Hi,
I just joined....and also just bought a 2007 360-12 jg. Love the guitar.
I have a question... Does anyone know the inductance, dc resistance, and shunt capacitance of various newer and older higains and toasters? I'm fooling around with a SPICE model of various guitar circuits.
Thanks
toaster/higain inductance
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beatlefreak
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Re: toaster/higain inductance
Welcome to the forum, Wes! Not sure about the inductance and capacitance of the pickups, having never measured them - But the DC resistances are: Toaster ~ 7.4kΩ, Hi-Gain ~ 11kΩ, HB1 ~ 15kΩ.
Re: toaster/higain inductance
Thanks, Kris.
I want toaster sound but I do not want to take my new rick all to pieces or change it in any way. Being new, it has higains.
I'm an engineer that does acoustic transducer design. I used to be an R&D engineer for Shure brothers long ago.
Anyway, I think I have some circuits I have put together that will give an authentic toaster sound even with higains with no modifications. It would be something that plugs into the guitar, then a regular cord plugs into it. It may not even need batteries. Then I can get that great Beatles/Byrds sound easily without any guitar mods! I already found a reference to the earlier toasters....about 1.7 Henries, 7K resistance, and about 120pF stray capacitance. I can measure the highgains on my new guitar, but I might have to unhook a pickup. If someone has the numbers that will save me from having to desolder stuff on the new guitar.
I want toaster sound but I do not want to take my new rick all to pieces or change it in any way. Being new, it has higains.
I'm an engineer that does acoustic transducer design. I used to be an R&D engineer for Shure brothers long ago.
Anyway, I think I have some circuits I have put together that will give an authentic toaster sound even with higains with no modifications. It would be something that plugs into the guitar, then a regular cord plugs into it. It may not even need batteries. Then I can get that great Beatles/Byrds sound easily without any guitar mods! I already found a reference to the earlier toasters....about 1.7 Henries, 7K resistance, and about 120pF stray capacitance. I can measure the highgains on my new guitar, but I might have to unhook a pickup. If someone has the numbers that will save me from having to desolder stuff on the new guitar.
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beatlefreak
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Re: toaster/higain inductance
Les, the biggest difference in sound to overcome will be the different magnets used. Toasters use alnico pole pieces, while hi-gains have a ceramic magnet glued to the bottom of slug poles. Thie yields a completely different magnetic field with differnt tonal characteristics and different resonances.
Re: toaster/higain inductance
Welcome aboard, Les!
For those of us who are not quite so electronically savvy, how does one measure inductance ... or is it a derived quantity?
BTW I have some loose high-gains as well as toasters that I could loan you for some measurements. Let me know.
For those of us who are not quite so electronically savvy, how does one measure inductance ... or is it a derived quantity?
BTW I have some loose high-gains as well as toasters that I could loan you for some measurements. Let me know.
It is better, of course, to know useless things than to know nothing. - Seneca
Re: toaster/higain inductance
Kris,
Yes I expect the field to be different in the pickups, and I wouldn't be changing that. But what i get here as far as the electrical response is huge! The pspice models indicate about 12 db output difference above 5kHz between the two.
That is such a huge difference as to predominate in the sound, I think. That is what I am hearing in the recordings.
I've fooled around with different magnetic fields in pickups I have wound over the years and can certainly hear comb filter effects, but what the pspice shows is more like turning a treble control all the way up or down.
I can and did actually simulate what I want to do by using a very short low capacitance cord and some other components.
The sound I got with the new 360/12 became very very bright and jangly so I know it works.
I guess I'll have to measure the higains to get an exact figure,as no one seems to know the inductance. If I cobble together something i'll post links to a sound file comparing them.
Yes I expect the field to be different in the pickups, and I wouldn't be changing that. But what i get here as far as the electrical response is huge! The pspice models indicate about 12 db output difference above 5kHz between the two.
That is such a huge difference as to predominate in the sound, I think. That is what I am hearing in the recordings.
I've fooled around with different magnetic fields in pickups I have wound over the years and can certainly hear comb filter effects, but what the pspice shows is more like turning a treble control all the way up or down.
I can and did actually simulate what I want to do by using a very short low capacitance cord and some other components.
The sound I got with the new 360/12 became very very bright and jangly so I know it works.
