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Thread: Lace Alumitone Short Technical Review

  1. #1
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    Lace Alumitone Short Technical Review

    I just purchased the Lace Alumitone Humbuckers set (black).
    Here are the technical details for those interested.

    Each magnet is: 1 3/32" long; 7/32" wide and 1/8" thick ceramic.

    The metal frame of the pickup shell is also the two primary humbucking windings and it is also 1/8" thick. The magnets are glued to a plastic shelf which is also glued to the underside of the alumium shell. The magnets sit about even with the top of the alumium shell. There is very little string pull.

    There is a transformer core that wraps around the alumium coil and core on one side. The other side seems notched to accomodate another similar transformer coil and core which would allow 4-wire traditional pickup coil switching. The transformer coil has two wires that are independent of the ground which allows series switching and phase reversal. The ground is connected to copper tape which is bonded to the aluninum shell under the center strip. This is the ground strip from which I obtained my capacitance measurements (below).

    Each magnet is polarized North and South as it faces the strings.

    The strings only pass over one magnet so the sound is rather "single-coilish" but is brighter as the DC resistance is lower but the inductance is rather high for these resistance values. Here are the critical measured values on my set:
    Pickup 1: 3.40K ohm at 10.70H with 32pf coil lead to ground capacitance, 8.3 kHZ resonance (pickups alone, out of the circuit).
    Pickup 2: 3.42K ohm at 13.24H with 24pf coil lead to ground capacitance, 8.7kHZ resonance (pickups alone, out of the circuit).

    According to Jeff Lace these pickups were designed for 250K pot values for volume and tone, with either .02uF or .05uF tone caps (.05uF is the preferred value according to Jeff). I loaded one of these pickups down to about 150K ohms before I could hear the highs being noticeably cut.

    These pickups sound a lot like active pickups with a low turns count of thicker wire using active electronics to restore the gain lost by the fewer wire turns.

    My plan is to add an EMG BQC concentric bass and treble stacked control and the mid sweep and boost/cut concentric control to see how I can taylor the sound. The input impedance of this BQC module is 200K according to EMG and my examination of the input circuit component values.

    These pickups are very quiet, even when sitting right in front of my computer. This key feature would indicate that they can be activly tone shaped without adding too much additional noise.

    One interesting qualatative observation is that the Alumitones seem to have the upper harmonic structure that is typical of acoustic guitars which electric guitar pickups tend to mask with the sharp roll off past the resonance point. This is relevant of only string harmonics, not wood or body harmonics that is also present in acoustic guitar pickups.

    I hope this answers some questions.

    Joseph Rogowski

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    That inductance reading is weird aint it, for a coil that size anyway. Thanks for the review Joseph.

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    ...

    the inductance is coming off the transformer I think...
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    Senior Member madialex's Avatar
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    I am no expert by a long shot but I am betting the high inductance is due to the amount of aluminum and metal in the PU itself. Just a guess, I imagine Joe G can shed some light on it better than I ever could. The low winds along with the ceramic mags are to keep good high end and the acoustical properties with all that metal and aluminum. They are pretty darn neat though

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    Senior Member madialex's Avatar
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    Well Possum, it looks like it's just you and me for the Christmas thing here.
    I for one am flat broke and am just sitting here killing time till this wretched holiday is over. I feel awful about not being able to get my kids anything at all but I feel keeping the power on and them warm and out of the elements is better than some gifts they wont even care about in a few days or weeks.

    Does this make me a grinch?

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    Not the only ones here, guys!

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    Old Timer Possum's Avatar
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    still here...

    think positive, it attracts money :-) My wife is making good money right now, my health has been dicey last 6 months haven't even played at the jams, miss it alot but not necesserily the cigarette smoke and drunks part of that. Can't drink myself or it'd make me sicker. Getting better though, looks like the new year is going to be good. You got your health, the heat is on, kids fed, you're doing good!

