Tube Amps / Music Electronics
For current discussions, please visit Music Electronics Forum. New: view Recent Searches.
New: visit Schematic Hell!
The sunn still shines online!

Listen to great tunes streaming live right now!

ampage archive

Vintage threads from the first ten years

Search for:  Mode:  

laminated core

7/30/2003 7:26 PM
jj laminated core
was looking at a book on building ignition coils and they said using the laminated core has a faster responce on the flux was wondering if anyone had tried making a core for a pup this way ?????
7/31/2003 11:47 AM

I dimly remember seeing a pic of a blade humbucker awhilde back, with laminations visible in the blades, it was either a Bartolini or a Bill Lawrence. As I recall it was a high output humbucker. Haven't heard one though.
Book Of The Day The Ultimate Tone, Volume III by Kevin O'Connor
Have you ever wondered if there is a better way to build a Bassman, Champ, Plexi, an 800, AC-30, Bulldog or Portaflex? Or you wanted to build an SVT with off-the-shelf parts? How about a master-volume amp that doesn’t change tone with the master setting? Everything you need to know is right here, including: proper grounding techniques, wiring methods, and mechanical considerations. Eighteen chapters cover the “iconic” amps everyone knows and loves, with schematics and layouts for each, along with the technical history of the product. Eyelet-board and chassis-mounted tube socket construction is used throughout, for easy servicing and modding. TUT3 is very accessible even if you cannot fully read a schematic and is a "must have" if you are going to build an amp for your self.

Note: The Ampage Archive is an Amazon Associate site. A small commission is paid to the site owner on any qualified purchase made after clicking an associate link such as the one above.
8/3/2003 8:53 AM
Fred Hammon

I have just finished doing some pre-production prototypes of the Hagstrom(Guild) single coil bass pu used in the '60s. (Starfire basses) It's actually a varition of an old DeArmond guitar pu design.  
This single coil uses steel laminations with low carb. steel pole pieces running through holes in the laminations with bar mags. on either side. The steel lams apparently reduce eddy currents and create some sort of hystersis which stores energy and releases it slowly causing a sort of "soft knee effect" ( I don't really understand this shit) Nice in bass pickups though.  
I'm quoting Rick Turner here:  
"The laminations are important as is the insulating layer of varnish between them, and it's not due to hysteresis (nor hysteria), it's to reduce eddy current losses in the pickup itself. Basically, because the pole piece mass is electrically conductive, the pickup (or transformer, etc.) will develop electrical eddy currents within the pole stucture which run exactly opposite the current generated in the coil, thus cancelling out some of the coil's output. You go solid core with that and you'll decrease the output"  
Anyway, prototype pickups turned out very nice. Sound great. Got thumbs up from the right people. I'd be happy do enter a discussion with anybody about these jewels who's interested. I'm starting production "Full Tilt Boogie" next week. I've had some help from you all here so "Thanks"  
8/3/2003 12:56 PM

i'd like to know more.  
8/3/2003 5:43 PM
Fred Hammon

More about steel laminations in pickups or more about Hagstrom/Guild bass "reissue" pickups?
8/4/2003 1:45 AM

actually both.  
I've never played a guild or hagstrom pickup. and the lamination idea is quite interesting.  
8/4/2003 5:49 AM
Fred Hammon

The Hagstrom single coil used on the Guild Starfire hollowbody basses in the mid to late '60s,(also on their M85 basses) are famous for being what I call the "Love Pups". Jack Casady(J. Airplane)and and Phil Lesh (G. Dead) used them during that period. Rick Turner, Ron Wickersham and "Bear" Owsley tinkered with them a bit and added emitter followers mounted right on the pickup so as not to get any freq. loss due to line resistance and ran it through an onboard powered preamp system. This became the 1'st active pickup. These guys later went on to form Alembic. The pickups, stock, were unbeatable at the time in that they had the widest frequency response of any pickup. "They were the one to beat" Later of course they did.  
If you want the low down on the Voodoo of the whole design I suggest you email Rick Turner himself at Turner Guitars. He loves to talk about them when he has the time.  
I could provide some detailed photos here if I knew how.  
   Page 1 of 4 Next> Last Page>>