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Thread: Matchless Chieftan - WTH

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    Matchless Chieftan - WTH

    So this combo came in with low volume and distortion. I checked the bias and was shocked. 70ma per EL34. Plate volts are 430v. So I figured these tubes are toast and put a new pair in. Same result.

    I subbed in an OT, and checked the Rk' s etc... all this only to see on the schematic that this is CORRECT! So...WTH.

    In the schematic it has 24v/270ohm on cathode. 89ma!! At 430v Ra that's 38watts!!

    Please someone tell me there's a reason for this. They have "special" EL34 they use from the factory right? 藍

    http://www.thetubestore.com/lib/thet...-Schematic.pdf

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    I'd think that there ought to be a resistor after C9 and C18 (if I am reading the numbers rightly). As it is, when the master is at zero, V5A and V5B are driving each others' plate resistors in parallel with their output impedances. Seems as though this would compromise the performance at low MV settings.

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    Old Timer Leo_Gnardo's Avatar
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    Quote Originally Posted by lowell View Post
    In the schematic it has 24v/270ohm on cathode. 89ma!! At 430v Ra that's 38watts!! Please someone tell me there's a reason for this. They have "special" EL34 they use from the factory right?
    Not only are the Matchless amps intended for deep pocketed rock (and country) stars, their need for constant maintenance (read output tube changes) keeps them out of reach for ordinary folks. No, there is no "special" EL34. Just a special disregard for real world operating conditions by the designer/manufacturer. Dont'cha know, it's hip to run your output tubes at red plate heat, and put in a new set for every gig. Maybe every song. Carry plenty of spares, plus a pair of oven mitts. Phooey!

    I've tried increasing the cathode resistor but by the time plate current is brought down to a sane level, the output is in deep crossover distortion. Can you tell, they're not my favorite amp?
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    Not to mention, that "Master Volume" is just a courtesy. It was never really intended to be used below "10" anyway...
    All joking aside, it was meant for shaving off a little bit, not getting Rawk in the living room.

    Justin
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    Old Timer Leo_Gnardo's Avatar
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    Quote Originally Posted by Justin Thomas View Post
    Not to mention, that "Master Volume" is just a courtesy. It was never really intended to be used below "10" anyway...
    All joking aside, it was meant for shaving off a little bit, not getting Rawk in the living room.

    Justin
    But dont'cha just luv the way their logo lights up, ain't that special? All the guys in Pelvis Parsley's band got one'a them Matchless amps on the Hootenanny show, I gotta get one too!
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    Senior Member Enzo's Avatar
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    Think of it as a class A amp, and then you ignore the high current.
    Education is what you're left with after you have forgotten what you have learned.

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    Old Timer J M Fahey's Avatar
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    Killer sounding amps, they are what they are, and if you donīt like them, just donīt buy them.
    I do regular maintenance on the few available in Argentina (less than a dozen) and players love them.
    They run so hot that the plastic front panel bends.
    I added a 12V fan fed rectified 6.3V (about 7 or 8 V DC) so they just blow a gentle breeze and owners clip one wire to stop them, claiming "sound is not the same" ... who am I to disagree?

    A common problem is that power tube cathode caps dry up , at least once a year, check that.
    Juan Manuel Fahey

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    Supporting Member The Dude's Avatar
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    One of my favorite guitar tones for a semi-distorted sound is Todd Nichols (Toad the Wet Sprocket), who plays a DC30.
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    Old Timer J M Fahey's Avatar
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    Quote Originally Posted by TimmyP1955 View Post
    I'd think that there ought to be a resistor after C9 and C18 (if I am reading the numbers rightly). As it is, when the master is at zero, V5A and V5B are driving each others' plate resistors in parallel with their output impedances. Seems as though this would compromise the performance at low MV settings.
    Thatīs the idea.
    Both plate signals mix ... out of phase.
    When MV pot is set to 0 ohms, combined output is also 0 VAC.

    Even if it were not, same signal drives both power tube grids ... which again are out of phase so they cancel whatever small signal *might* have survived.