    Those Alumitones suck, have you listened to sound clips? Shrill to the bone, if some guy cranked his amp real loud with one of those things in it I'd be headed for the ear plugs then the door shortly after :-) You think they would have designed in more treble attenuation, sure they look cool but I wouldn't sell anything that edgey myself....
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    Senior Member madialex's Avatar
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    Yeah you are right possum, I just dont like this holiday much. I do understand the true meaning of it but it has gotten so commercial it's saddening. I didn't realise you were as sick as you are. I hope everything turns out for the best with you Possum and you better not up and leave us here Bro. This place wouldn't be the same with no Possum

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    Quote Originally Posted by Possum View Post
    the inductance is coming off the transformer I think...
    I have to think about this. The one-turn aluminum pickup coil is always in the circuit, so in theory one is reading the inductance of the coil, as transformed by the transformer. To read the inductance of the transformer secondary (which faces the amp, not the strings) one would have to open-circuit or remove the one-turn primary. Even so, 10.5 Henry is higher than expected. I'll have to reread the patent.

    Is the measurement correct? Although not stated, I assume that this is 10.5 H at 1000 Hz. Was this measured using an Extech LCR Meter?

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    Alumitone Inductance Measurements

    The Alumitone inductance measurements were done with a Tenma Model 72-6634 LCR meter at 1000Hz.

    I also have a miniature audio transformer with a 1245 ohm secondary coil that measures 16H, so the alumitone inductance is within reason due to the large metal core.

    Joseph Rogowski

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    bbsailor is my screen name: Barnegat Bay Sailor in NJ, located about 35 miles North of Atlantic City.

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    Senior Member Old Tele man's Avatar
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    ...sorry, my error. I deleted my original posting.
    ...and the Devil said: "...yes, but it's a DRY heat!"

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    Lace sucks was a fashion statement when I started working there, I struggled to change that image - they seem to do well on The FDP other then that they take a beating still..

    while working there i discovered something about wire gauge,

    the sensors use 45 46 gauges --

    I ran a test with 43 vs, 42 here with a tele bridge
    one was 6k at 43 the other was 42 at 6k

    people who did not play guitar like the 43 @6k
    people who played liked the 42 @6k

    when I used Sensors on stage while employed there for testing reasons...

    I would receive many compliments on the tone of the Strat from non- players as if it was the best Strat guitar sound they heard --
    on the other hand the players at the same jam HATED the sound..

    I Think I figured out why and told Jeff Lace what it was..

    it was all about ear comfort as a listener - ear muscles seem to not move around uncomfortably from wire 43 at 6k as they seem to do when the receive notes from wire 42 at 6k -- now think of wire 45 & 46 much less muscle movement - easier to listen to for the average music lover -(non musician)

    try this test - do not listen with your ears but feel the muscle movement instead -- the bigger wire cause's more movement - its actually uncomfortable to experience...

    because of this I realized what was going on with Laces skinny wire 45 & 46 and that whole Love em or hate em out poring of approval or harsh criticism that seemed to plague the company - and still does today..

    Players prefer that big tone with girth

    Listeners want less girth and less ear muscle motion

    in a contest like this - The Players win -- but considering the listeners comfort levels is a good thing to keep in mind - especially if your selling your music to the non-playing fans..

    I just wound a wire 43 Strat neck flush/pole to 6.9k and put a old Lace Chrome Dome cover over it and stuck it in the neck of my tele for a test..

    a few Gigs and I see what i think and what non players think..
    Let's all Close shop and Go Fishing!, the heck with everything today!

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    holiday...

    Yeah Xmas if you know the history of it is actually and always was a pagan solstace kind of celebration, the giving of presents, food and drink and dancing. The Christians wanted to stamp everyone with their religion so declared that Dec. 25th was JC's birthday which it never was and actually is unknown. Then there's the fact that JC is composite character and wasn't actually a single person and may not have even existed at all, the story of him is identical to a whole bunch of more ancient stories of gods born of virgin birth etc. etc. So now its about mass consumption and our economic index depends on its existence! Its like the same deal they judge the health of our economy on how many houses or cars are being sold, its totally insane thinking. To me its just another day and a week off from annoying clients and time to catch up on pickups :-) My health is getting better a little at a time, so I'm optimisitic....
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    Quote Originally Posted by bbsailor View Post
    The Alumitone inductance measurements were done with a Tenma Model 72-6634 LCR meter at 1000Hz.
    A 3Kohm series resistance can flummox some LCR meters, but not the Extech. A common effect of added series resistance is that the reported inductance is a factor larger than the truth.

