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Building a Wal....ish


funkle

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On 21/12/2021 at 10:00, Andyjr1515 said:

 

 

 

Done that now (twice) and even more fascinated!  :)

 

 

 

That was me :)

 

It was a neck repair/mod and rebody for @Fishman 's Pro 1e neck/plate and pickup.  The thread is here:

 https://www.basschat.co.uk/topic/443139-finished-a-very-special-save

 

 

It's a bit of a tortuous thread (all of mine are ;) ) so you will be relieved to know that the bit where I take the fretboard off is on the first page  :D

 

And yes - all components (including the player's finger-end hardness) make a contribution to the sound, but the lion's share on a Wal is, in my own experience, influenced by the pickup(s) and EQ.

 

 

 

I'm loving this thread  :)

 

 

Wow @Andyjr1515 that thread was one heck of a read. Amazing work.

 

I know who someone else who can help me make the multi-laminate neck now if/when I get to that stage! 

 

Edited by funkle
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1 hour ago, Rich said:

 

Sorry I'm a bit late to the party...my Pro 2E measures as follows:

From centre of the 12th fret to the centre of the front pickup, 295/296mm

For the same measurement for the rear pickup, 379mm. 

 

You legend! I'll update the original 'measurements' post with this info. 

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Managed to get hold of a secondhand Cort GB74JJ to use as a second test subject. Cort secondhand prices are pretty affordable. 
 

I’m minded to wait and see how things go with the first test bass before doing too much with a second. If it turns out that the Cort is not necessary, then I’ll simply sell it on here. 

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Posted (edited)

Does anyone have a Mark 2 and/or a Mark 3 they could measure pickup spacing on?

 

I'm doing the calculations from the Talkbass post I linked to earlier to try and work out all the pickup spacings, but I'm not convinced they are correct from comparing photos of the Mark 1, Mark 2, and Mark 3 side by side. Best way to know is to have someone measure....as it stands I'll have to use either the Pro or the Mark 1 spacing.

 

To clarify, here's how everything looks side by side between the Mark 1/2/3 (from left to right):

 

1986710732_WalBassModelsPickupSpacing.jpg.35ae93712c37fd4d25b3b8c9f942f83c.jpg

The Mark 2/3 have the bridge pickup in roughly the same spot I think, with the Mark 1 having it furthest back. The Mark 2 appears to have the front pickup moved further towards the bridge than the Mark 1, and the Mark 3 moves the front pickup closer to the neck than the Mark 1. 

 

Edited by funkle
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Hi Yes I have a mk 1 and a mk 2 (though the mk 2 has 5 strings and hence different pickups to the mk 1). On MY mk2, the bridge pickup is closer to the bridge than on the mk1!  Anyway, from the centre of the D-string bridge saddle (which is set to give a perfect octave at fret 12) to the pickup pole piece heads:

 

Bridge pickup lowest:   mk1:    45mm .  mk2:  40mm

Bridge pickup highest  mk1:    71mm.   mk2:  65mm

 

Neck pickup lowest:  mk1:     130mm.  mk2:  125mm

Neck pickup highest: mk1:    156mm.  mk2:  150mm

 

Judging by various mis-alignments on both my Wals, I have a theory that Pete Stevens did a lot of stuff by eye - so every bass could be a bit different!  Paul Herman, I think, is micron accurate in his builds.

 

Concerning much earlier queries; I can confirm that both the mk1 (1986) and mk2 (1991) have the same "new" pickup wiring.  Ie there is one wire per coil pair arriving in the control cavity.  Those "coil pairs" are then summed together for each pickup (with a bit of tone shaping I think, judging by the R and C on the input to the summation op amp) before the signal is send to the filter circuit.  I can't read those R & C values and not taking the amps out just to find out .. not today anyway.

 

Finally "switches to allow series/parallel operation (and perhaps single rows of coils, wait and see), and an ACG EQ-01 for the preamp." 