    "Brilliance" control does the same, but at high frequencies ... and itīs just the 60 years old VOX "Cut" tone control.
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    Juan Manuel Fahey

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    Quote Originally Posted by J M Fahey View Post
    Thatīs the idea.
    Both plate signals mix ... out of phase.
    When MV pot is set to 0 ohms, combined output is also 0 VAC.

    Even if it were not, same signal drives both power tube grids ... which again are out of phase so they cancel whatever small signal *might* have survived.

    "Brilliance" control does the same, but at high frequencies ... and itīs just the 60 years old VOX "Cut" tone control.
    I understand the concept - it's how the level control on a Leslie 122 works. It just seems odd to me to load down the PI so much. A resistor in series with each leg should not affect the phase cancellation, just ease the load on the PI.
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    Old Timer Leo_Gnardo's Avatar
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    Quote Originally Posted by The Dude View Post
    One of my favorite guitar tones for a semi-distorted sound is Todd Nichols (Toad the Wet Sprocket), who plays a DC30.
    I wonder if he got his semi-distortion by dialing down the bias current with a bigger cathode resistor, and we're hearing krossover krunch. Not a bad solution, if you like that tone.

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    Supporting Member Chuck H's Avatar
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    Quote Originally Posted by Leo_Gnardo View Post
    I wonder if he got his semi-distortion by dialing down the bias current with a bigger cathode resistor, and we're hearing krossover krunch. Not a bad solution, if you like that tone.
    You can get a lot cooler than idling a 25 watt tube at 38 watts and still avoid crossover distortion. That's just ridiculous. Juan reports that players love the sound of these Easy Bake Ovens though and I guess anything done to cool them off would be sacrilege.?. Nothing clever to say. Just shaking my head. If it were "my" amp I'd cool it off.
    "I've heard magic defined as "a technology you don't understand". By that aphorism, the folks in this forum are practicing wizards, able to summon AND control the lightning demon, and make charms to allow others to use the demon in certain ways." R.G.

    "...less ear-friendly but handy for jazz." Leo_Gnardo

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    Old Timer J M Fahey's Avatar
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    This is one of my customers, listen and judge for yourself:


    by the way, this is not Rock, Blues, Pop, etc. but one of our popular Folkloric songs, just played with electric instruments.
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    Juan Manuel Fahey

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    Old Timer Leo_Gnardo's Avatar
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    Quote Originally Posted by J M Fahey View Post
    This is one of my customers, listen and judge for yourself:

    by the way, this is not Rock, Blues, Pop, etc. but one of our popular Folkloric songs, just played with electric instruments.
    Kool, they got the blues in Argentina! Can't argue with his tone nor playing. Do I see an AKG C-12 on the kick drum? Holey crow - spare no expense!
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    Supporting Member Chuck H's Avatar
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    Quote Originally Posted by J M Fahey View Post
    This is one of my customers, listen and judge for yourself
    Sounds amazing! Great tone. Great playing. Great voice too and nice arrangement and performance overall You don't need to qualify genre on that clip because the artists seem very good at bringing a more contemporary sound to the work. Fortunately for him modern el84's are pretty good with excess current (and don't I enjoy that myself!). But WRT el34's as above I would be (have been) more concerned about modern offerings.
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    "I've heard magic defined as "a technology you don't understand". By that aphorism, the folks in this forum are practicing wizards, able to summon AND control the lightning demon, and make charms to allow others to use the demon in certain ways." R.G.

    "...less ear-friendly but handy for jazz." Leo_Gnardo

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    I won't fit anything other than new-production tubes to Matchless amps. They don't last long at all and I got bitten years ago by fitting expensive NOS and having them come back after three months.

    The killer with these amps is studios leaving them switched on all day long unplayed and not putting them in standby between sessions, or even takes.

    Another problem is those tube socket sleeves with the Nomex (or whatever) lining. They cause the base to overheat. I had an amp with an arced socket and when I replaced them got rid of the sleeve and installed a regular bear-trap retainer. I noticed on the last tube swap the bases hadn't discoloured anywhere near as much.
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    Old Timer J M Fahey's Avatar
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    This player, Ricardo Mollo, always had a good ear for tone, and mixes/matches whateverīs needed to get it, just doesnīt follow "fads", only trusts his ears.

