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  #1  
Old 04-29-2017, 10:34 AM
Steel Steel is offline
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Default Takamine G260 Pickup problem

I am a relative beginner, having started learning to play a guitar in my youth, but never really making much progress. It will take a while to get back into the swing of things, but since circumstances have led me to an early retirement, I have decided to spend some time playing guitar again. With this in mind I have been searching for a suitable low budget guitar but something a little better than the usual cheap student offerings.

I chanced upon a Takemine G260 with TP4T pre-amp and research suggested that, although aimed at beginner level and Chinese rather than the better Japanese made models, this was still a quality guitar, suitable for a begginer, and costing 230GPB (or $300 in the states). Yet, here it was being offered for 70GBP but with a note to say that the pre-amp and tuner were not working. Cosmetically it was in very good condition although some use was evident. The strings looked practically new. Research and electronics experience suggested that the issue more likely lay with either the jack socket or the pickup. The statement that the tuner was faulty made the purchase decision that much more difficult, but on the other hand if the problem was in the pickup, then might not that affect tuning as well? Even if it could only be used acoustically, it still seemed to represent a worthwhile purchase, so after some consideration, the purchase was made.

Having got it home and put a fresh battery in, I found that two alternating red chevrons were displayed. At least the pre-amp was alive! I could only tune high 'E' though. The other strings would not tune and had to be tuned manually. Initially a quick test suggested that the was no output at the jack, but it turned out that considerably more volume was required. At this point most strings could be heard at only a moderate level, but the the high 'E' string was very much louder. In addition there seemed to be a buzz in the bridge area, particularly when the low E string was plucked. At least this confirmed that the pre-amp was actually working!

To rule it out, I initially checked the jack socket and confirmed that switch was fine. I then proceeded to have a look at the pickup. Having removed all strings and re-seated all connectors on the back of the pre-amp I carefully prised out the saddle to reveal the copper strip underneath, with a blob of solder retaining it at one end. It looks like this one here:

http://www.ebay.co.uk/itm/Takamine-G...-/321940048826

The difference is that the protrusions underneath on this one seem much shorter, so I'm wondering if it has been filed down? Has someone tried to mod it, messed it up and sold it on perhaps? I can probably test the pre-amp to make sure that there is no frequency drop-off issue, but I now suspect that the issue is mechanical.

I have now re-assembled everything and it works the same as before, but I would like to understand how this pickup works, particularly how the sound is transmitted from string via the saddle to the pickup. Is there a diagram anywhere? I tried to find one but to no avail.

With regards to the saddle, can it be purchased separately or does one have to purchase the entire saddle and pickup assembly? Can an alternative pickup or saddle be used? If necessary, can the pickup assembly be removed from the bridge topside, or does the bridge have to be removed as well? (I will not attempt the latter - just want to determine if the pickup can be replaced).

I still have a long way to go before it will be worthwhile using amplification, but I would like to get the guitar amplification back into proper working order. Any insights would be appreciated.

Last edited by Steel; 04-29-2017 at 11:26 AM.
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  #2  
Old 04-29-2017, 11:28 AM
karlitofingers karlitofingers is offline
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Default Takamine G260 Pickup problem

Your very last question is a little confusing but here's what I would recommend. If you can buy a like for like pickup element (the saddle bit) then that is your first step, I'm not aware of the saddle and pickup being available separate). Try it, if you still have problems then you need to decided whether to spend more money on the preamp. If not, due to the connector the pickup element uses, you could get a standard pickup element (braided metal type) and a new saddle BUT, I feel a new hole would need to be made for the pickup to pass through to ensure it runs the full length of the saddle slot because if you use the existing hole you'd be missing a bit at the very end of the slot. If the guitar (after a proper setup and assessment) appears to be a very nice sounding guitar I would hold off fixing the old pickup and fit a new system such as an LRBaggs or K&K. You could then put your money into a pickup you know will work.


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  #3  
Old 04-30-2017, 07:08 AM
Steel Steel is offline
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Thank you for your recommendations. I suppose what I am asking is whether the pickup can be removed from the slot without damaging the bridge? The entire pickup and saddle assembly appear to sit in a groove in the bridge and the whole assembly is on top of the soundboard rather than being fixed underneath.

Since this forum does not seem to allow photo uploads I have hosted these externally and linked them.