 

a)  Yes, I sometimes wish my Wals had those switches.  Single coil would sound better for harmonics and slap I think (though can't confirm) but surely at the expense of hum.  Series parallel?  I take it you mean series or parallel connection of the "coil pairs" rather than of the individual poles.  The Wal electronics "sum" all the pickup coils together via a buffer circuit, so effectively everything is in series and the coils don't load eachother; you might get a different sound if the coils did load eachother a bit (ie parallel wired before any bufferring / summation), but I can't see that would be a good thing.  Different from a Fender where the pickups load eachother and the output is some sort of "average" of both pickups rather than a sum.  Presumably you're not planning that level of switchability!

 

b) I have an ACG-eq-01 in a bitsa jazz bass I had made years back (and adapted endlessly).  It was supposed to have "elements" of wal-ness about it (it doesn't really).  There is a big difference between the Wal and ACG electronics - apart from the ACG being so adjustable it's quite hard to find and replicate the setting you want (hence the new DFM? version).  The main thing though is that the Wal electronics soft clip (ie distort a bit) when pushed hard, this is a core Wal tone for me and IMHO key to the sound of the fretless basses.  The ACG does not distort at all, until it clips (nastily) .. it is totally linear, so just doesn't do the Wal soft distortion thing.  I guess (and it's been discussed at length) that this is due to Wal using ancient lossy op amps from the 70s instead of nice new FET based ones!!

 

Good luck.

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Posted (edited)

 

@NickA thanks so much. You know, with everyone chipping in so much, I really feel like this is almost a community project. I've been spoiled with offers of help and the preamps etc, it's just great.

 

2 hours ago, NickA said:

Hi Yes I have a mk 1 and a mk 2 (though the mk 2 has 5 strings and hence different pickups to the mk 1). On MY mk2, the bridge pickup is closer to the bridge than on the mk1!  Anyway, from the centre of the D-string bridge saddle (which is set to give a perfect octave at fret 12) to the pickup pole piece heads:

 

Bridge pickup lowest:   mk1:    45mm .  mk2:  40mm

Bridge pickup highest  mk1:    71mm.   mk2:  65mm

 

Neck pickup lowest:  mk1:     130mm.  mk2:  125mm

Neck pickup highest: mk1:    156mm.  mk2:  150mm

 

Judging by various mis-alignments on both my Wals, I have a theory that Pete Stevens did a lot of stuff by eye - so every bass could be a bit different!  Paul Herman, I think, is micron accurate in his builds.

 

 

I now feel a lot better now about pickup spacing, almost relieved to hear it was a bit 'eyeballed'. I was driving over to Chris McIntyre's today, angsting all the way about whether to stick with the Mark 1 pickup spacing or not. As it turns out, the routing on the bass will allow for either Pro or Mark 1 pickup spacing, so I can change it if I want to experiment, but even so, I now feel confident enough to just leave it as it is. Thanks for that.

 

I'll have to work out how your pickup measurements would translate to distance from centre of 12th fret to centre of each pickup, but I think I can do it from what you have generously given. 

 

2 hours ago, NickA said:

Concerning much earlier queries; I can confirm that both the mk1 (1986) and mk2 (1991) have the same "new" pickup wiring.  Ie there is one wire per coil pair arriving in the control cavity.  Those "coil pairs" are then summed together for each pickup (with a bit of tone shaping I think, judging by the R and C on the input to the summation op amp) before the signal is send to the filter circuit.  I can't read those R & C values and not taking the amps out just to find out .. not today anyway.

 

Ah, good to have it confirmed re: Mark 1 wiring. Thank you. 

 

2 hours ago, NickA said:

Finally "switches to allow series/parallel operation (and perhaps single rows of coils, wait and see), and an ACG EQ-01 for the preamp." 