    His earlier setup, with which I could not complain, was classic Fenders, "any" Fender as he put it, in fact on every US trip he brought back a couple silverface Bandmaster heads because they were: tube - Fender - simple - available dirt cheap at pawnshops or second hand at standard Music Shops just because they were "the less desirable" ones, since they carried no "fairy dust" , "no Guitar God used them", played full blast so distortion comes from them, each head driving a Marshall 4 x 12" , rewired for 4 ohms to match heads, the whole shebang pushed by an 80īs TC Electronics distortion pedal.

    End result was liquid, "clean" distortion courtesy of overdriven Fenders, forward sounding Celestion sound, and looooonnnnnnggggg sustain courtesy of that pedal, a killer combination.

    Two local legends apply to his setup:

    1) he was going through one of the "big" NY shops (Mannys, Sam Ash or Alexander) and he asked for a Metal Zone pedal, then just out of the oven and all the rage, but store owner after hearing him play told him: "forget it, kid stuff, just try this one" and gave him the TC Electronics instead.

    2) much later, when he got into Matchless and found them hard to get, they were out of production and in any case never there were many of them, when he saw through the Net that somebody was selling the 15W one in Florida, a few miles away from Miami.
    He grabbed his passport and leather jacket, went to the airport and picked the first Miami bound flight (mind you, some 14 hours away), picked a taxi at Miami airport and went to sellerīs home who couldnīt believe his own eyes.
    Tested and payed for it, grabbed the handle and went back to Miami airport, where he had some trouble with DEA or Immigration; they "somewhat suspected" a Rock type guy who travelled 6000 miles, **no luggage** and with cash in his pocket, stayed only for 4 hours and travelled back "with a package".
    Of course everything cleared up in a few minutes
    Juan Manuel Fahey

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    Old Timer Leo_Gnardo's Avatar
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    Quote Originally Posted by J M Fahey View Post
    back to Miami airport, where he had some trouble with DEA or Immigration; they "somewhat suspected" a Rock type guy who travelled 6000 miles, **no luggage** and with cash in his pocket, stayed only for 4 hours and travelled back "with a package".
    Of course everything cleared up in a few minutes
    Yeh, the "goods" from South America move in the other direction. "DOH!" That's our gummint, working hard as they can.

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    I don't know what it is, but I always get stopped at the airport when carrying packages marked 'Tractor parts for export'.
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    Supporting Member Chuck H's Avatar
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    Quote Originally Posted by Mick Bailey View Post
    I don't know what it is, but I always get stopped at the airport when carrying packages marked 'Tractor parts for export'.
    That's funny. Easily confused people (most of us) in positions of authority can seem even more ignorant than they actually are

    I worked a job in Palo Alto, Ca. with a trim carpenter from North Carolina. The general flew him out because he had game. Had some vintage tools and fabricated many custom tools. He told me that when he flew in he had his special tools in a five gallon bucket with the lid duct taped on for extra security. He intended to carry it onto the plane. Security told him "No way. You need to check that." His response was "What!?! It's tools! It's not like it's a bomb or anything!"...

    He didn't fly that day
    "I've heard magic defined as "a technology you don't understand". By that aphorism, the folks in this forum are practicing wizards, able to summon AND control the lightning demon, and make charms to allow others to use the demon in certain ways." R.G.

    "...less ear-friendly but handy for jazz." Leo_Gnardo

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    Old Timer J M Fahey's Avatar
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    Oh, a friend was stopped at a Brazilian airport, they pulled him from the plane, dragged him to the luggage inspection X Raym,achine and pointing at the screen told him: "explain that loaded pistol in your luggage" ... it was a battery powered drill with a kludged battery pack filled with "1/3 AA" NiMh batteries he got for free at his job.
    Ok, ok, they vaguely looked like .45ACP cartridges and were inside the handle.
    Oh well, joys of 1984.

    Just remembered: for Ricardo Mollo, being 100% Sicilian stock didnīt exactly help him look like a "safe" passenger.
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    Juan Manuel Fahey

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    Supporting Member Chuck H's Avatar
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    Ok. Since we're a little sideways already...

