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flpete1uw
Advanced Member
Username: flpete1uw

Post Number: 221
Registered: 11-2011
Posted on Monday, December 30, 2013 - 5:11 pm:   Edit Post

I have a 75 Series 1 Bass Short Scale Bass SN# 215 that I’ve been trying to master. The clearance on the 12th fret is .080” (Low but not that low) and the open string clearance to the neck pickup E string is .130” and about .125 on the G. On my newly acquired Stew-Mac String Action Gauge.
According to this post by Dave http://alembic.com/club/messages/16271/16384.html?1107731593 describing pickup heights the distance as a starting point should be ~1/4”. Here’s my dilemma, I used to set the action lower but as stated in the above post the pickup output sounds hot and noisy and I do get a Low end roll off. Raising the action helped some (Much more low end and usable) but I feel it still could be better. My problem is the pickups on this old girl have warped to a point where that is as low in the body of the bass as it will go. (The classic too much pressure on the 2 outside screws causing deformation) In the mean time I reversed the outside screw positions but I don’t have 30 years to correct the problem.
Any ideas on gaining more of the natural low end back. Also I’m somewhat concerned about the ‘magnetic damping' that I may be getting. This Bass has been a Bear of a learning curve for me and I find that any little adjustment makes profound differences in sound. At least the trajectory has been to the good side of better sound.
~Pete
jazzyvee
Senior Member
Username: jazzyvee

Post Number: 3785
Registered: 6-2002
Posted on Tuesday, December 31, 2013 - 2:05 am:   Edit Post

Here is a start if you want to tame the hot output, you can lower the trim pots.
http://alembic.com/club/messages/16271/50896.html?1208917987

There is also a link on that page to the humcancelling procedure if you are getting noise in your output.
Jazzyvee
flpete1uw
Advanced Member
Username: flpete1uw

Post Number: 222
Registered: 11-2011
Posted on Tuesday, December 31, 2013 - 3:41 am:   Edit Post

Jazzy,
Thank you and yes I'm aware of these settings. What I'm referring to is the quote from Dave on his link "The pickups will sound progressively 'hotter' the closer they get to the strings. And noisier: You'll begin to hear string noise, fret rattle a little more." Emphasis on the string and fret rattle. If I¡¦m reading this correctly the distance of the pickup and string is at least partially correlated to string noise? If part of the solution is to lower the output of the pickups it¡¦s certainly worth a try. My problem is, to the best of my knowledge a physical one in that the pickups are warped and I cannot lower them in the Bass cavity any lower. I almost wish I could sand them down to fit ;)
This is the least of the issues for when I raised the action (And improved my playing technique someļ) A lot of the rattle and noise has been eliminated. The main thing at the moment is the Bass roll off which seems correlated to the pickup height.
~Pete
jzstephan
Advanced Member
Username: jzstephan

Post Number: 219
Registered: 1-2012
Posted on Tuesday, December 31, 2013 - 7:59 am:   Edit Post

Is it possible to remove the pickups from the bass, take the adjusting screws completely out of the bass, replace the pickups, and then screw all four screws on the top side of the pickups? That should get you a little lower and having the force evenly applied to reduce the warp. I like my pickups low to get a "woodier" tone.
flpete1uw
Advanced Member
Username: flpete1uw

Post Number: 223
Registered: 11-2011
Posted on Tuesday, December 31, 2013 - 8:15 am:   Edit Post

John,
Thanks for the input and I'm doing just that.
Great minds think alike, minus routing out the Bass (NOT!!) or somehow either unwarping or shaving down the edges of the pickups I'm stuck with this height. The previous owner really let the pickups warp throughout the 38 years of her life.
~Pete
gtrguy
Senior Member
Username: gtrguy

Post Number: 665
Registered: 9-2004
Posted on Tuesday, December 31, 2013 - 10:27 am:   Edit Post

I have an extra set of pickups with the same problem. I wonder what the cure is... They seem to work fine though.



http://alembic.com/club/messages/394/143817.html?1367861650

1

2

(Message edited by mica on January 02, 2014)
lbpesq
Senior Member
Username: lbpesq

Post Number: 5621
Registered: 7-2004
Posted on Tuesday, December 31, 2013 - 10:38 am:   Edit Post

I suspect you could sand the high spots on the bottom down bit?