 

a)  Yes, I sometimes wish my Wals had those switches.  Single coil would sound better for harmonics and slap I think (though can't confirm) but surely at the expense of hum.  Series parallel?  I take it you mean series or parallel connection of the "coil pairs" rather than of the individual poles.  The Wal electronics "sum" all the pickup coils together via a buffer circuit, so effectively everything is in series and the coils don't load each other; you might get a different sound if the coils did load each other a bit (ie parallel wired before any bufferring / summation), but I can't see that would be a good thing.  Different from a Fender where the pickups load each other and the output is some sort of "average" of both pickups rather than a sum.  Presumably you're not planning that level of switchability!

 

I realise I should have been clearer in my description of the pickup wiring. 

 

In each row of individual coils, the 4 coils are first wired together in series. The switching will allow the two rows of 4 coils (all in series) to have their outputs then wired together as either series, parallel, or single row (in my case, each front row on its own). You are right, wiring each row of 4 coils together in parallel would not be similar to the originals, and would not work the way we want. 

 

It will effectively be the 'Pro' wiring, with a bit more switchability, with a sort of 'Custom' preamp. Maybe on another project I could get the pickups wound like the 'Custom' series - one pair of coils per string - and then get a Lusithand Double NFP Special to buffer them.   

 

2 hours ago, NickA said:

b) I have an ACG-eq-01 in a bitsa jazz bass I had made years back (and adapted endlessly).  It was supposed to have "elements" of wal-ness about it (it doesn't really).  There is a big difference between the Wal and ACG electronics - apart from the ACG being so adjustable it's quite hard to find and replicate the setting you want (hence the new DFM? version).  The main thing though is that the Wal electronics soft clip (ie distort a bit) when pushed hard, this is a core Wal tone for me and IMHO key to the sound of the fretless basses.  The ACG does not distort at all, until it clips (nastily) .. it is totally linear, so just doesn't do the Wal soft distortion thing.  I guess (and it's been discussed at length) that this is due to Wal using ancient lossy op amps from the 70s instead of nice new FET based ones!!

 

The ACG EQ-01. I think the amount of tweakability worries me. I have probably overdone it on the coil switching as well. I also suspect, like you, that the the newest (and simplest) ACG preamp ditched a lot of the tweakbility because it was too much. 

 

I have a possible fix by using these numbered knobs (https://meisterworks.myshopify.com/en/products/luminlay-knobs-ia?variant=31840127090739) and installing markers like on the Wals.

 

Soft clipping  in the Wal preamp. I can't sort that, but I can introduce distortion afterwards with my amp or pedal, I guess....However, I still come back to one of my original points. If the preamp has the magic, then why does a single pickup passive Wal Pro sound so...'Wal-ish'? The answer must be that a lot of the magic is in the pickup itself. I submit the following to you for your consideration:

 

 

  

Wish I could figure out how to make video links smaller...they kind of occupy the whole page, apologies.

 

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Posted (edited)

I meant to say, I have dropped off the test bed bits off with Chris McIntyre today. He's a gem, very kind to put up with my experimentation. Hopefully he can get it sorted out in the next few weeks.

 

I ended up using the Mark 1 pickup spacing. So between that and the 'Pro' style series wiring, the ACG filter preamp, and avoiding rosewood for the fretboard, it's a real mash-up. 

 

I expect the test bed to be a fairly bright sounding instrument, probably a lot brighter than the usual Wals. We'll see. A lot rests on the pickups now. 

 

Chris and I have talked through next steps if things work out well. Probably a multi-laminate neck with pao ferro fretboard, maybe consider an ash or mahogany body; we'll see. 

 

I am both excited and apprehensive. 

Edited by funkle
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Posted (edited)

A little bit more about the pickups

 

For those who are interested, I tried to find out as much as I could about the Wal pickups.

