Building a Wal....ish

[bloke_zero]

6 hours ago, luthifer said:

Not bad news, just surprising they want to boost way up there. I spent enormous amounts of time playing with a pick and trying different frequencies to get the same kind of meaty pick sound, and settled on ~2k. 6k seems more like a "fret noise" boost to me...

With some studio EQ you add 'sweetness/sparkle' by boosting very high frequencies, 14K plus. Maybe this is on that same sort of basis?

 

The Luistand pre I have I think cuts off at 4K - I can see why you might want to add in some top end just to provide some defintition in that case. Say you cut everything above 2K you could then add some attack, like the click at the start of an electrictronic bass drum.

 

I agree about the fret noise though - especially with my terrible technique!

Edited April 14, 2023 by bloke_zero

[LukeFRC]

3 hours ago, funkle said:

A lot will depend upon the cabinet/crossover design.

I had a early 80's Thumb bass a while back ... the MEC preamp and active SD pickups designed in an era before tweeters/horns in bass cabs were common. 
I ultimately sold it as I was normally DIing straight into the desk and using IEM and there was so much top end it was painful 

[luthifer]

8 hours ago, bloke_zero said:

With some studio EQ you add 'sweetness/sparkle' by boosting very high frequencies, 14K plus. Maybe this is on that same sort of basis?

 

The Luistand pre I have I think cuts off at 4K - I can see why you might want to add in some top end just to provide some defintition in that case. Say you cut everything above 2K you could then add some attack, like the click at the start of an electrictronic bass drum.

 

I agree about the fret noise though - especially with my terrible technique!

This is what my current FT4 treble boost filter is doing. It has a fairly soft knee (Q=0.5 I think) and the boost is settable with a trimmer. I tried going a little lower, but then the sound comes back to pretty much what you get with no LPF and some bass boost, unless you are only using the LPFs set way down low. It also has a pickup selector microswitch, and there's a big difference: The neck pickup (like Wal) gives a clean sparkle, and the bridge gives a much fuller sound. Setting the gain right is also critical or it gets nasty.

 

One thing I might do is switch to a bandpass filter with a fairly sharp peak, to accentuate the pick sound somewhere around 1.8-2.5k, but eliminate the boosted fret noise. It works pretty well with the high filter on my two-band parametric eq, but that's maybe not sharp enough.

[NickA]

My pjb amp "high" EQ knob is at 12kHz. Speaker -3dB at 15kHz.  The only use for that Hi EQ knob is getting extra slap sparkle.

 

 ... must be high bandwidth as I can hear what it does and the next one down ( high mid ) is at only 2.5kHz. 

[crazycloud]

On 11/04/2023 at 04:38, HotelX said:

Also a related question, how is the power consumption on them? Are they all fairly power efficient?

 

Alembics are current hogs, at least in the Series.

On 11/04/2023 at 05:57, NickA said:

Wal and Alembic have filter Q switches ( boosts at the cut frequency).

The S2 have variable Q via pots.

[Kiwi]

48 minutes ago, crazycloud said:

Alembics are current hogs, at least in the Series.

Mine's not noticably thirsty compared to other basses I've owned. 

[crazycloud]

1 hour ago, Kiwi said:

Mine's not noticably thirsty compared to other basses I've owned. 

Mine were, and for good reason; none of the opamps used were low power designs and there were lots of them used. When I was on the Alembic Club, I saw many comments about how Series basses when played on batteries and not the DS5, ate through them very quickly, like 10s of hours, not hundreds.

 

I seldom used mine on anything but an outboard supply, usually my own design as the factory unit was pretty average.

Edited April 20, 2023 by crazycloud

[Kiwi]

1 hour ago, crazycloud said:

Mine were, and for good reason; none of the opamps used were low power designs and there were lots of them used. When I was on the Alembic Club, I saw many comments about how Series basses when played on batteries and not the DS5, ate through them very quickly, like 10s of hours, not hundreds.

 

I seldom used mine on anything but an outboard supply, usually my own design as the factory unit was pretty average.

OK but I have changed the batteries only once in mine after 12 years of ownership.  Not that I play it every week but still...much more than twenty hours in total.

[bornleft]

have you had a chance to test the "reverse engineered" pre-amp?

[funkle]

4 hours ago, bornleft said:

have you had a chance to test the "reverse engineered" pre-amp?

Not yet, unfortunately. 

[bornleft]

Do you know if anyone has generated a .dwg (auto cad) file of the Mark2 layout?

[bornleft]

Also, when I go back and listen the u-tube video of the Turner+Lusithand installed in the Jazzus bod:y https://youtu.be/p7g1cpHSyQk the output is a

long way from the Octave bass recording:  https://www.youtube.com/watch?v=3mCuSYD9Drs

 

Is it not true that the Octave guy is using the Lusithand amp?  If so, then the Turner pickups must be the predominant issue...  

 

Would you not agree that the Octave guy has solved this problem???????

 

 

[funkle]

The Octave chap is using his own design pickups and his own preamp. We have talked.
 

I don’t know if he has solved the problem yet, though he is working hard on it - it’s his niche…

Edited April 28, 2023 by funkle

[bornleft]

who are you referring to?

[bornleft]

Just for the record, Octave man will be selling his p/ups and amps at the end of the summer

and I think it is obvious that he is the only one thus far who has achieved the goal...  If you disagree,

post a link to a sound sample...