I guess I'll have to measure the higains to get an exact figure,as no one seems to know the inductance. If I cobble together something i'll post links to a sound file comparing them.
Re: toaster/higain inductance
Thanks for the welcome Gary!
Inductance is the constant of proportionality between voltage and the rate of change of current.
You normally measure it with an impedance bridge. I have a very powerful Agilent analyzer in the transducer lab that ought to be able to measure the pickup in the guitar even though there is a series cap and other components. I tried that yesterday, but got about 4.5 H....I don't think that's right. I have to double check the equvalent circuit function and make sure it's programmed right. It should be even able to see things like shorted turn effects from the metal pickup cover!
If I can't get good numbers I might consider having to measure out of the guitar or unhooked.
As a rough guess.... inductance ratio is the square of the turns ratio...so if the toasters are 1.7H 7k and the highgains are 14k, they should be about 1.7 squared or 3.5H. This doesn't account for the growth of the coil diameter though.
Anyway here's what I have modelled up....A custom wound audio transformer and RLC network that could be plugged into the guitar (guitar cord plugs into it) that duplicates hopefully most of the toaster sound. What it does is actually transform the pickup inductance and resistance to a lower value, resulting in lower output with extended highs. It could also be in the guitar with a vol push pull switch.
The problem I am having is the cost. Good audio input transformers are expensive. This one especially so because the primary self inductance has to be about 200 H.....tha's a lot of turns. Oh well, better than the #54 wire we used to use at Shure! But with this....NO BATTERIES! I don't like guitars that need batteries.
Anyway if it's just for me cost isn't so much an issue...just the time required for me to wind the custom transformer.
The cheap way out is to use a source follower FET with a simple eq network.....easy to do and super cheap but needs a battery.
You can also just use a graphic eq and try to crank up the highs. I tried that and it worked some....but very noisy because there is almost nothing up there to boost with the higains.Particularly noisy combined with a compressor.
Anyway this is looking good on paper. I want byrds/beatles sound but don't want to muck up my beautiful jetglow 360-12!
Inductance is the constant of proportionality between voltage and the rate of change of current.
You normally measure it with an impedance bridge. I have a very powerful Agilent analyzer in the transducer lab that ought to be able to measure the pickup in the guitar even though there is a series cap and other components. I tried that yesterday, but got about 4.5 H....I don't think that's right. I have to double check the equvalent circuit function and make sure it's programmed right. It should be even able to see things like shorted turn effects from the metal pickup cover!
If I can't get good numbers I might consider having to measure out of the guitar or unhooked.
As a rough guess.... inductance ratio is the square of the turns ratio...so if the toasters are 1.7H 7k and the highgains are 14k, they should be about 1.7 squared or 3.5H. This doesn't account for the growth of the coil diameter though.
Anyway here's what I have modelled up....A custom wound audio transformer and RLC network that could be plugged into the guitar (guitar cord plugs into it) that duplicates hopefully most of the toaster sound. What it does is actually transform the pickup inductance and resistance to a lower value, resulting in lower output with extended highs. It could also be in the guitar with a vol push pull switch.
The problem I am having is the cost. Good audio input transformers are expensive. This one especially so because the primary self inductance has to be about 200 H.....tha's a lot of turns. Oh well, better than the #54 wire we used to use at Shure! But with this....NO BATTERIES! I don't like guitars that need batteries.
Anyway if it's just for me cost isn't so much an issue...just the time required for me to wind the custom transformer.
The cheap way out is to use a source follower FET with a simple eq network.....easy to do and super cheap but needs a battery.
You can also just use a graphic eq and try to crank up the highs. I tried that and it worked some....but very noisy because there is almost nothing up there to boost with the higains.Particularly noisy combined with a compressor.
Anyway this is looking good on paper. I want byrds/beatles sound but don't want to muck up my beautiful jetglow 360-12!
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soundmasterg
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Re: toaster/higain inductance
Hi Les, welcome to the forum!