 

There are a bunch of good links from way back when on the Music Electronics Forum. Some of you may remember David Schwab, who ran SGD Lutherie, a pickup maker in the US who went bust fairly acrimoniously in 2010ish(?). At any rate, one of his projects was analysing a Wal pickup, with a view to reproducing it. He wrote a lot on that particular forum about Wal pickups. Another maker, Marko Ursin (MPU on Talkbass), who has experience making Wal clone pickups, as well as others, chime in at various points. Plus of course the chap who makes the pickups I ordered. 

 

There are quite a few helpful links:

 

https://music-electronics-forum.com/forum/instrumentation/pickup-makers/8142-here-s-an-interesting-pickup

 

https://music-electronics-forum.com/forum/instrumentation/pickup-makers/15856-wal-mk1-pickup-construction

 

https://music-electronics-forum.com/forum/instrumentation/pickup-makers/39281-wal-bass-pickups 

 

So here's what they look like on the inside:

 

WAL_pickup_inside.jpg.a6b73d2bd785ef334c66e1fff69a10b8.jpg

 

Wal_bottom.jpg.35547e827be17529676e1f2c299b3c4e.jpg

 

wal_side.jpg.bc9ac5ad882b25930ea7f992a8ce24a2.jpg

 

One of the users on that forum, Belwar, did some very accurate drawings of these pickups:

 

image_6485.thumb.jpg.f4a85f15cf209aa5c759383a98dd462e.jpg

image_6486.thumb.jpg.60513decc6c63b187632e1118c9f937e.jpg

image_6492.thumb.jpg.9d04a81bdf11cf3f0ccb09841b6ec7dc.jpg

 

image_6504.thumb.jpg.56c0b9b266ee891ce218498896f4bbd3.jpg

 

image_6507.thumb.jpg.32dceb7557ecf15f114caf997d57fc1b.jpg

 

So if anyone else is interested, I'm certain at least Belwar has drawings they could share for accurate production...

 

8 coils, each row of 4 wired in series and then those two rows in series (Pro Series/Old style) or parallel (Custom Series/New way), with 4 ceramic C8 magnets, stuck together to make it look like a pair of two magnets. The adjustable poles pass through the coils, through the circuit board that holds the coils, and then into the steel keeper bars. Coils are 0.752" in diameter, 0.451" tall and have 10,000 rounds of 42AWG wire. Each coil has DC resistance of 2.5k, with each row then being 10k. 

 

Belwar took Gauss readings off of pickups he found as well. I quote:

 

'I measured the gauss readings off the poles of two pickups today. Here they are for posterity (did I even spell that right)?

Mk1 Bridge Pickup

 

South Towards Neck

Top row of poles from bass to treble side 698, 617, 655, 739

Bottom row of poles from bass to treble side 892, 810, 670, 705


Mk3 Neck Pickup

 

South Towards Neck

Top row of poles from bass to treble side 676, 800, 792, 800, 842

Bottom row of poles from bass to treble side 742, 763, 776, 823, 740'

 

Marko Ursin did a great job of showing how to make a multicoil if anyone is interested - http://www.talkbass.com/threads/multicoil-pickup-pictorial.1101377/  or at https://music-electronics-forum.com/forum/instrumentation/pickup-makers/39281-wal-bass-pickups?p=556602#post556602

 

Now, to put it shortly, I think the chap doing the pickups I ordered is doing them very close to the originals. Not exact, but pretty close. 

 

Hope this is all of interest to you all!

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Fascinated by this.  Loved the sound of my Wal to bits, hated everything else about it.  I've yearned for the sound every since I got rid, but the absolutely abhorrent profiteering in the used Wal communities has kept me away for good, and they're still much more than I can afford new anyway.  

 

Certainly agree such a huge part of the sound must be the pickups.  I bought an ACG with regular humbuckers and a filter preamp whilst I still had the Wal in some kind of hope it would emulate it in some way, but no, not even remotely Wal like.  ACG have since released their own MC pickups too and have updated the preamp, but from YT videos it doesn't seem they get that close either.

