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paulman
Advanced Member
Username: paulman

Post Number: 301
Registered: 2-2005
Posted on Friday, August 22, 2008 - 7:31 am:   Edit Post

Good morning fellow Alembicster's :-)

I have had my Further for a couple of years now, and have recently noticed that the volume control on the guitar is not very expressive.

For example: if the volume control on the Further is turned down slowly while playing, the volume output does not reduce until the control is almost at the end of it's counter-clockwise travel. The last few degrees of turn are the only position the volume control has any effect. This response (or lack thereof) is the same with the effect loop engaged or disengaged. The Further is running directly into the amp with nothing in the chain between them.

Is there a way to make it more expressive over a greater range? I have tried the same experiment with my Skylark, and with a PRS SE as a control and both of those guitars have an even response as the volume control is turned down on the guitar.

Let me know of any ideas. I searched the forum and couldn't find anything on this particular issue. Thanks a ton and have a Grate and Ful day.

Rog
grateful
Advanced Member
Username: grateful

Post Number: 284
Registered: 12-2004
Posted on Friday, August 22, 2008 - 7:54 am:   Edit Post

Hi Rog,

The volume pot is basically a variable resistor so there is something wrong if it's behaving like that. (My Further's volume pot behaves impeccably.)

Is the pot itself possibly turning? If not, I think you need a new one.

Mark
davehouck
Moderator
Username: davehouck

Post Number: 6940
Registered: 5-2002
Posted on Friday, August 22, 2008 - 8:47 am:   Edit Post

How does the output compare to the Skylark?
paulman
Advanced Member
Username: paulman

Post Number: 302
Registered: 2-2005
Posted on Friday, August 22, 2008 - 9:40 am:   Edit Post

Woah...speedy responses guys. Thanks!

The volume control full output is the same on both Further and Skylark, Dave. And conversely (humor?) the output from the volume control all the way down also is the same on both guitars.

Rog
mica
Moderator
Username: mica

Post Number: 5467
Registered: 6-2000
Posted on Friday, August 22, 2008 - 9:46 am:   Edit Post

That does sound like a problem with the volume pot. Take a peek inside and tell me if you can read a part number 475-XXX on the volume pot. Tell me what you find on the XXX.
paulman
Advanced Member
Username: paulman

Post Number: 303
Registered: 2-2005
Posted on Friday, August 22, 2008 - 11:39 am:   Edit Post

A reply from the head Honcha...TY!

Mica, the part reads 475-020. Good to hear from you.

Roger
dfung60
Advanced Member
Username: dfung60

Post Number: 356
Registered: 5-2002
Posted on Friday, August 22, 2008 - 11:40 pm:   Edit Post

Mica will tell you whether that's the right part number or not, but the description of your problem makes me think that your volume pot is linear taper instead of audio taper. It would not be unheard of for a pot to be mismarked.

The perception of volume is not numerically linear. Doubling the resistance turns out to cause only a small change in volume. To create a perceptual change to 1/2 volume, you need to increase the resistance by a factor of 10. This is the difference between linear and audio taper pots. A linear taper pot linearly scales from no resistance to it's maximum. An audio taper pot is set up so that turning the knob to halfway gives you the resistance you need to make the instrument sound half as loud.

David Fung
paulman
Advanced Member
Username: paulman

Post Number: 305
Registered: 2-2005
Posted on Sunday, August 24, 2008 - 8:25 am:   Edit Post

Thanks for that Dave. Thats exactly what I thought was happening, but hadn't cracked the case to see that the pot is Alembic specific. Now I realize it cannot be replaced with just any old pot off the shelf, which is ok 'cos I didn't pay for any ole off the shelf guitar anyway. The control is still usable, just not as expressive as I'd like.

But, I am totally sure we'll get it working correctly. It's amazing to me that it would actually take me this long to realize it was a problem, as I remember it being that way back when I was testing it at the "store" (Ed Roman's), same volume pot action with the other Further that was there. So natch I just assumed...

Thanks again for da help. Just had a great gig and again, they always comment on the stellar sounding guitar hoorah!
paulman
Advanced Member
Username: paulman

Post Number: 309
Registered: 2-2005
Posted on Tuesday, August 26, 2008 - 7:01 pm:   Edit Post

Hiya. Just checking to see if there's any further thoughts on the volume pot-a-rino.

Thanks a ton.
mica
Moderator
Username: mica

Post Number: 5478
Registered: 6-2000
Posted on Tuesday, August 26, 2008 - 7:33 pm:   Edit Post

The 475-020 is a custom made audio taper pot. As David suggested, your observation is of a linear taper pot. Check to make sure the center terminal of the pot isn't shorted out. That could cause a similar result.

You could send me your electronics, and I can have them tested and repaired. It beats sending in the whole guitar, but even removing and then reinstalling the electronics is not a small amount of work. Keep an afternoon clear and take your time!
paulman
Advanced Member
Username: paulman

Post Number: 310
Registered: 2-2005
Posted on Wednesday, August 27, 2008 - 12:17 pm:   Edit Post

Okey dokey, did some testing after I used my new chisle to get the pot out for testing. BTW how do I glue the wood back in?

Seriously...here is what I found.

The following is referencing the position of looking down on the pot from the top of the control, with pin positions 1 2 3 going from left to right with the pins facing in (or towards the belly). Used an analog multitester for basic troubleshooting. And the control was not isolated from the rest of the electronics during testing, I could not see an easy way to take it out of the circuit.