I suggest that you visit http://music-electronics-forum.com/foru ... y.php?f=11 as it is one of the best resources on the web for pickups. There are two guys there who are very knowledgeable and are former engineers or something such as that. Joe Gwinn and Enzo. They have posted many thought experiments there about how to acheive various things with the sound and design of pickups. Personally no matter what you do, I don't think you will ever get the exact sound by subbing a gadget in place rather than just changing the pickups as you're trying to emulate metallurgy changes with electronics, but you may be able to get close enough for you to acheive what you want. I can check the inductance of some high gains that I have at home for you but it will be a couple days. You need to get the proper meter, and the one you mentioned may work though I believe the results you previously got were incorrect. You may need to jury rig it. I have one of the Extech 380193 meters which is one of the few meters that will give an accurate inductance reading and also measures ACR and capacitance and Q. This is the same meter that RIC uses. I'll post back here when I have some info for you.
Greg
I suggest that you visit http://music-electronics-forum.com/foru ... y.php?f=11 as it is one of the best resources on the web for pickups. There are two guys there who are very knowledgeable and are former engineers or something such as that. Joe Gwinn and Enzo. They have posted many thought experiments there about how to acheive various things with the sound and design of pickups. Personally no matter what you do, I don't think you will ever get the exact sound by subbing a gadget in place rather than just changing the pickups as you're trying to emulate metallurgy changes with electronics, but you may be able to get close enough for you to acheive what you want. I can check the inductance of some high gains that I have at home for you but it will be a couple days. You need to get the proper meter, and the one you mentioned may work though I believe the results you previously got were incorrect. You may need to jury rig it. I have one of the Extech 380193 meters which is one of the few meters that will give an accurate inductance reading and also measures ACR and capacitance and Q. This is the same meter that RIC uses. I'll post back here when I have some info for you.
Greg
Re: toaster/higain inductance
Thanks Greg.
I measured the higains again on the Agilent. I get 4.7 henry. It's real I think. I was more careful with the eq circuit programing.
Had a long talk with the chief engineer of Jensen about this. He thinks it's doable too.
I don't mind a little skeptism heh....but what it boils down to is if I can measure it....I can duplicate it. Even magnet/metal cover/field/shorted turn stuff. It's just a matter of complexity.
I have the thing designed. Here is the problem....It will be expensive ($100+) if passive. It can be much cheaper if it uses a battery. Either way, it has to be in the cord, near the instrument.
BTW my numbers are saying that if you unwind a higain down to a toaster RESISTANCE it will not sound quite the same. The magnetic circuits have different reluctance. So if the resistance unwound matches the inductance will not, but it will be closer.
Anyway the thing to do is order parts , build it up, and post sound files so we can all hear how close it gets. Wish me luck!
I would like to wait until you can verify with your extech because I have no toasters to test. The last numbers I found were 2.3H, 7.1k ohms, 130pF stray with frequency unspecified. (frequency matters)
I measured the higains again on the Agilent. I get 4.7 henry. It's real I think. I was more careful with the eq circuit programing.
Had a long talk with the chief engineer of Jensen about this. He thinks it's doable too.
I don't mind a little skeptism heh....but what it boils down to is if I can measure it....I can duplicate it. Even magnet/metal cover/field/shorted turn stuff. It's just a matter of complexity.
I have the thing designed. Here is the problem....It will be expensive ($100+) if passive. It can be much cheaper if it uses a battery. Either way, it has to be in the cord, near the instrument.
BTW my numbers are saying that if you unwind a higain down to a toaster RESISTANCE it will not sound quite the same. The magnetic circuits have different reluctance. So if the resistance unwound matches the inductance will not, but it will be closer.
Anyway the thing to do is order parts , build it up, and post sound files so we can all hear how close it gets. Wish me luck!
I would like to wait until you can verify with your extech because I have no toasters to test. The last numbers I found were 2.3H, 7.1k ohms, 130pF stray with frequency unspecified. (frequency matters)
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soundmasterg
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Re: toaster/higain inductance
Hi Les,
You should post the ideas at the Ampage site I listed as some of the guys there would love this subject and you might learn more about it to help you come up with solutions.
Since you know the chief engineer at Jensen, have him redesign their reissue speakers to be closer to the originals. Most of their new offerings are harsh as compared to Eminence or WeberVst offerings because Jensen used the wrong parts for cost reasons.
I can try to test the pickups tonight after work, but they have been in the garage and will be cold and temperature does make a difference in the reading. It would be better if I bring them inside and let them acclimate for a day and test them tomorrow. The Extech tests at 120Hz and 1000Hz. I wish something would test accurately at a higher frequency but we (the pickup community) havn't found something cheap and accurate enough yet.