 

That sound clip of the pups you've bought sounds brilliant, and I can only imagine a filter pre would help bring out more.  Intrigued!

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23 minutes ago, matbard said:

ACG with MC and new East preamp (DFM) will give you that sound for a fraction of the price.

And way more.

  
Phenomenal! Do you happen to have any videos or audio? I haven’t really seen any of his latest pickups/pre on YouTube.

 

I did email Alan and feel things out a little. However, when I looked into possibly ordering from Alan, I ran into two issues.
 

The first is that the top of the line pickups and preamp he offers takes me into £3k+ territory for one of his builds. A bit much for what I had envisioned. This experiment is not cheap, but it’s cheap-er…
 

The second, is that I could not get on aesthetically with his headstocks. And it seemed too much to ask him to alter his headstock for a build - firstly he’s well within his rights to say no, and secondly it is part of his overall aesthetic/vision for his instruments, and I suspect quite personal. 

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46 minutes ago, Eisen said:

So what?

Fingers matter too 😇

 

 

 

Think they were the videos I saw.  The MCs get things a little closer than before, but it's just such a polite tone, none of that Wal character.

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4 hours ago, matbard said:

ACG with MC and new East preamp (DFM) will give you that sound for a fraction of the price.

And way more.

 

Do you have any sound clips where an ACG sounds like the tones in the OP?

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I was in Paul Herman's workshop, just pre Covid, and saw the trays of tiny wound coils ready to be hand assembled into the pickups.  Electrical jewelry ... some had gold plated pole pieces, which just seems silly to me.   At least eight of those tiny coils in every pickup.  They don't exactly knock those out in a chinese factory.

 

PS:

On 03/01/2022 at 16:19, funkle said:

I submit the following to you for your consideration:

 

I like the sound of the twin pickup pro bass (the lower one) in those clips a lot more than that of the passive pro1 re-issue (the red one).  What is the lower bass?  A pro2 or a pro2e?

 

That clip in the very original post was a guy called Vic Montello; he had a couple of Wals and used to post on the FB page a lot; that black one is a pro2e, but he plays it though a bank of stuff to make it sound as much as possible like Geddy Lee ... not in my view a very typical Wal sound, but he's very into it (along with weird pro Trump american politics ....... ).

Edited by NickA
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1 hour ago, NickA said:

I like the sound of the twin pickup pro bass (the lower one) in those clips a lot more than that of the passive pro1 re-issue (the red one).  What is the lower bass?  A pro2 or a pro2e?

 

That clip in the very original post was a guy called Vic Montello; he had a couple of Wals and used to post on the FB page a lot; that black one is a pro2e, but he plays it though a bank of stuff to make it sound as much as possible like Geddy Lee ... not in my view a very typical Wal sound, but he's very into it (along with weird pro Trump american politics ....... ).


The lower bass was a Pro 2 - passive. 
 

The video I posted of Vic was apparently him just through an EBS Comp, and his amp. Nowt else - or so he said in the comments for his video.

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I asked Vic :

 

Sounds totally different from my MK2.   Some heavy eq and/or effects in there .. or is that what it sounds like in the raw?  Bright strings part of it I guess.

 

he told me:

 

"SWR head, EBS Multi Comp and Ged 2112. Daddario EXL170s."

 

The "Wal" sound is very setup dependent and that GED 2112 changes the sound quite a bit.  But the pro2 sounds good. Certainly not "just" the electronics.

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2 hours ago, NickA said:

I asked Vic :

 

Sounds totally different from my MK2.   Some heavy eq and/or effects in there .. or is that what it sounds like in the raw?  Bright strings part of it I guess.

 

he told me:

 

"SWR head, EBS Multi Comp and Ged 2112. Daddario EXL170s."

 

The "Wal" sound is very setup dependent and that GED 2112 changes the sound quite a bit.  But the pro2 sounds good. Certainly not "just" the electronics.