The saddle:


The bridge and pickup in the groove:


Apart from the obvious bit on the far left, has this saddle been filed down? Close examination with a magnifying glass of the underside shows what looks like some slight sign of abrasion, although, if so, then it appears to have been done with something very fine so that it is barely noticeable. However the bottom of this saddle certainly looks very different to the one in the eBay photo. In particular, the ends are level with the the remainder of the underside rather than being slightly longer so as to raise the assembly in a bridge-like fashion off the pickup by a mm or two.

Also, what type of pickup this is - piezzo, electromagnetic or some type of hybrid? It would seem that the metal strip is supposed to 'float' above the pads (as it appears to do on the one in the eBay picture) but this one curves up and would likely be touching the pads once the saddle is placed on top.In fact, I would guess that the saddle it compressing the strip against the pads for most part and this is causing the loss of volume for most of the strings.

Please could you also tell me what a 'braided metal type' pickup is? Sorry, I am not familiar with that term. I only found references to braided wire on Gooooooooooogle.

Last edited by Steel; 04-30-2017 at 07:56 AM.
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  #4  
Old 04-30-2017, 08:10 AM
karlitofingers karlitofingers is offline
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http://www.bluestarmusic.com/assets/...20170226103716

See above for the pickup I was talking about.

Your saddle could have been filed yes.

It should be possible to remove all parts of the saddle form the bridge yes, are you saying it's fixed down into the slot???

I wouldn't be concerned about the metal strip, what I would be checking is if the bottom of the saddle is flat and that each part of it is sitting on top of the strip equally, if not some strings won't be picked up properly.
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  #5  
Old 04-30-2017, 10:16 AM
Steel Steel is offline
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Quote:
Originally Posted by karlitofingers View Post
http://www.bluestarmusic.com/assets/...20170226103716

See above for the pickup I was talking about.
Thanks. I haven't seen one like that before. I presume its some form of mic?

Quote:
Originally Posted by karlitofingers View Post
Your saddle could have been filed yes.

It should be possible to remove all parts of the saddle form the bridge yes, are you saying it's fixed down into the slot???

I wouldn't be concerned about the metal strip, what I would be checking is if the bottom of the saddle is flat and that each part of it is sitting on top of the strip equally, if not some strings won't be picked up properly.
I think my experiment below now proves that the saddle HAS been filed and whoever did it, although managing to keep it very flat, did it incorrectly by filing the whole underside to the same level. I just needed confirmation that it was safe to try and lift the pickup out, which I have now done and it actually came out quite easily. This now allowed me to see properly how the two parts sit together. Looking at the eBay pictures of the Takamine G-series pickup, it would seem evident that the saddle is not supposed does not sit flush with the metal side of the pickup as it did with this one. Even with the saddle pushed in, the images show a clear one or two millimeter gap between saddle groove and metal rim.

As an experiment I came up with an idea to raise the saddle a little. There is just about 2-3mm at each end of the pickup where I think the ends of the saddle make contact with the bottom of the pickup, keeping the length in between in a bridge-like fashion above the pickup. Since the width of the pickup is just about the width of a matchstick, I carefully cut two 3mm lengths of matchstick and pressed them into the base on the ends of the pickup being careful not to damage anything and ensuring that the metal strip remained free. I then replaced the saddle on top so that it now sat on the matchstick pieces, but still within the pickup walls, and finally put the assembly back into the groove within the bridge. This had the effect of raising the saddle by about 2mm off the pickup. I re-strung the guitar and plugged the amp in to find that it now works rather nicely on all strings. It is by no means an ideal fix, but enough to prove what the problem was. Evidently the saddle had been modified and too little clearance left for the strip to vibrate properly.

Long term it will probably need a new pickup, but I found that it is possible to buy acoustic guitar saddle material on eBay so it might yet be possible to fashion a replacement.

I'm still having difficulty working out the tuner as all I get are the two flashing chevrons, but that's not a major issue as I can use a separate tuner and my ears!

Thanks for your replies as they have been helpful.

Last edited by Steel; 04-30-2017 at 10:29 AM.
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  #6  
Old 04-30-2017, 11:42 AM
karlitofingers karlitofingers is offline
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No not a mic, Piezo pickup, it's the same material your cable is made from before it goes into the saddle section, look at the one at the ebay link you pasted earlier and compare.

Good you got it working better!