[funkle]

@bornleftthe onus of proof isn’t on me. I just don’t think from the clips I have heard that the Octave basses are as close to a Wal as I would hope, yet. We’ll see how it goes over time. I don’t think I’ve heard a clip with his newest preamp though. 
 

And my prior comment was referring to Dario at Octave basses, who I know has been working hard on his Wal pickups and Wal preamp. 

[bornleft]

They may not be as close to what "might" be achieved, but they are much much closer than what Lusithand and Turner sounds like

[funkle]

Fair enough, everyone is entitled to their opinion. All I can say for now is that I await a bunch of different parts coming and will document what happens when I change them, and see how close I can get. 

[LukeFRC]

3 hours ago, bornleft said:

and I think it is obvious that he is the only one thus far who has achieved the goal...  If you disagree,

post a link to a sound sample...

Jeez that comes across as a bit aggressive. YouTube clips of basses is never going to be a good way to make definitive decisions. 
 

ultimately if someone want the Wal tone they buy a Wal. (Which Funkle has)

if you wanted too, and knew the right people you could then clone it, but that’s not a cheap (or commercial viable option otherwise it would have been done) and gets into morally dubious areas around trade dress.

another option would be to take the concept of a Wal and upgrade it to the 21st century- and ACG made awesome things along those lines.

 

or you could get bits that are currently available and see how close you could get, which would be fun….

 

This is a thread on a forum where funkle explores the recipe that make up a bass that sounds but doesn’t look like and spends his money trying things, the rest of us are just along for the ride for our own enjoyment and to learn something. 

[HotelX]

Is the Octave guy putting Wal logos on the headstock?

[Kiwi]

I've not been that impressed by the Octave videos Ive seen so far. Theres not a lot of that growl.

[NickA]

Octave man appears to be breaching copyright with the use of a Wal logo..... plus it doesn't sound like a Wal ...plus he's playing with a pick.  Devil take him on all counts 🤣

[luthifer]

On 14/04/2023 at 09:53, luthifer said:

This is what my current FT4 treble boost filter is doing. It has a fairly soft knee (Q=0.5 I think) and the boost is settable with a trimmer. I tried going a little lower, but then the sound comes back to pretty much what you get with no LPF and some bass boost, unless you are only using the LPFs set way down low. It also has a pickup selector microswitch, and there's a big difference: The neck pickup (like Wal) gives a clean sparkle, and the bridge gives a much fuller sound. Setting the gain right is also critical or it gets nasty.

 

One thing I might do is switch to a bandpass filter with a fairly sharp peak, to accentuate the pick sound somewhere around 1.8-2.5k, but eliminate the boosted fret noise. It works pretty well with the high filter on my two-band parametric eq, but that's maybe not sharp enough.

So I just put together a bass for a guy (really good player) who has owned a lot of Wals, including one of the first double-necks. He confirmed that my treble filter is too low, so I made up a prototype for him that just stays above the filter peaks. I thought it sounded thin until he played it (he exclaimed "there it is..!"). It really adds something without being in your face. So I'm going to update the filter I think. So it confirms that the 6k-ish HPF is the way to go for a Wal sound.

Edited April 29, 2023 by luthifer

[bornleft]

When Funkle finishes his experiment, I want to take a recording of his Wal, his Wal-ish bass and the Octave bass and do a blind test....

 

Yes, Octave man should be getting a knock on his door shortly....  but as you know Wal has no time to even take a fosters, let alone 

hire US attorneys....

[luthifer]

This morning I modeled the above circuit into neck and filter circuits for simulation. I also laid out a board that will plug into the Underhill PD4 and allow me to test and listen to the actual circuits. Honestly, I don't have high hopes for these filters as a general purpose filter preamp. The filtered feedback loop appears to be used to taper the Q, and it shifts the response to the bass end as the frequency rolls down. I don't completely have my head around the feedback circuit; maybe a real EE can explain it?  The C19/R32 and C26/R44 high pass stages seem to be to cut out some of the sub bass boost from the feedback response (as well as set the impedance after the cap). It all seems like a bit of a kludge to work with the peculiarities of the Wal bass. The Q, of the bridge filter in particular, gets very high, I suspect because the response of the single coil pickups (the ones I have measured are very flat, and even have a dip in the 3-4k area). This is probably going to sound nasty with normal pickups--the high Q (>12) filters I have made tend to create "wolf-tones" at different spots on the neck, and are generally too honky and nasal in the areas your guitarist will give you dirty looks for!

 

Anyway, it seems to work well for a Wal, but it doesn't look like something that will turn any bass into one (you will still need the same neck, pickups, and pickup placement to get that!). I haven't had time to make up a plot of the bridge yet, I'll post it when I do, but in the case of the neck, you can get the same response with an FV filter by just turning down the Q a little as you roll the frequency down, and you won't have the sub-bass boost problem or the inflexible Q slope. (It would need to be re-tuned it to the Wal's ~2.4kHz upper and ~95Hz lower frequencies.)

 

Lastly, the circuit seems like it would be very noisy in several areas. I don't know what op-amps are used, so I don't have a complete understanding, but i.e. you could use a 10k for R32 and R44 and get 20dB reduction in noise at that point. The input summing circuit seems like it would be very noisy as well.

 

I learn a lot more after I get the test boards back...