    The Tenma 72-6634 is no longer carried by Tenma, but I did find a specsheet. The test frequency is 250 Hz, not 1000 Hz. Given the lack of any words about the amount of tolerable series resistance, one would doubt that the tolerance is large.

    The Tenma 72-8155, which appears to be the replacement for the 72-6634, does manage 1000 Hz for the 2-19.99 H range.

    The Tenma 72-960 Dual Display LCR meter appears to be a competitor to the Extech 380193 LCR Meter, having the same price and the main functions of the Extech, so the 72-960 may be an alternative to the Extech. The Extech has 12 buttons, versus 8 for the Tenma, but I bet they use the same chip. In any event, they both specify that the dissipation factor cannot exceed 0.5 for the claimed measurement accuracy to be achieved, which means that the DC resistance cannot exceed one half of the inductive reactance at the measurement frequency. Inductive reactance in ohms is computed as 2*Pi*f*L, where f is the frequency in Hertz and L is the inductance in Henrys.

    http://www.mcmconnect.com/tenma/cate...ters&CMP=tenma

    I also have a miniature audio transformer with a 1245 ohm secondary coil that measures 16H, so the alumitone inductance is within reason due to the large metal core.
    It is plausible for an audio transformer to have a 16 Henry winding. What kind of transformer is it? Output, input, interstage, etc?

    A simple experiment is to put a 50K linear pot in series with the transformer secondary, measure the inductance of the composite of winding plus pot, and see how the inductance reported by the Tenma LCR meter varies as the pot is adjusted. If the inductance varies much, the meter will be flummoxed by high-resistance inductors.


    By the way, does anybody recall the Alumitone patent number or numbers?

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    alumatone patent....

    6897369
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    Senior Member madialex's Avatar
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    First thing, I am glad to hear your health is getting better, very good word to hear indeed.

    Yeah the whole Christmas economy thing gets to me. I mean, what would happen if Christmas was banned in the US forever. I guess these big stores and everything else associated with this wretched holiday would fall the fuck apart...I mean why bother to offer good sales and customer service throughout the year when you can half ass it all year and make up for it in spades at Christmas. Walmart comes to mind. I am all for making it as big as you can in any business but dont lose sight of what got you big in the first place.. Thanks to Wal mart doing away with layaway is the main reason my kids did without this year. They said they were losing money??????? How do you do that?? People pick items they want, pay walmart 10 to 20% down and the rest in 3 monthly payments, the customer gets their items everyone is happy right?? How the hell is that a money losing thing??? Oh, maybe it is because if you have something in layaway and that same item goes on sale and you tell them about, your items is discounted to the sale price as well, therefore losing money right?? What about all the exact same items they are selling on the floor at the sale price..... Makes no sense sense to me....

    Just like the Prez harping about all these new jobs, cheeeya right!! If you take a restaurant worker and re-classify them to service workers there ya go,a huge increase in the service sector job total. Just a little creative number working is all that is. No new jobs are actually there, just a shift in a workers tittle.

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    Joe G. Question: It is plausible for an audio transformer to have a 16 Henry winding. What kind of transformer is it? Output, input, interstage, etc?

    I believe it is an output transformer. It has the following numbers on it: 618 629999 then under that number is the following number: 497235. I picked up a box of them surplus many years ago and have been using them as input transformers for experimenting with low impedance pickups. They have a good E core size: .75" wide, .625" tall and has 18 core laminations at 3/16" thick for decent coupling at lower frequencies.

    The low impedance side is 1.4 ohms DC at 8.5mH and the high impedance side is 1.25K at 16H. If my calculations are correct, they are 32 ohms to 50K ohms. Two humbucking coil bobbins filled with AWG30 wire should give me a pretty close match to the low Z side of this transformer with some room to mismatch some for tone adjustment purposes.