Bill, tgo
flpete1uw
Advanced Member
Username: flpete1uw

Post Number: 224
Registered: 11-2011
Posted on Tuesday, December 31, 2013 - 11:32 am:   Edit Post

David,
That’s about it, my pickups could be twins. They sound fine as far as I can tell. I went so far as to send them along with the electronics back to the Mother Ship and they checked out fine.
Bill,
Shaving down will be the last resort. Curious how much before you get to the coils / magnet?
What I’m experiencing is that small amounts of adjustments make large differences.
~Pete
sonicus
Senior Member
Username: sonicus

Post Number: 3180
Registered: 5-2009
Posted on Tuesday, December 31, 2013 - 11:54 am:   Edit Post

Perhaps ,it would be prudent to make an inquiry regarding new replacement pickups and leave the original ones as they are. It might be worth it .
flpete1uw
Advanced Member
Username: flpete1uw

Post Number: 226
Registered: 11-2011
Posted on Tuesday, December 31, 2013 - 1:49 pm:   Edit Post

Wolf,
That is an option, if I recall correctly the Series pickups are made to be a matched set. Something to do with the coil windings, even if they are the same # of turns, wire differences could create different outcomes. So each are made to match the other and the Dummy coil. Someone more knowledgeable than me on this please chime in! My Bass’s dummy pickup is loose in the cavity (Old Glue) so I can easily remove it. Curious if all the pickups and spaces for all Series basses stayed the same dimensions through the years. In other words retrofitting new pickups to an old Bass.
~Pete
Wow 7 more hours to a New Year on the East Coast!
jimmyj
Senior Member
Username: jimmyj

Post Number: 493
Registered: 8-2008
Posted on Tuesday, December 31, 2013 - 11:24 pm:   Edit Post

Hey Pete,

A couple comments. First, as you read the rest of that post you pointed to, Dave goes on to say "These effects are not as pronounced with ALEMBIC or other so-called 'low impedance' pickups..."

In my experience the difference of 1/8" in pickup height won't noticeably alter your output level or tone. With Alembic's system it's almost more important where you want to "feel" the pickup with your fingers.

That said, if you really want to recover the small distance lost to your bent corner you should completely remove the screws under the low points and only use the two upper screws to mount the pickup. Or ... just sand off the low points until they are flatter. The coils and magnet have not been effected by this deformation so they are still in the flat area. You should be able to safely remove some material from the lowest point of the bent corner without a problem. Just don't crank down the mounting screws too hard afterwards as this area will be slightly weaker structurally.

That's my 1.5 cents.
Jimmy J
flpete1uw
Advanced Member
Username: flpete1uw

Post Number: 227
Registered: 11-2011
Posted on Wednesday, January 01, 2014 - 4:05 am:   Edit Post

Hi Jimmy,
Your 1.5 Cents is always welcome! Thank you for taking the time to read through this post.
I did see that quote as well and initially that¡¦s what I was hoping to find. However when I readjusted the neck action to a slightly higher setting I noticed a profound gain in low end so my thinking is that if I can get the settings to a basic starting point I can readjust from there. Being from the Studio world I¡¦m big on references, to have settings and a starting point to get back to if things get to weird.
I¡¦m sure part of this is my lack of understanding of the Series electronics. (2 filters 2 Q¡¦s) and the never ending desire to get things right. And also part knowing enough to make things dangerous ƒº
I have the pickups in the way you have suggested and that has helped some. In fact each time I make a small change the sound improves almost exponentially. Maybe getting the pickups to be 1/8¡¨ from the lower level will suffice? And yes I will be careful.
Happy New Year!
~Pete
gtrguy
Senior Member
Username: gtrguy

Post Number: 666
Registered: 9-2004
Posted on Wednesday, January 01, 2014 - 11:07 am:   Edit Post

I think the pickups might have a sort of 'cage' around them in all that epoxy they are made with, but that would not be out at the ears where sanding might take place. I'll probally mount the bent ones I have on a board and see if time might stfaighten them out again.
flpete1uw
Advanced Member
Username: flpete1uw

Post Number: 228
Registered: 11-2011
Posted on Wednesday, January 01, 2014 - 11:48 am:   Edit Post

David,
Best of luck with that. I might suggest it took a long time for this to happen it might take some time to correct. Please keep me posted on your findings.
I'm so close I can taste it, I just don't want to do anything foolish. Interesting thought on the pickup construction sort of a Faraday cage?
~Pete
cozmik_cowboy
Senior Member
Username: cozmik_cowboy

Post Number: 1643
Registered: 10-2006
Posted on Wednesday, January 01, 2014 - 8:54 pm:   Edit Post

Maybe, with the p/ups mounted straight to the body through the lower holes, put the other screws in with a little tension, and see if you can slowly tighten them & flatten the ears back out ( it would, of course, be a long-term project).