It could be more than one thing. 

Amps: If he's using an SWR SM400, it's coloured with a mid scoop.  Great for bright, aggressive basses, especially graphite necked instruments like Modulus Quantum or Flea.  But not ideal for anything with a mid emphasis (it flattens the growl) or a mid scoop (can make the mids even more difficult to hear on stage).  I would have suggested he go through a Class D head like a GB Shuttle or EA iAmp, or an Eden WT500/600 or even a GK RB700. 

Strings: D'Addario EXL170's are nickel, which are a load better than their stainless steel equivalents. While they're durable, I've also found them stiff sounding but for rock that might not be a bad thing.  Again, stiffness removes the mid growl.  He might be better off going with strings that have less tension e.g. Elixirs which can be quite warm and smooth sounding, Warwick Red Label or LaBellas.  

 

The EBS may or may not do much depending on how aggressively he's compressing the signal.  It doesn't sound maxed out in the clip, so he's probably using it to sweeten things up a fraction.

The GED sounds a bit mid scooped to me as well and it introduced a bit too much grind, it gets in the way of things.  But clearly he's going for the Geddy sound which is a bit more aggressive than many Wal players I've heard.

IME the best thing to use for a mid prominent bass like a Wal Mach/Custom, a Smith BSR, a Vigier Passion 5, a Status 2000/Stealth or a Warwick Dolphin is an older Class D head like the Shuttles I use.  They're as close to flat response as it's possible to find on the bass market when controls are zeroed.  GK RB700/1000 amps are worth considering for the boost control which actually drives the mids more into the power amp, lending a soft overdriven snarl to things without losing any definition.

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Loving this topic, really interesting stuff!

 

In regards to the Preamps, I fumbled about with some filter preamps in my last build : 

 

They can be a bit tricky, but while i was doing the research i found that there were some fairly big differences between different manufacturer's filters:

 

 

On 18/01/2021 at 13:26, mhoss32 said:

Okie dokie, lets talk Filters

(if youre only here for the pretty pictures of woodwork, don't worry this part wont be on the test)

The idea for the controls on this bass are as follows; each pickup will have its own preamp, which will have controls somewhat similar to alembic's filter preamps. that means that each pickup will have its own Low pass filter, with adjustable cutoff frequency, and adjustable resonant peak. the layout for each pickups will be like this:

controls2.thumb.png.74c4e05bc31facb4c5c64963a0ead76b.png

This will be achieved with 2 potentiometers, 1 which controls the frequency sweep such as this:

freq3.thumb.JPG.0bddad224ddf190abecd04be17d0dc8f.JPG

as the control is turned, the cutoff frequency decreases and more and more of the treble and Mid frequencies are filtered out, leaving only the low end. you can see from the graph above there is a 12 decibel "peak" at the cutoff point. this is often referred to as the 'Q' or Quality factor, and can also be varied.

The second potentiometer will control the 'Q' factor or resonant peak such as this:

res3.thumb.JPG.ae64ed79ffd5e9641130641e447a3c5e.JPG

These controls should allow for a very wide range of tones, especially with one filter for each pickup. the exact range of both the frequency sweep (from maximum to minimum frequency cutoff) and the range of the resonance control are yet to be decided. once i have a test board made i will try a number of different vlaues to decide which sounds best. it may be that i use different values for the bridge and neck pickups to achieve a greater range of adjustability.