    My customer that travels international is sort of known for being a hot head. Big, bald, tattoos and a leather vest. Very much a biker look. After 911 and the new airport security measures they stopped him at the X-ray for his grooming kit. They wouldn't let him carry it on because there was a pair of nail clippers in there!?! He went off on the security officer saying something like 'What am I gonna do with these, nibble someone to death!?! Do you know what I could do to you with a pen!?!' He spent the next two hours in the security directors office and had to take a later flight.
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    "I've heard magic defined as "a technology you don't understand". By that aphorism, the folks in this forum are practicing wizards, able to summon AND control the lightning demon, and make charms to allow others to use the demon in certain ways." R.G.

    "...less ear-friendly but handy for jazz." Leo_Gnardo

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    Used to work on a Chieftain for this one wealthy guy like every six to eight months.

    thing ate tubes like crazy.

    I built one for a friend out of a Traynor Reverb amp.
    It didnt run nearly as hot and still has the same EL34's from over ten years ago.
    The same 6CA7's it came stock with from the 70's!

    Built a Clubman for myself out of stuff a guy gave me.
    Changed the preamp to more of a Marshall 18w and am running a pair of old 6K7's I found.
    It runs kinda hot, but not as bad as a Chieftain.
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    Better Tone thru Mathematics bob p's Avatar
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    Juan, that tone is HUGE. but looking at 2:49 it doesn't look like he's plugged straight into the amp, so I'm not sure that the chieftain abusing a pair of EL34 can take all of the credit for that tone. I don't know what he's got on the floor, I don't recognize most of the pedals. my best guess is that there's a fulldrive down there, and I have no idea what those other pedals may be. who knows what's really in the signal chain, but my ears think there's some transistor edge in that tone.
    Last edited by bob p; 10-14-2017 at 04:37 PM.
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    Supporting Member Chuck H's Avatar
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    Quote Originally Posted by bob p View Post
    Juan, that tone is HUGE. but looking at 2:49 it doesn't look like he's plugged straight into the amp, so I'm not sure that the chieftain abusing a pair of EL34 can take all of the credit for that tone. I don't know what he's got on the floor, I don't recognize most of the pedals. my best guess is that there's a fulldrive down there, and I have no idea what those other pedals may be. who knows what's really in the signal chain, but my ears think there's some transistor edge in that tone.
    My favorite tones from other players always seem to be a slightly overdriven tube amp with some kind of dirt box up front or a tube amp turned up loud with a clean boost up front to push it into overdrive. "My" rig is a straight up overdriving tube amp with no pedals. But since I designed and tailored it for myself that makes sense. Still I think most favorite recorded distorted tones involve a dirt box and a tube amp. Before I started modding building (going back a long time) my rig was a Marshall and an 80's RAT box. I could happily still use that rig today.
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    "I've heard magic defined as "a technology you don't understand". By that aphorism, the folks in this forum are practicing wizards, able to summon AND control the lightning demon, and make charms to allow others to use the demon in certain ways." R.G.

    "...less ear-friendly but handy for jazz." Leo_Gnardo

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    Supporting Member Chuck H's Avatar
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    From the original post. I don't remember noticing it the first time around.

    Quote Originally Posted by lowell View Post
    WTH is it there for and where did it come from?

    EDIT: Apparently it translates as "blue" or "indigo plant" or could be a surname.
    Last edited by Chuck H; 10-15-2017 at 02:41 PM.
    "I've heard magic defined as "a technology you don't understand". By that aphorism, the folks in this forum are practicing wizards, able to summon AND control the lightning demon, and make charms to allow others to use the demon in certain ways." R.G.

    "...less ear-friendly but handy for jazz." Leo_Gnardo

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    Old Timer J M Fahey's Avatar
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    Quote Originally Posted by bob p View Post
    Juan, that tone is HUGE. but looking at 2:49 it doesn't look like he's plugged straight into the amp, so I'm not sure that the chieftain abusing a pair of EL34 can take all of the credit for that tone. I don't know what he's got on the floor, I don't recognize most of the pedals. my best guess is that there's a fulldrive down there, and I have no idea what those other pedals may be. who knows what's really in the signal chain, but my ears think there's some transistor edge in that tone.
    I already said that in post #17
    the whole shebang pushed by an 80īs TC Electronics distortion pedal.
    I have 2 theories to explain some killer sounds out there, which lots of people often try to clone unsuccessfully, even when the truth is plainly visible, just misinterpreted:

