1974 F212 Pick Up Question

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Does anyone know what pick up comes stock on these. It looks like there is Barcus Berry Hot Dot transducers on the bridge. The person I bought the guitar from said it had stock electronics....
 

adorshki

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Does anyone know what pick up comes stock on these. It looks like there is Barcus Berry Hot Dot transducers on the bridge. The person I bought the guitar from said it had stock electronics....

Sounds right for '74, they did use 'em for a short period.
Check with Nuuska, He has a Cutaway version and I think he replaced his Hot Dots, or at least installed something else and bypassed 'em.(?)
 

Nuuska

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Hi

Originally my guitars were without anything. Then I installed two BB Hot Dots on three of them. Later sent them to Guild and they put in those thick compensated saddles with piezo under it plus preamp w vol & tone. Later I ditched the preamps and added soundhole humbuckers. Put in stero jack. Wired humbucker to tip and piezo to ring - both via volume control - since the holes were there. I chose humbucker to be in tip, so I can play it with any guitar amp with regular guitar cord.

Usually I have stereo-plug into two mono-plugs Y-cord so I can process both pups separately. Humbucker gives the body and piezo adds to that. Not really what you would get when recording w decent microphone. But very anti-feedback and suits my fingerstyle playing.
 

Nuuska

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Does anyone know what pick up comes stock on these. It looks like there is Barcus Berry Hot Dot transducers on the bridge. The person I bought the guitar from said it had stock electronics....


Hello

Even that I do not know what you have - but if they are Barcus Berry Hot Dots, they insist to be fed into as high-impedance input as possible. I'd say 1Mohm minimum. After that everything depends on how good they were mounted.

When I bought my first piezos, they came with a piece of clay-like material that you were supposed to use between the guitar and pickup. I quickly realized that it was like having a pillow in front of your vocal microphone. Started using better glues - like contact-glue - the one that you put on both sides, wait for it to dry a bit and press together. Glues almost anything, but the joint is still a bit flexible. So we took the pillow out but still left the cover . . . Advantge was that it could be removed. Finally there was the advice to cast the PU with epoxy. Best possible contact but no chance to move it afterwards. And if location was right, then the sound was best possible, too.

Importance of high-impedance input is that if it is not high enough, it will load the transducer and result is midrange boost wit little bass a and poor highs - suppose this is what some refer as quack.

Good units with high enough impedance are some active DI-boxes and my all-time favourite : MXR Micro Amp - high input impedance w up to 26dB of pure gain - low-impedance output so it can drive practically anything.

Surely there are plenty of others - just haven't looked while my MXR still works fine.
 

adorshki

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Hello

Even that I do not know what you have - but if they are Barcus Berry Hot Dots, they insist to be fed into as high-impedance input as possible. I'd say 1Mohm minimum. After that everything depends on how good they were mounted.

When I bought my first piezos, they came with a piece of clay-like material that you were supposed to use between the guitar and pickup.
Guild installed Hot Dots right into the wings of the bridge covered with little inlays, that was the giveaway of the factory Hot-Dot installation.
Ah, here we go:
IMG_0325.jpg

Another one with plain wood caps:
bridge.jpg


To give the OP a photo frame of reference of how factory installation looked.
:friendly_wink:
The last time I looked into "usability" I discovered there are still few fans out there but they seemed to agree they worked the best with the original Barcus Berry amps (and pre-amp? I forget); it may very well be due to the impedance matching issue Nuuska mentioned.
 
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Nuuska

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Hello

Old thread bump - while searching for something completely different in my workroom last night - I came across these two.

The preamps that Guild put into my guitars.

The National Semiconductors OP AMP LM4250 is powered with +/- 1,5V using two AA-batteries.
According to datasheet it could be run with +/- 9V or even +/- 18V - leading to over 20dB more gain or headroom.

Perhaps I should experiment a little - nothing to loose there , but time.

For those interested - the datasheet is here : https://www.egr.msu.edu/eceshop/Parts_Inventory/datasheets/lm4250cn.pdf




img_3507.jpg
 
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