    Thanks for the update on my old Tenma 72-6634. I lost the instruction sheet and was guessing at the test frequency. I calibrated it against my General Radio Impedance Bridge a few years ago and it was within 3% to 5% of the GR bridge across most ranges I use it on. The GR does run at 1kHz and can be also run from external signals at different frequencies. I use these to measure fast pulse induction metal detection coils in the 300uH to 500uH range. See my article: http://geotech.thunting.com/pages/me...s/FastCoil.pdf

    I find it faster to use the Tenma than fiddle with nulling of the GR bridge and waiting for it to warm up and stabilize.

    I have been doing some experiments with current sensing transformers and guitar pickups. Do a web search on CSE187L, a low frequency current sensing transformer. I initially used a single loop of AWG 18 magnet wire around a magnet and got a usable output. I even tried a piece of bare AWG 14 from household electrical cable and it works. The thicker the better to increase the current. This transformer has a 1 to 500 turns ratio and is inexpensive ($2.50).

    I placed a scope current probe on the low Z wire and was able to get a peak reading of between 5ma and 10ma depending on how hard I plucked the high E string and how strong a magnet I used. That should give you something to think about!!!

    Thanks for your thoughtful response.

    Joseph Rogowski
    Last edited by bbsailor; 12-26-2007 at 05:28 AM.

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    Senior Member mkat's Avatar
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    Quote Originally Posted by Possum View Post
    Then there's the fact that JC is composite character and wasn't actually a single person and may not have even existed at all, the story of him is identical to a whole bunch of more ancient stories of gods born of virgin birth etc. etc. So now its about mass consumption and our economic index depends on its existence!
    Well said. It says much about the education systems. A little critical thinking goes a long way, doesn't take much to cut through the recycled crap.
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    Quote Originally Posted by Possum View Post
    6897369
    Thanks. That is the one I have that was plausible, but couldn't recall if it was correct. It's actually intended for an acoustic guitar.

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    Joe G.

    Look up patent 5831196 to see the actual Alumitone humbucking design along with other variants.

    Joseph Rogowski

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    Quote Originally Posted by bbsailor View Post
    Joe G. Question: "It is plausible for an audio transformer to have a 16 Henry winding. What kind of transformer is it? Output, input, interstage, etc?"

    I believe it is an output transformer. It has the following numbers on it: 618 629999 then under that number is the following number: 497235. I picked up a box of them surplus many years ago and have been using them as input transformers for experimenting with low impedance pickups. They have a good E core size: .75" wide, .625" tall and has 18 core laminations at 3/16" thick for decent coupling at lower frequencies.

    The low impedance side is 1.4 ohms DC at 8.5mH and the high impedance side is 1.25K at 16H. If my calculations are correct, they are 32 ohms to 50K ohms.
    It does sound like a transistor output transformer. The high-impedance side is actually the primary, and the low-impedance side is the secondary. Not that it really matters - transformers work in either direction.

    Two humbucking coil bobbins filled with AWG30 wire should give me a pretty close match to the low Z side of this transformer with some room to mismatch some for tone adjustment purposes.
    The transformed impedance of pickup coils plus transformer winding should not exceed perhaps one fifth of the impedance of the volume control cum tone control, to prevent undue loading of the pickup assembly.

    Thanks for the update on my old Tenma 72-6634. I lost the instruction sheet and was guessing at the test frequency. I calibrated it against my General Radio Impedance Bridge a few years ago and it was within 3% to 5% of the GR bridge across most ranges I use it on. The GR does run at 1kHz and can be also run from external signals at different frequencies. I use these to measure fast pulse induction metal detection coils in the 300uH to 500uH range. See my article: http://geotech.thunting.com/pages/me...s/FastCoil.pdf
    If your DMM will measure frequency, you can use the DMM to determine the test frequency by hanging it across the item whose inductance is being measured during the measurement. Likewise, one can use a scope.