My thinking at the moment is that i will try 3 different frequency ranges:

Low - 250Hz through to High - 3.8kHz (from the research i can find online this is similar to the range sweep of Wal's current electronics)

Low - 300Hz through to High -4.8khz (again, from my research this is similar in range to that of alembic's filters, although it also seems this varies from one set of electronics to another in alembic's case)

Low - 100Hz throught to High -6.8khz (this is a far wider range of a sweep, but may be useful with one filter per pickup as it allows the resonant peak control to boost high treble frequencis on one pickup. this is close but not quite as wide a range as ACG's EQ01 and 02 i believe. i have an ACG EQ02 in one of my Buzzards, and i absolutely love it, but the sensitivity of the frequency sweep control takes some practice to get right)

I want to balance a wide range of tones with the frequency controls not being too sensitive, as its important to have a control setup that allows people to easily recreate sounds accurately without too much effort

For the Resonant peak control, ive decided to go with a potentiometer rather than a switch. again this is based on my own experience with the EQ02, being able to sweep the resonance from low to high i find that at least half of the time i have the control not at either extreme.

from what ive read and from videos ive watched, both ACG and Wal filter preamps have a resonant peak adjustment from 0-10db at the cutoff point. (thats the peak you can see being adjusted in the second graph), and Alembics (take this with a pinch of salt because ive heard a lot of different answers for this from different people) have an adjustable peak up to 15db

again, i think i will test with a number of values, allowing for a peak of 10, 12, 15 or 18Db (18db being the highest boost commonly available on preamps from aguilar, bartolini etc)

and then we come to the "experiment" part of this design. Im confident i can get a compact circuit to achieve all of the above, but i also want to try something different.

as far as i'm aware, all of the aforementioned filters are what is referred to as "2nd order" filters, which have approximately 12db of rolloff per octave (this is the steepness of the rolloff at the filter frequency). it is possible, however to create Higher order filters with a steeper rolloff. a 4th order filter for example would have a rolloff of 24db per octave:

4.-Ideal-Frequency-Response-of-the-Butterworth-Filter.jpg.1eddd7eba9f217cfad0e1fe572b7e922.jpg

In terms of tone, this control would not necessarily be particularly useful if it were applied to both pickups at the same time, but with individual filters per pickup, this would allow the neck pickup to have more of the midrange harmonics filtered out at the bottom end of the frequency sweep, giving a cleaner bass tone, and at the upper end of the frequency sweep, this would allow for the resonant peak to attenuate high treble frequencies whilst filtering out unwanted high frequency noise more effectively.

Thats the theory anyway... it remains to be seen if this works the same way in practice

2and4.thumb.JPG.a937cf3e131866121246900f6f60aee9.JPG

This plot shows the frequency sweep with the filter in both modes, the red traces are in 2nd order mode, and the blue traces are in 4th order mode with the resonance control set to a max peak of 12db.

as i said before, this is an experiment, but im excited to see what this sounds like in practice.

I will cover the preamp in a bit more detail once its been put together and ive decided on component values.

Meanwhile the strips of Cherry are all glued up around the Padauk, and the layers of the wlanut are next :)

IMG_20200821_114620.thumb.jpg.bf5a395fbb5966bbac03e9e175e11bf8.jpg

 

 

 

One other thing that the Wal filters have (aside from the relative simplicity of having a single frequency sweep and a simple hi/lo resonance from the push pull pots) is the "pick attack"

 

That is a real challenge to get right. Ive got a couple of prototypes for a preamp with this feature out there, @Andyjr1515 & @benh were kind enough to give me some good feedback on the design so im still working on some improvements

 

as you said above, multi coils are extremely time intensive to build, hence the expense!

 

Really looking forward to seeing this come together!!

 

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The John East version of the pick attack is simply a hi pass feed forward from the pickups to the volume stage.  However, being Mr East, you can adjust how much of each pickup is fed forward, the hp frequency of the filter and the feed forward gain ! The Wal one is just a simple hp boost I think.

 

My hearing is age compromised enough to prevent me hearing the pick attack on my fretless, but it's clearly doing something (around 5kHz according to my spectrum analyser) and I can hear it on the fretted one.

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17 minutes ago, NickA said:

The Wal one is just a simple hp boost I think.

I looked it up on the Wal site and they say:

Quote

This adds narrow band of high frequencies to the overall tone-setting to provide dynamic, percussive attack.

 

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