it's just subtle..it does NOTHING. Any thoughts ?
The output impedance for the two outputs connected like that is very small. That means they can drive a pretty healthy capacitive load without losing high frequency response. Therefore, I wouldn't expect your tone control to work with a cathodyne PI.
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>> the 5E3 cathodyne PI
> The output impedance for the two outputs connected like that is very small.
Back up. The first post shows a 5F6a long-tail. But we are really in a cathodyne?? 2deaf has it: the CoD is hard to load-down.
Put your 250K + Cap across the plate load of the stage *before* the cathodyne. Cap to plate so you don't whine about DC voltage under a knob, 0-250K adjustable resistor to ground. 0.005u against the simple ~~39K of the 12AX7 plate cuts all above 900Hz; a hundred K series resistance makes it a shelf instead of a fall-to-zero. Depending how out-back you need to be, you might double or half the cap. 250K Linear makes perfect sense; 500K Audio taper may also be interesting if you like a shelf which is deep but not infinite.
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This place IS the best!
thank you
dave
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Can someone who has time , put this in schematic form
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.
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the CoD is hard to load-down.
You have a cathodyne phase invertor, which as flushed out so far, is hard to effect like you're expecting vs the long tail phase invertor.
when I used that circuit, it was with a Cathodyne 6V6, the other was a inter-stage tranny EL34, both amps are out in the world, both owners did comment, the knob "didn't do much"
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I was actually wanting someone to draw out in schematic form , what PRR was describing
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I was actually wanting someone to draw out in schematic form , what PRR was describing
So why didn't you say that! PRR gave very explicit instructions. Surely you can draw that yourself? Learn to fish.
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This is the treble control from matchless chieftan amp. I'm guessing PRR was describing something like this:
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I was actually wanting someone to draw out in schematic form , what PRR was describing
So why didn't you say that! PRR gave very explicit instructions. Surely you can draw that yourself? Learn to fish.
I CAN... just not sure what he was saying...
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Thanks VMS... that's what I needed
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Cut control works with this schematic , but don't know if it was worth the struggle... almost sounds like a second tone control
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It's no longer a cut control. Now it's a simple treble bleed tone control. At least you got the front panel hole filled.
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Good one
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No... as soon as i found out it sounded like ass... I replaced it with a switch pot... to switch out the V2 cathode cap
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I just really want to thank PRR , for his simple treble bleed ... I'm hunting him down
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Good one
I believe that was your original intent?
I added this cut control to a 5E3 , because I had an unused control spot in the chassis...
PRR (and 2deaf) have always been very helpful with understanding issues that seem to be off the beaten path. I hear he likes Ice House beer. :icon_biggrin:
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Sorry... this time , he gets crap white wine
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I hear he likes Ice House beer. :icon_biggrin:
:think1:
related? :laugh:
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Sorry... this time , he gets crap white wine
It was your idea to try something that doesn't work.
PRR gave you something else to try instead, not his fault you don't like it. Sometimes mods work to someones liking, sometimes they don't and you move on.
We try to be respectful of one another here.
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Sorry... this time , he gets crap white wine
I don't much care for your smart ass attitude, especially when people are trying to help you. And I really don't like your "spoon feed me" mentality, but it's been fun watching you slobber around. Good bye ace!
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Sometimes you just have to cut your loses and move on.
Ok I guess its just me, but I am still cracking up over this as I thought it had a double "cut" meaning. Ok it's just me....
Jim
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I believe I read PRR to write where and what to do, but not exactly the values used. He did write linear, but suggested 250K but did allude to the possible use of a 500k. Maybe try reading about high pass and low pass filters and test a few values. I can assure you a cut control is a tone control as well.
I actually do have 2 tone controls for a tweed deluxe and they are switchable because I like to change speakers. The stock interactive tone is great to me with Greenback or Alnico Blue, the ceramic Jensen is brittle sounding to me.
Sometimes I put in a GZ34 and speaker out to a Altec 417, 8a which will provide a lot more headroom with the 6G3 tonestack. Just have to have a dual 1 meg pot for the main tone control. Probably the most versatile mod I have ever done to any amp.
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Sometimes I put in a GZ34 and speaker out to a Altec 417, 8a which will provide a lot more headroom with the 6G3 tonestack. Just have to have a dual 1 meg pot for the main tone control.
Dual 1M pot?
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Sometimes I put in a GZ34 and speaker out to a Altec 417, 8a which will provide a lot more headroom with the 6G3 tonestack. Just have to have a dual 1 meg pot for the main tone control.
Dual 1M pot?
I am looking for the drawing, but until... the difference between the 2 are the 220K Resistors and cap values, but still 3, 1 meg pots. I just use a DPDT to switch out the resistors, but to switch to another tone control pot to get the stock interactive 5e3 tonestack which I like too.
I found the drawing of modding the 5e3 to 6G3, the switching is simple.
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Really odd reaction... i was joking... I appreciate all the advice... just trying humor... I KNOW I need to figure it out myself. Really frightening reaction from a couple of people .
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You see , i drink crap white wine... a " joke " ?!
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Sorry... this time , he gets crap white wine
I don't much care for your smart ass attitude, especially when people are trying to help you. And I really don't like your "spoon feed me" mentality, but it's been fun watching you slobber around. Good bye ace!
Nice to know that a "Global moderator " can snap so quickly , over nothing
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If you don't like to " spoon feed"... then get off this forum... and, I wasn't " slobbering around ".. i needed help , and i appreciated every reply.