    I find it faster to use the Tenma than fiddle with nulling of the GR bridge and waiting for it to warm up and stabilize.
    Time for an Extech. What model of GR bridge do you have? I built a Maxwell-Wein Bridge to verify the readings from LCR meters, leading to the selection of the Extech. http://home.comcast.net/~joegwinn/

    I have been doing some experiments with current sensing transformers and guitar pickups. Do a web search on [Triad] CSE187L, a low frequency current sensing transformer. I initially used a single loop of AWG 18 magnet wire around a magnet and got a usable output. I even tried a piece of bare AWG 14 from household electrical cable and it works. The thicker the better to increase the current. This transformer has a 1 to 500 turns ratio and is inexpensive ($2.50).
    This ought to work, and is a cheap way to buy a toroidal half-transformer. The only thing that worried me was the restricted bandwidth - these current transformers are designed for power frequencies, not audio.

    The #18 to #14 wire should be welded or soldered to form the loop, as the voltages are far too low for any mechanical connection method to be reliable.

    I placed a scope current probe on the low Z wire and was able to get a peak reading of between 5ma and 10ma depending on how hard I plucked the high E string and how strong a magnet I used. That should give you something to think about!!!
    If a 7000-turn coil can put a few volts across a 250K pot, the coil is generating 8 microamps. In a 0.250-ohm circuit, this corresponds to 8 amps, so seeing 0.01 amps isn't difficult. And the E string probably doesn't generate the full 2 volts. It takes some kind of storage function for a scope to catch the real peaks as well.

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    Alumitone Patents

    Quote Originally Posted by Possum View Post
    6897369
    While pawing through my files of patents on paper, I found another patent that may be relevant: 5,831,196 (to Khanagov). The drawings look more like the Alumitone, if I recall, but I don't have an example to look at. I read my paper copy on 10 Nov 05, according to the penciled notation. This may be the data of our initial discussion of the Alumitone.

    I see that bbsailor also found 5,831,196, and he has the Alumitone.

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    Joe G. Said: "The transformed impedance of pickup coils plus transformer winding should not exceed perhaps one fifth of the impedance of the volume control cum tone control, to prevent undue loading of the pickup assembly."

    The general rule is that the load impedance (Vol and tone) should be 10 times the source pickup impedance. This optimum ratio is not always possible to attain with pot values ranging from 250K to 1M and the pickups having a high impedance at resonance. As you say, a 5 to 1 ratios is probably more realistic. The big tradeoff is the resonance shift due to coax cable capacitance and amp input additional loading. So, by keeping the pickup impedance to a reasonable level, the natural tone of a pickup can be more approximately maintained, however lower output levels are the consequence unless active buffering is used.

    I have a General Radio Model 1656 Impedance Bridge and a good range of commercial test equipment including scopes, generators, lock-in amplifiers, Boxcar integrator, low noise voltage and current preamps and a variety of specialized probes.

    Your observation about the lowZ input connections being critical is very accurate. I use small tubing about .5" long that matches the diameter of the transformer primary wire size around AWG 12 then use a similar size wire for the primary loop under the strings. Mouser stocks these transformers and it might be worth getting one or two for some experimentation. The secondary resistance of the CSE187L is 21 ohms and I measures it out between 2K and 2.5K ohms impedance. The output impedance value is very sensitive to the input impedance loading/matching. These transformers are very sensitive to being in a low resistance primary circuit so they must be attached directly at the pickup assembly near the strings. This does open the possibility for making a multiple pickup guitar with all volume and tone controls being medium impedance. Then, a Shure microphone matching transformer can be used at the amp to go from a medium Z of 2.5K ohms to 50K into the amp. Les Paul did this years ago.


    Joseph Rogowski

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    Quote Originally Posted by bbsailor View Post
    I just purchased the Lace Alumitone Humbuckers set (black).
    Here are the technical details for those interested.

    Each magnet is: 1 3/32" long; 7/32" wide and 1/8" thick ceramic.