Peter
jazzyvee
Senior Member
Username: jazzyvee

Post Number: 3788
Registered: 6-2002
Posted on Thursday, January 02, 2014 - 3:32 am:   Edit Post

Wouldn't it be possible to make the base of the pickup level again using some kind of epoxy resin or maybe araldite?

Jazzyvee
flpete1uw
Advanced Member
Username: flpete1uw

Post Number: 229
Registered: 11-2011
Posted on Thursday, January 02, 2014 - 4:38 am:   Edit Post

Peter, That would be the long term best case scenario.
Jazzy, The problem is the warp age sets the pickups to high in the Bass even with the lower screws removed. Not so much a leveling issue.
A good idea though for repair work.
~Pete
jzstephan
Advanced Member
Username: jzstephan

Post Number: 221
Registered: 1-2012
Posted on Thursday, January 02, 2014 - 7:08 am:   Edit Post

Years of overtightened adjusting screws is the genesis of this problem. Everyone needs to heed this warning. They don't need to be tightened with an impact driver!

Does anyone have any experience with heating these epoxy castings? I bet a little heat would soften them up enough to straighten them in a jig with a block on each end so that the pressure is even across each ear, leaving them in for a couple of days to do some good. Maybe 150 degrees in the oven for 10 minutes to start, and then increase the temp as courage prevails over caution.
mica
Moderator
Username: mica

Post Number: 8083
Registered: 6-2000
Posted on Thursday, January 02, 2014 - 6:55 pm:   Edit Post

There's nothing in mounting flange area except polyurethane, so you can chop it off and it won't hurt the electrics. There isn't any reason you can't sand down the mounting and get them in the cavities lower. More drastic would be making the routings for the pickups deeper (but do mind you don't punch through the back!).

Sorry John, but the material isn't thermoplastic.

You can buy sets of pickups, and even if you don't replace the humcanceller at the same time (you really should) you should at least buy the correct matched one and keep it safe for when you do have a chance to crack the old one out. Email me if you want any other purchasing details.
flpete1uw
Advanced Member
Username: flpete1uw

Post Number: 230
Registered: 11-2011
Posted on Friday, January 03, 2014 - 3:39 am:   Edit Post

Thank you Mica,
An E-Mail will be sent.
Peace
~Pete
flpete1uw
Advanced Member
Username: flpete1uw

Post Number: 232
Registered: 11-2011
Posted on Saturday, January 04, 2014 - 9:01 am:   Edit Post

David,
You mentioned that the pickups shown are an “extra set of pickups”, I’m curious did you replace them with a new/used set?
~Pete
gtrguy
Senior Member
Username: gtrguy

Post Number: 669
Registered: 9-2004
Posted on Saturday, January 04, 2014 - 11:27 am:   Edit Post

No, I have a project series bass that I have been fooling around with for a couple years and I have been collecting parts for it since i bought it. I have two sets of pickups and will see which ones work best with the existing hum-canceling pup in the bass and then sell the other set. However, I don't know when I will get around to doing it!

http://alembic.com/club/messages/411/60995.html?1353883829
flpete1uw
Advanced Member
Username: flpete1uw

Post Number: 272
Registered: 11-2011
Posted on Tuesday, March 04, 2014 - 8:50 am:   Edit Post

As a Follow-up,
I took the plunge in shaving down the warp age in the pickups so now they rest flat. It was a bit un nerving at first but heck what did I have to lose ;) Bottom line is that by doing so corrected most of if not all of the sound issues I was having and gave me more string clearance. Hind sight always being 20 /20, I should have done this a year ago.

Note: Series Pickups have a funky smell when being grinded and abused.:-) ļ
~Pete
musashi
Advanced Member
Username: musashi

Post Number: 205
Registered: 5-2004
Posted on Wednesday, March 05, 2014 - 12:03 am:   Edit Post

As the kids used to say, "Right on," Pete.

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