    1) the **oooolllldddd* door theory: imagine this old door at an old house, along the years said door has been painted: blue - red - green - blue - brown - green.
    The million dollar question: what colour is that door? .... green of course, the last paint layer rules.
    If door is chipped you will have glimpses of the earlier colours, but the main one is green, the last one.
    By the same token, if you use various distorting stages in your signal chain, but the last one is balls to the wall driven power tubes, going unmolested straight into good speakers, your sound will be "tube", no matter how much sand you used earlier.
    2 examples:
    * Jimi Hendrix distortion pedal was *awful* buzzy nasty Fuzz Face ... yet he had incredible liquid sustain thanks to the overdriven Marshalls.
    Funny things happen when noobs try to use a Fuzz Face into a "Marshall" ... a 30W valvestate on 3 (any louder and the cops come) ... so ugly is the sound that Fuzz Face isnīt used any more.
    * similar thing happens with revered Tube Screamer.
    Killer sound driving Fenders to death (similar to Ricardo Mollo recipe) , not so cool on its own (although way better than FF)
    * Krank Distortus Maximus: killer driving an overdriven Krank full tube amp, nasty buzzy on its own.
    Juan Manuel Fahey

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    ha!!! Y'all are crackin' me up.

    Long story short. Replaced the Rk's with 470ohms. Put them around 45ma. Still hot IMO, but within spec. Amp SOUNDS FINE. Oh and BTW both speakers are blown, oddly enough.

    Chuck, that symbol was a on my phone. It turned into an Eastern/Asian symbol after posting
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    Better Tone thru Mathematics bob p's Avatar
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    thanks, Juan. can you clarify what those other pedals are in his signal chain? since you know the guy, maybe you can find out, or maybe there are some pedal users here who will know those things. me? i've been out of the pedal thing for so long that i don't even have a clue. i haven't bought a pedal since the 20th century. my only interest is out of curiosity. i seriously dig that tone.

    (I'm showing my age when I say that I dig it, rather than calling it dope.)
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    Old Timer J M Fahey's Avatar
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    Will ask when I see him at some show, or his stage hands bring something into the shop, but he changes pedals *often* in any case.

    The main point anyway is to have a standard Tube amp driven to hell so *it* supplies main distortion, and a somewhat neutral didtortion box driving it.
    So yes to that old TC Electronics pedal, an MXR Distortion+ , a Blue Screamer, maybe a RAT if you set "filter" flat (it can become a ball of mud if you overdo it) , probably not a Marshall Guvīnor or any of its derivatives and definitely not strong flavoured pedals such as Big Muff or any Fuzz.

    And use good to excellent speakers, he uses basically Celestions, either standard 4x12" boxes or whatever Matchless fit there.
    Donīt know whatīs inside the little 15W one, but standard muscle in the DC30, which pushed him upwards thanks to a very favourable Guitar Player shootout was a Celestion Greenback and G1230H , which turned out to be a winner combination.

    Matchlessī Sampson was trying to recreate original VOX AC30 sound, but he could not get his hands on a pair of Celestion Blue because they had not been reissued yet and originals were unavailable or horribly expensive, same thing, so he tried a ton of combinations to find which came closest.

    Best was what I posted above, with the added twist of degooping: he brushed speaker edge with some acetone and wiped away with cotton balls or toilet paper the sticky solution as much as he could.
    I *guess* as a side effect he was *aging* those speakers.

    Point is, and I remember reading that on the paper magazine way back then , that said shootout was about "2 x 12" combos" and part of the testing was plugging all of them into a standard Marshall 4 x 12" .
    *All* combos improved sound (compared to internal open back 2 x 12") which is not surprising, **except** Matchless DC30 which "had same quality on its own as the full 4 x 12" cabinet" which is nothing short of impressive.
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    Juan Manuel Fahey

  31. #31
    Better Tone thru Mathematics bob p's Avatar
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    are those Matchless combos open-back or closed-back? nobody ever shows the back side of a Matchless, Matchless doesn't say on their website, and I've never seen one in person.