For pickups I've got the ~7.4k toasters, some ~12k toasters, and some 8k-9k hi gains. I've also got some HB2's I can give you info for if you want them. Its fun to compare the results sometimes and try to coorelate that with the actual sound.
Greg
Thats the problem in that a lot of what we hear can't be measured accurately....But have fun with it!if I can measure it....I can duplicate it
You should post the ideas at the Ampage site I listed as some of the guys there would love this subject and you might learn more about it to help you come up with solutions. Since you know the chief engineer at Jensen, have him redesign their reissue speakers to be closer to the originals. Most of their new offerings are harsh as compared to Eminence or WeberVst offerings because Jensen used the wrong parts for cost reasons.
Of course that will be the case. Alnico magnets have different metallurgy and behavoir than ceramic and rubberized ceramic magnets. The toaster and high gain are put together slightly differently too which makes a big difference mainly because of how the magnetic fields interact with the coil.BTW my numbers are saying that if you unwind a higain down to a toaster RESISTANCE it will not sound quite the same. The magnetic circuits have different reluctance. So if the resistance unwound matches the inductance will not, but it will be closer.
I can try to test the pickups tonight after work, but they have been in the garage and will be cold and temperature does make a difference in the reading. It would be better if I bring them inside and let them acclimate for a day and test them tomorrow. The Extech tests at 120Hz and 1000Hz. I wish something would test accurately at a higher frequency but we (the pickup community) havn't found something cheap and accurate enough yet.
For pickups I've got the ~7.4k toasters, some ~12k toasters, and some 8k-9k hi gains. I've also got some HB2's I can give you info for if you want them. Its fun to compare the results sometimes and try to coorelate that with the actual sound.
Greg
Re: toaster/higain inductance
Cool, greg.
I joined the forum you mentioned.
My only source of possible inacuracy is reading pickups through the series cap and with the tone and volume stuff in place because I am reluctant to take apart such a beautiful Ric!
I see you understand inductance, capacitance, and even resistance is quite frequency dependent. Well, the agilent kinda goes a step further be cause it measures these as functions of frequency in real time!!! It's a wild piece of gear. You can hook a speaker to it and see the electrical impedance functions change as you just walk by!! Similarly it can see eddy currents from alnico, microphonics from covers, damping from rubber, loose windings, and all sorts of things you wouldn't ordinarily be able to see. The only reason I even have it is because it was rented for me by a large corporation so I could develop some very very high power transducers for them. The project is almost done though, so I will only have it a month or two more. I would love to keep it, but it cost $43,000!!! As long as I do have it I hope to get as much information as possible. here it is:
http://www.home.agilent.com/agilent/pro ... =US&lc=eng
So I can get a wealth of information about pickups if they are out of the guitar on the bench. I wish I could keep this box forever. Even Speaker manufacturers don't have one usually.
But...as I said I don't have the pickups. If I was relying on single number parameters it would be best to measure them as close to the loaded self resonance as possible. That's 3KHz. So measuring at IkHz would be most accurate for your meter.
My Spice model gives a sharp 6db resonance at 3.9 kHz for the toaster inductance values I have. For the higains it is much lower...2KHz and change. Huge difference.
And gee, considering what you said about the jensens perhaps I should design guitar speakers for you? I did that sort of stuff at Shure long ago, but I mostly designed Phono cartridges for vinyl. I designed the ML series. #54 wire in the coils. What fun.
Oh also....can I have a vial of artificial blood? I'm a bit anemic.....
I joined the forum you mentioned.
My only source of possible inacuracy is reading pickups through the series cap and with the tone and volume stuff in place because I am reluctant to take apart such a beautiful Ric!
I see you understand inductance, capacitance, and even resistance is quite frequency dependent. Well, the agilent kinda goes a step further be cause it measures these as functions of frequency in real time!!! It's a wild piece of gear. You can hook a speaker to it and see the electrical impedance functions change as you just walk by!! Similarly it can see eddy currents from alnico, microphonics from covers, damping from rubber, loose windings, and all sorts of things you wouldn't ordinarily be able to see. The only reason I even have it is because it was rented for me by a large corporation so I could develop some very very high power transducers for them. The project is almost done though, so I will only have it a month or two more. I would love to keep it, but it cost $43,000!!! As long as I do have it I hope to get as much information as possible. here it is:
http://www.home.agilent.com/agilent/pro ... =US&lc=eng
So I can get a wealth of information about pickups if they are out of the guitar on the bench. I wish I could keep this box forever. Even Speaker manufacturers don't have one usually.