    The metal frame of the pickup shell is also the two primary humbucking windings and it is also 1/8" thick. The magnets are glued to a plastic shelf which is also glued to the underside of the alumium shell.
    What are the dimensions of the aluminum frame/windings? Is it one loop, or two? The intent is to compute the DC resistance of the loop from the geometry, on the assumption that the material is pure aluminum (alloy number 1100).


    Joseph Rogowski
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    http://en.wikipedia.org/wiki/Rogowski_coil

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    Alumitone Physical Dimensions

    Quote Originally Posted by Joe Gwinn View Post
    What are the dimensions of the aluminum frame/windings? Is it one loop, or two? The intent is to compute the DC resistance of the loop from the geometry, on the assumption that the material is pure aluminum (alloy number 1100).


    An illustrious heritage?

    http://en.wikipedia.org/wiki/Rogowski_coil
    Yes, the last name is famous in terms of current sensing coils, but no relation to me that I know of. Maybe back in the old country (Poland) where my Grandfather came from there was a family connection.

    http://lacemusic.com/electric_pickup...tone_specs.php My pickups look like the humbucking version of this with the "Z-like" center section and one magnet under three strings and another magnet under the other three strings.

    Look at the Transbucker specifications in particular the transbucker with 3.4K resistance and 10.5H inductance. http://lacemusic.com/electric_pickup...nsor_specs.php This is the measured specification of my pickups.

    The Transbucker is more similar in electrical specification to the pickups I received than the Alumitone pickups pictured on the Alumitone web page but are listed as having 16.74H at 2.5K ohms. Yes, this is a little confusing????

    My pickups have two individual magnets on the top. There are actually two loops sharing a common center conductor piece (zig-zag). The center section is sort of "Z-like" to accomodate the two magnets. Here are the dimensions.

    Neck to bridge direction dimension: 1 7/16" in the following three sections
    11/32" side conductor piece
    15/16" center Z-like conductor piece
    11/32" side conductor piece
    3/64" gaps between parallel pieces separating center from side pieces.

    Width E to E string direction dimension: 2.5"

    Tall: .75"

    Alumium shell thickness throughout: .125"


    Joseph Rogowski
    Last edited by bbsailor; 12-27-2007 at 02:38 PM.

  27. #27
    Pickup Maker David Schwab's Avatar
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    Quote Originally Posted by Possum View Post
    6897369
    That not it... that's a variation used for acoustic guitars.

    The patents are 5767431 and 5831196. Those are for the Transsensor pickups. The Alumitone doesn't have its own patent but uses the same principal.
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    Senior Member madialex's Avatar
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    Quote Originally Posted by Joe Gwinn View Post

    The transformed impedance of pickup coils plus transformer winding should not exceed perhaps one fifth of the impedance of the volume control cum tone control, to prevent undue loading of the pickup assembly.
    Uhm, Hey Joe, not real sure about all this stuff way over my pea brain but this one little thing I have in bold is bothering me. Are you thinking about electronics and maybe a little something else, Ehh.

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    Old Timer Possum's Avatar
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    why?

    What is the purpose of this one turn pickup with a transformer? Is it the "cool" factor so the thing looks really cool and space age or is there some kind of tone thing I am missing here :-) These pickups don't sound good to me. I don't quite get the point of doing one of these and trying to make it sound better than what Lace did. I also wonder how they patented something that has a previous patent only a couple years earlier using the same idea. Yeah they look really cool but they dont sound very musical to my ears....
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    Quote Originally Posted by madialex View Post
    Uhm, Hey Joe, not real sure about all this stuff way over my pea brain but this one little thing I have in bold is bothering me. Are you thinking about electronics and maybe a little something else, Ehh.
    It's pure electronics. Another way to say it is that if the volume control pot is 250K, the source impedance of the pickup cannot exceed one fifth of 250K, or 50K, and one tenth, or 25K, would be nice.

    So, what is source impedance? It's exactly analogous to the output impedance of an amplifier. If you connect a resistor of this value across the output (of amplifier or pickup), the output voltage will be reduced to one half of the unloaded (open-circuit) voltage.