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  #7  
Old 04-30-2017, 11:59 AM
dannyg1 dannyg1 is offline
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(This is probably not your pickup as it is mainly in the higher end Takamines. See the video I posted in the post below this one first) You may have a full paleothetic pickup system in your guitar.if so:

https://m.youtube.com/watch?v=5Z0fz0_fO_E

Last edited by dannyg1; 04-30-2017 at 12:57 PM.
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Old 04-30-2017, 12:06 PM
dannyg1 dannyg1 is offline
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Here's a more likely match:

https://m.youtube.com/#/watch?v=TDyWdhz0OFw
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Old 04-30-2017, 02:37 PM
Steel Steel is offline
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dannyg, you are quite correct. Mine is not a paleothetic pickup like on the more expensive Takemines. I believe it is a piezzo pickup, as it is identical with the one shown in the second video that you linked, although I had to go to a slightly different URL:

https://www.youtube.com/watch?v=TDyWdhz0OFw

In fact when he takes it apart, it becomes very clear that the bottom of the saddle on mine, being completely flat all the way across, is the wrong shape. I did incidentally check for bad wiring like in the video but mine did not have that particular problem.

Thanks for pointing out these videos.

karlito, that pickup looks just like a piece of cable with a jack plug on the end! It is presumably so miniature that it fits into that braided sleeve. I now understand what you mean about needing another hole, but I don't think it would be a problem because the hole seems to start maybe 5mm from the tip of the slot, but does seem to run all the way up to the end, so it would probably fit quite nicely. Something to think about later. It does state on the listing that:

Quote:
This pickup requires a matching LR Baggs preamp to operate correctly, it is not suitable as a standalone pickup and will not work with other preamps.
Is this just about proper impedance matching, or have they done something else to prevent compatibility?

Last edited by Steel; 04-30-2017 at 02:43 PM.
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Old 04-30-2017, 02:48 PM
karlitofingers karlitofingers is offline
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Quote:
Originally Posted by Steel View Post
dannyg, you are quite correct. Mine is not a paleothetic pickup like on the more expensive Takemines. I believe it is a piezzo pickup, as it is identical with the one shown in the second video that you linked, although I had to go to a slightly different URL:

https://www.youtube.com/watch?v=TDyWdhz0OFw

In fact when he takes it apart, it becomes very clear that the bottom of the saddle on mine, being completely flat all the way across, is the wrong shape. I did incidentally check for bad wiring like in the video but mine did not have that particular problem.

Thanks for pointing out these videos.

karlito, that pickup looks just like a piece of cable with a jack plug on the end! It is presumably so miniature that it fits into that braided sleeve. I now understand what you mean about needing another hole, but I don't think it would be a problem because the hole seems to start maybe 5mm from the tip of the slot, but does seem to run all the way up to the end, so it would probably fit quite nicely. Something to think about later. It does state on the listing that:



Is this just about proper impedance matching, or have they done something else to prevent compatibility?


Possibly impedance but most likely them covering their backs. Was just using that one as an example really.


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  #11  
Old 04-30-2017, 02:48 PM
dannyg1 dannyg1 is offline
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If it's a standard Baggs pickup, it's the LB6. If it's the LB6 it has an ultra high impedance and Baggs makes an end pin pre for it now. Given what you'd written earlier and what I've seen in the video, it should be pretty straightforward to verify that the pre is working.
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Old 05-02-2017, 09:58 AM
Steel Steel is offline
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Well the good news is that I have been able to obtain a replacement saddle via the Takemine UK distributor, which is Korg Uk. It should arrive by the end of the week. I should then be able to replace my temporary kludge with a properly fitting saddle and hopefully the problem will then be resolved.
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  #13  
Old 05-08-2017, 02:57 PM
Steel Steel is offline
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The replacement saddle arrived today. After fitting it, things were sounding a lot better. The sound though the amp now has a much cleaner and brighter quality to it, the volume is greatly increased and it seems much easier to pick out the subtle changes to the tonal quality when the sliders on the pre-amp are adjusted. My temporary fix went some way towards fixing the problem, enough to prove that the pre-amp was working OK and giving me hope that the pickup might still be serviceable, but the new saddle seems to have made all the difference and has solved the remaining problems. The pickup now seems to work very well and the built-in tuner also functions as expected (although I haven't yet tested the 'arbitrary reference frequency' mode), allowing me to tune with ease and with reasonably accurate results. Overall I am really pleased with it and certainly looking forward to getting some enjoyment out of playing it!

Thanks for all the helpful comments.
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