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Thanks to everyone who tried to spoon feed me , and help me "learn to fish" .. and especially to the " Global Moderator".... who's patience , and humor , especially humor , is boundless . I'm drinking Barefoot crap wine now , while working on a lethal amp .
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Wow... Seriously? Ginger you took a shot at someone trying to help you. Whether you were kidding or not, a well placed smiley or a hint that you were joking would have gone a long way. And now instead of apologizing about a misunderstanding, you are telling a Moderator to get off the forum? You should have stopped typing a long time ago before the beer balls kicked in. This was an interesting subject/problem with much to learn. It's a shame it went in this direction.
Jim
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Really odd reaction... i was joking... I appreciate all the advice... just trying humor... I KNOW I need to figure it out myself. Really frightening reaction from a couple of people .
You need to pay attention to what the moderators are saying
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Sorry... this time , he gets crap white wine
I don't much care for your smart ass attitude, especially when people are trying to help you. And I really don't like your "spoon feed me" mentality, but it's been fun watching you slobber around. Good bye ace!
Nice to know that a "Global moderator " can snap so quickly , over nothing
I DID... A "moderator " said... it's been fun watching me " slobber around " ? What IS that ?!!
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I listen to all you guys... i took no " shot "... Look at what the guy said to me.. over nothing... nothing
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So... if "spoon feeding " is getting so painful... he SHOULD go... to preserve his fragile ego
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It can be tough sometimes to tell between a sarcastic joke and a bit of meanness. Imagine if the role was reversed and you took the text of a forum post as an insult. It leads to more insults and infighting. We don’t want that.. we don’t really need that. Ginger you’ve contributed some good posts and I’ve followed them pretty well. The forum is a slower medium of long form communication and is typically more formal, as the posts are more public and meant for archival. I personally understood what you were going for but out of context they can be misinterpreted. The globals are answering a bajillion complex thought intensive questions a day and may not have the focus for remembering the conversation in the same way as others can.
If we can all take a step back and take a deep breath maybe we can salvage things here. I don’t think anyone’s in need of apologizing.. but less aggressiveness would be appreciated.
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All that being said, matchless style output section.. 1M pot seems to be their standard for a MV.. what frequencies are we trying to cut as a LP filter? Looking for advice on what cap value to use.
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Bravo vampwizzard, I have seen many forums devolve into useless sniping. It's the dark side of the wonderful opportunity the Web gives us to communicate in a relatively uncontrolled fashion. I will say that Sluckey is the most giving of any individual I have seen on this or any other tube forums. Just take a look at the assistance he has given countless others on this forum, or check out his Website and see the pains he goes to to communicate to others the details of his projects. If there is a misunderstanding; fine. But lets try to keep the spirit positive, eh?
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Say . . . uh . . . you're not trying to take away my crown as the forum Adam Henry, are you?
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Adam Henry?
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He's related to Sammy O. Brian I think. :icon_biggrin:
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Say . . . uh . . . you're not trying to take away my crown as the forum Adam Henry, are you?
Buddy, you are still tops. Thanks for your impedance input cause I was afraid to say, but I am learning more about impedance.
Ginger, here on the Hoffman forum there are quite a few adults (Excluding Ritchie200 and yours truly) who made their lives in electronics and we have technicians (even me) who need help. Most of the time we consider the work of building amps and modding our own fun stuff.
When I am working on something I do not know about like the impedance of the 5e3 Phase inverter, and someone like 2deaf or PRR suggest something a simple thanks is in order. The info the both provided told me exactly the issue and how to work around it. Starting out as a smartass on forums usually does not work, but after a while Sluckey bitching about me drawing the shit myself and telling me the truth which was I wanted answers without any work. I began to learn, but I did have to realize I was being helped.
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Adam Henry?
What cops call an asshole.
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Thanks Ed for the tip on Adam Henry. I use to have a good friend who was a cop, sadly he's gone now, but I think he had another slang for this - something like Alpha Hotel maybe? Ok, I'll stop now as I don't want to be an HTW.
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Well... i'm sure S. Luckey is very intelligent , and he does a wonderful job , on this forum... but , what he said , was hateful... I don't feel like i deserved his weird wrath
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and... I've seen his posts , over the last few years... He has been like this to others
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I f this S. luckey is above everyone... then he shouldn't stoop to our level
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Festivus is over. Lets get on with the amp stuff. Please.
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He needs to move on
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IF I KNEW the answer... i would not have asked a question... and i won't anymore , as long as S. Luckey , ( keeper of all knowledge ) and a guy who feels like he is not where he wants to be in life , but has to be here , is a "moderator"
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Festivus is over. Lets get on with the amp stuff. Please.
:l2:
"Now for the airing of grevences. I got a lot of problems with you people!" (Georges father.)
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Ginger, you need to stop with the arguing and sniping, now.
Several members have asked you to stop and move on.
The forum owner has also asked you to tone it down and listen to us, the moderators.
I hope you will decide to stop, move past this and be respectful to all the members and all the moderators.
If you can't or wont, then it's probably best if you stop posting anything at all.
It's up to you on how you choose to behave here, but I can tell you, your right at the edge of our patience.
Maybe past it.
I just really want to thank PRR , for his simple treble bleed ... I'm hunting him down
Sorry... this time, he gets crap white wine.
Not funny at all.
You started this with your, according to you, joking around. I called you on it and I'd call you or anyone else here on it.
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ginger is on a 7 day forum ban.