    So, the primary effect of requiring that the load resistor (the 250K pot in this case) must be a factor larger than the source impedance is to limit the loss of output.

    This light loading has a secondary effect of preserving the spectral balance of the source pickup, as overloaded pickups lose lows, and the overload also increases the width of the resonance, further changing the spectral balance.

  31. #31
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    Quote Originally Posted by Possum View Post
    What is the purpose of this one turn pickup with a transformer? Is it the "cool" factor so the thing looks really cool and space age or is there some kind of tone thing I am missing here :-) These pickups don't sound good to me. I don't quite get the point of doing one of these and trying to make it sound better than what Lace did. I also wonder how they patented something that has a previous patent only a couple years earlier using the same idea. Yeah they look really cool but they dont sound very musical to my ears....
    The larger answer is that it's a radical departure from current passive pickup designs, and as such will have its own tradeoff space, all owned by Lace, who will be riding this for years, with variation after variation.

    I would also mention that ribbon microphones are experiencing a renaissance, driven by the needs of digital mastering, even though ribbon mics are less sensitive than condenser mics. One-turn pickups are the pickup equivalent of a ribbon mic. For instance, US patent 6,434,252.

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    Here is another perspective to expand on what Joe G. mentioned about ribbon microphones.

    Many years ago I built a guitar where I extended the truss rod into the body of the guitar to under the bridge. I used a brass nut and made a special conductive collar to connect the brass nut to the truss rod. This became the common ground return for all six strings and when combined with the signal from each string behind the bridge, made each string it's own independent ribbon-like vibrating element. The current is induced in the string when it vibrates in the presence of a magnetic field. In this case each string becomes the vibrating diaphram of its own microphone and the gets converted to a higher impedance by setp up transformers.

    This direct string pickup, ribbon microphones, and the Lace Alumitone work on principle of low impedance induced current. The result of this current principle is the possibility to use less wire than on a pickup that obtains a high output with many thousand turns of wire and the side effect of having it's own characteristic resonance as well as susceptibility to noise.

    Studying new appraches to making pickups broadens our insights into effecting changes that offer improvements under some circumstances. Any discussions about sound quality are driven by what we have been accoustomed to hear, acceptable musical and tonal quality as well as a technical way to describe and replicate what is pleasing. That is what we do on this forum.

    It is my opinion that pickups that have a wider bandwidth can be equalized easier than pickups that may have some frequency limitations built into their fundamental design.

    Joseph Rogowski
    Last edited by bbsailor; 12-27-2007 at 06:31 PM.
    Corvus likes this.

  33. #33
    Senior Member madialex's Avatar
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    Quote Originally Posted by Joe Gwinn View Post
    This light loading has a secondary effect of preserving the spectral balance of the source pickup, as overloaded pickups lose lows, and the overload also increases the width of the resonance, further changing the spectral balance.
    Please explain what you mean by overloaded Pickup. I really want to figure out some of this stuff but it is all greek to me. Thanks for taking the time to explain this stuff Joe..... Much appreciated...

  34. #34
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    Quote Originally Posted by David Schwab View Post
    That not it... that's a variation used for acoustic guitars.

    The patents are 5767431 and 5831196. Those are for the Transsensor pickups. The Alumitone doesn't have its own patent but uses the same principal.
    Yo, Dave.

    Please visit the Pickupedia patents section at http://pickupedia.info/index.php/Patents

    I have added the incorrect reference for the Alumitone in the hopes that a more knowedgable fellow might log in and fix it.

    (Bwa Ha Ha Haw! My evil plan (AKA Principle of Maximum Laziness) is coming to fruition!)

    -drh

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    Quote Originally Posted by madialex View Post
    Please explain what you mean by overloaded Pickup. I really want to figure out some of this stuff but it is all greek to me. Thanks for taking the time to explain this stuff Joe..... Much appreciated...
    Enough theory. I think an experiment is in order. Take a guitar and wire a 100K resistor across the volume control pot. After adjusting the amp to obtain the same volume, listen and compare to the sound without the 100K load.

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