But...as I said I don't have the pickups. If I was relying on single number parameters it would be best to measure them as close to the loaded self resonance as possible. That's 3KHz. So measuring at IkHz would be most accurate for your meter.
My Spice model gives a sharp 6db resonance at 3.9 kHz for the toaster inductance values I have. For the higains it is much lower...2KHz and change. Huge difference.
And gee, considering what you said about the jensens perhaps I should design guitar speakers for you? I did that sort of stuff at Shure long ago, but I mostly designed Phono cartridges for vinyl. I designed the ML series. #54 wire in the coils. What fun.
Oh also....can I have a vial of artificial blood? I'm a bit anemic.....
Re: toaster/higain inductance
Oops.... sorry...Gary is the blood guy. I get easily confused. I am a bit anemic. Can you send me some Gary? Will vampire bats drink it? if so it must be good.... 
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soundmasterg
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Re: toaster/higain inductance
Les,
I've got some info for you here on the toasters and hi gains. It should get you in the ballpark anyway.
Toaster:
DCR = 7.3k
ACR @ 1k = 9.126k
Inductance @ 1k = 1.808 Henries
Q @ 1k = 1.261
1989 4003 neck hi gain:
DCR = 9.05k
ACR @ 1k = 13.04k
Inductance @ 1k = 3.637 Henries
Q @ 1k = 1.763
'80's 6 pole hi gain:
DCR = 10.19k
ACR @ 1k = 13.51k
Inductance @ 1k = 3.037 Henries
Q @ 1k = 1.381
Hope that helps. I don't have any newer hi gains to test at the moment.
greg
I've got some info for you here on the toasters and hi gains. It should get you in the ballpark anyway.
Toaster:
DCR = 7.3k
ACR @ 1k = 9.126k
Inductance @ 1k = 1.808 Henries
Q @ 1k = 1.261
1989 4003 neck hi gain:
DCR = 9.05k
ACR @ 1k = 13.04k
Inductance @ 1k = 3.637 Henries
Q @ 1k = 1.763
'80's 6 pole hi gain:
DCR = 10.19k
ACR @ 1k = 13.51k
Inductance @ 1k = 3.037 Henries
Q @ 1k = 1.381
Hope that helps. I don't have any newer hi gains to test at the moment.
greg
Re: toaster/higain inductance
Ha ha! Our stuff is still in development stage, so no sales (or free samples!) anyway.Les wrote:Oops.... sorry...Gary is the blood guy. I get easily confused. I am a bit anemic. Can you send me some Gary? Will vampire bats drink it? if so it must be good....
I did find one of those Agilent units used for $32,000 ... still a bit pricey!
It is better, of course, to know useless things than to know nothing. - Seneca
Re: toaster/higain inductance
Thanks Greg!
Wow. Lower than I thought. I am getting the urge to unhook a pickup on the ric....obviously I can't get a good read with the tone control circuitry in place. I can read the DCR of the neck pu if I compensate for the two pots in parallel. It's 11.7k.
Is there a way to include pictures here? If so I can plug these into SPICE and show you the frequency response if anyone would like to see.
And Gary....yeah I will hate to lose that Agilent when the project is up. I think I can make one for audio use with a pc and an external op amp based autonulling bridge. The Agilent really is just a pc in disguise...I don't know why the thing costs so much. 0.08% accuracy from one milliohm to 0.5 gigohm and operation to 100 Megahertz+ might have something to do with it.
Wow. Lower than I thought. I am getting the urge to unhook a pickup on the ric....obviously I can't get a good read with the tone control circuitry in place. I can read the DCR of the neck pu if I compensate for the two pots in parallel. It's 11.7k.
Is there a way to include pictures here? If so I can plug these into SPICE and show you the frequency response if anyone would like to see.
And Gary....yeah I will hate to lose that Agilent when the project is up. I think I can make one for audio use with a pc and an external op amp based autonulling bridge. The Agilent really is just a pc in disguise...I don't know why the thing costs so much. 0.08% accuracy from one milliohm to 0.5 gigohm and operation to 100 Megahertz+ might have something to do with it.