Turned fully counter-clockwise
1+2=OPEN
1+3=10k ohm
2+3=10k ohm

Turned fully clockwise
1+2=10k ohm
1+3=10k ohm
2+3=OPEN

Please let me know if that pattern is consistent with a properly working Alembic 475-020 Custom Designed Audio Taper control. (sounds official :-) )

Thanks a ton thus far, very interesting!
mica
Moderator
Username: mica

Post Number: 5488
Registered: 6-2000
Posted on Wednesday, August 27, 2008 - 12:50 pm:   Edit Post

So official! Do exactly the same thing, but with the volume control at half rotation to find out interesting things. If it's linear taper, it will be 5K between 1-2 and 2-3. 1-3 should always be 10k. If it's audio taper, 1-2 should be 1-2K and 2-3 should be 8-9K.

When you say "OPEN" do you mean "close to zero Ohms?"
paulman
Advanced Member
Username: paulman

Post Number: 311
Registered: 2-2005
Posted on Wednesday, August 27, 2008 - 1:25 pm:   Edit Post

Ok Mica...the pot measurements at 50% read 1.5k between 1 & 2 and 9k between 2 & 3 so it's an Audio Taper pot. Yay.

Yes, I did mean "close to zero ohms". To be laughingly redundant I should have put 0k ohms :-)

Would you have another suggestion that I could try before (as #5 would put it) "disassemble life form?".

Thanks for the knowledge, that was kinda fun in a way.
paulman
Advanced Member
Username: paulman

Post Number: 312
Registered: 2-2005
Posted on Tuesday, September 02, 2008 - 9:31 am:   Edit Post

Bumpity-bump. Just wondering if there's any other suggestions before I start to dismantle my baby. Thanks and hope everyone had a nice labor day, 'twas gorgeous in Chicago!
paulman
Advanced Member
Username: paulman

Post Number: 314
Registered: 2-2005
Posted on Thursday, September 04, 2008 - 3:10 pm:   Edit Post

Hi, just checking to see if there are any last items I can check into before dismantling the electronics.

I will have some free time this weekend, and would like to perform this operation only as a last resort.

Thanks a ton for all the help so far Mica! Luckily I have a "spare" Alembic so I won't be out of the game if/when the Further is down for service. Yay
mica
Moderator
Username: mica

Post Number: 5506
Registered: 6-2000
Posted on Friday, September 05, 2008 - 5:55 pm:   Edit Post

I'm afraid that the only thing left to do is to send the guts to me. You can leave the filters and pickups installed in the guitar, saving a little trouble. Send everthing else to me and we'll figure out the mystery. I don't think we'll need it for more than a few days.
paulman
Advanced Member
Username: paulman

Post Number: 315
Registered: 2-2005
Posted on Friday, September 05, 2008 - 6:39 pm:   Edit Post

Sweet, thanks a ton. As they say...Knife goes in and guts come out. That's what Osaka Fish Concern is all about.

And no need to be afraid :-) They'll be in the mail soon. Thanks again!
paulman
Advanced Member
Username: paulman

Post Number: 316
Registered: 2-2005
Posted on Tuesday, September 09, 2008 - 11:34 am:   Edit Post

Ok, guts were in...



Now guts are out...


Here is the comparison...


And here is an almost naked control surface Further...



Wiring harness is on it's way. It was super easy to get out...repairable and fixable is how Ron made it and I appreciate that! One question,
all the plugs inside have #147 marked on them. Is that becuase this is Further wiring harness #147?

Thanks a ton so far to Mica and Alembic! Breaking out the Skylark for rehearsal tonight :-)
paulman
Advanced Member
Username: paulman

Post Number: 324
Registered: 2-2005
Posted on Tuesday, September 23, 2008 - 4:10 pm:   Edit Post

Hi all. Mica, are there any "Further" updates? Left a couple messages and sent an e-mail. Let me know when you can, and thanks much :-)
paulman
Advanced Member
Username: paulman

Post Number: 325
Registered: 2-2005
Posted on Monday, October 13, 2008 - 7:15 am:   Edit Post

Happy Columbus Day!

I received the repaired harness on Friday, and was suprised to find that there were new filters sent back with it. So of course all the new guts went and and the old filters came out! (Mica...would you like the old filters back?)

In my haste to get the harness in I forgot to take before pics, but here is an after.

Here is the harness installed, notice the new wire colors. The new wires seemed to be more substantial in than the originals.
Inside

Since all the switches were out, I oriented them a little differently. Previous to disassebly they were oriented following the curve of the body shape, and in the heat of performance I'd slip my hand down and find it difficult to tell which switch I was flipping.

When I re installed them, I reoriented them so they are parallel right angles with each other and switch straight up and down. See pics..



So after all that I didn't have time to test it, and ran off to rehearsal on Sunday. Needless to say, the scream of Further was heard prominently throughout the land! The new harness works perfectly, and my volume control is extremely useable now. This is a testament to the superior design of the harness. Not that I didn't wish to test it before rehearsal, more that I was confident that everything would work great. There was an ease of reassembly due to the plug-in nature of the components; everything is pre-placed and wired so all pots and switches just slip in their holes!

More happened than the Volume control too. Previous to the gut-come-out project when more than one pickup was on, the output gain would increase. I always thought this was a normal characteristic, but I got a call from Mica letting me know there is another option. The gain increase was indeed by design (she said Ron thought it would be cool) and indeed it did add an item of controlthat worked well. However after the upgrade using more than two pickups would NOT increase the gain, and make everything more stable (unless I purposly set the pickups hotter than one another). After a lot of discussion with her (thanks Mica) I decided to get the upgrade. I do use gain sensitive equipment.

So now with the gain output at a normalized level, and the volume control working perfectly (I cannot stress how much I love it) I feel all in control. Woo-hoo!

The Alembic "Further" refined my guitar into it's pure essence, and I say THANK YOU for that! They supported this issue free of charge, I only had to pay shipping to the factory. Best $5k I ever spent (on the guitar that is :-) )

Rock on!

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