    their site does refer to the preferred pairing as a G12H30 with a Greenback with some "proprietary treatment" which if I had to guess is nothing more than de-doping the surrounds.
    "Stand back, I'm holding a calculator." - chinrest

  32. #32
    Senior Member Enzo's Avatar
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    When one of our stored we serviced for carried the Matchless, I was told they took the new speakers and pounded on the magnets with a mallet to reduce the magnetic charge in them.

    matchless-ch-112-chieftain-338861.jpg
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  33. #33
    Better Tone thru Mathematics bob p's Avatar
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    Quote Originally Posted by Enzo View Post
    When one of our stored we serviced for carried the Matchless, I was told they took the new speakers and pounded on the magnets with a mallet to reduce the magnetic charge in them.

    Click image for larger version. 

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    Mallets?!? WTF?!?

    (there's a "WTF" just for you, rjb. )
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  34. #34
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    Quote Originally Posted by Enzo View Post
    When one of our stored we serviced for carried the Matchless, I was told they took the new speakers and pounded on the magnets with a mallet to reduce the magnetic charge in them.
    Something I've meant to ask Juan about, but keep forgetting.
    Why don't we just partially degauss speakers rather than using power attenuators? Something about the sound must fall apart if the gauss level goes too low?
    How does Eminence modulate the flux density in their FDM speakers?
    Certified Dotard

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    Old Timer J M Fahey's Avatar
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    Quote Originally Posted by g1 View Post
    Something I've meant to ask Juan about, but keep forgetting.
    Why don't we just partially degauss speakers rather than using power attenuators? Something about the sound must fall apart if the gauss level goes too low?
    How does Eminence modulate the flux density in their FDM speakers?
    Notice some tried and it didnīt catch on.
    2 problems:

    1) degaussing definitely lowers sensitivity, no doubt about that, but not smoothly across the range.
    Same as installing a corolla engine in a fully loaded 18 wheeler truck, you will lower maximum speed but you will *murder* acceleration.

    The speaker becomes "slow" (literally), muddy, loses treble, bite, attack.
    Also loses damping so you get a boomy "single note peak" at resonance, because it becomes underdamped.
    Which in brochure language is described as "smooth" , "warm" , etc.
    It definitely is not "the same sound but at lower levels" by any means.

    2) power handling decreases dramatically.
    If you think about it, voice coil handling is puny, just a small 2 layer coil of fine wire (typically around 0.16 to 0.22mm) wound on a poorly conductive thin sheet plastic or paper bobbin.
    Easy to burn with a few Watts if laying static on a table ... or inside an unmagnetized speaker.

    Yet Voice coils live standing tens or over 100W because they shake violently all the time, air around them is turbulent (and thatīs an understatement) , VC is 0.1mm to 0.2mm away from a massive (1 to 8 kilos magnetic structure)
    FANE measured the turbulent air conductivity and found it "close to silver" , go figure.

    So you have a speaker which stands, say, 60W continuous, any waveform including squarewave, you drive it with a 30W RMS amplifier which can give you some 50W RMS squarewave fully overdriven (not the exact double because power supply drops something) ... so far so good.

    Now you attenuate it by 10 dB ... and you drive your amp balls to the ball (thatīs the point) ... still 50W RMS squarewave, besides sustain and feedback make your notes, specially power chords last longer ... but speaker voice coil now stands, say, 30W RMS because ventilation is poorer; by definition an accident waiting to happen.

    Worst is that attenuation range isnīt that much, will never turn a Club/garage amp into a bedroom one.

    I find conceptually better to add a resistive attenuator and let a big, robust (and inexpensive) resistor take the onslaught.

    Sound will also change, in fact it will probably appear harsher (Fletcher Munson), but in any case thatīs easier to handle.

    Never opened one, but I guess the Eminence speaker adds some variable gap or separates 2 steel pieces or adds a steel ring "bypass" , something to lose magnetic density **at the VC gap** ; the ceramic magnet is a "strong/square" material and canīt be altered itself .

    Personally find "best" the variable +V system, which leaves everything exactly the same, just makes amp less powerful.
    And second best the Ultimate Attenuator, which passively loads and reamps but in the least intrusive way.
    lowell, g1 and The Dude like this.
    Juan Manuel Fahey

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