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rv_bass
New
Username: rv_bass

Post Number: 2
Registered: 8-2014
Posted on Tuesday, August 19, 2014 - 5:59 am:   Edit Post

Hi,

I recently purchased an Alembic and have never used active electronics in a bass. There is a volume, pan, and tone, which I think is a low pass filter. I'm just used to cutting and boosting bass and treble on my amp (Eden WT550), so I was wondering if you may have some tips on how to properly use the low pass tone filter. I've been fooling around with it, but don't really have a good understanding of what it's actually doing. Any advice would be appreciated.

Thanks very much,
Rob
lbpesq
Senior Member
Username: lbpesq

Post Number: 5813
Registered: 7-2004
Posted on Tuesday, August 19, 2014 - 8:13 am:   Edit Post

Rob:

Welcome to the club and congrats on your new Alembic. The active electronics are indeed a different animal. Many find there is a learning curve, but once you get it you'll be able to dial in a wide spectrum of tones. The LPF cuts off frequencies higher than where it is set, while allowing all lower frequencies to pass on to the amp. My advice is to set you amp EQ flat and start playing around with the LPF. You will find that even a tiny adjustment can make a big difference. Have fun.

Bill, the guitar one
keith_h
Senior Member
Username: keith_h

Post Number: 2056
Registered: 2-2005
Posted on Tuesday, August 19, 2014 - 10:03 am:   Edit Post

Rob,
What Bill said. What model of bass did your get? Knowing this we can point you to more specific information. I use an Eden Navigator. I generally start with it flat and use it's controls to tune the rig to the room I am playing in. I then rely upon the bass controls for setting my tone. If I still can't get what I'm looking for I will tweak the Navigator to fine tune things but it doesn't

We like pictures so feel free to take some and post them under you instrument type in the Showcase.

Lastly the FAQ and Must Reads has a lot of information about the care and feeding of your new Alembic along with discussions like Joey's set up procedure, background on filters, controls, etc.

Keith
rv_bass
New
Username: rv_bass

Post Number: 3
Registered: 8-2014
Posted on Tuesday, August 19, 2014 - 6:32 pm:   Edit Post

Bill and Keith,

Thanks very much for your replies, very helpful. I have a 2005 Orion bass. I played a little tonight with the amp flat and was able to dial in a nice tone that I liked using the pickup phase and LPF controls on the bass. There is such a wide range of sounds that you can get out of this bass, it's pretty amazing really. I see a lot of fun ahead! I'll check out the FAQ/Must Read sections as well.

Thanks,

Rob
keith_h
Senior Member
Username: keith_h

Post Number: 2058
Registered: 2-2005
Posted on Wednesday, August 20, 2014 - 5:41 am:   Edit Post

Rob,
I started with an Orion too. Now I own four Alembics. Like yours mine has the upgrade to Essence electronics. Since buying it I have added a Q-switch. What it does is turn on and off a boost at the frequency where the filter is set. If I recall correctly the default without the switch is the boost is always on. I would suggest looking into it down the road as it is not an expensive upgrade and fairly easy to install.

Keith
rv_bass
New
Username: rv_bass

Post Number: 4
Registered: 8-2014
Posted on Wednesday, August 20, 2014 - 6:54 pm:   Edit Post

Hi Keith,

Thanks for the Q-switch suggestion, I'll look into it. Can you tell me; what advantage is there for being able to turn off the boost?

Thanks,
Rob
rv_bass
New
Username: rv_bass

Post Number: 5
Registered: 8-2014
Posted on Wednesday, August 20, 2014 - 6:55 pm:   Edit Post

Hi Keith,

Thanks for the Q-switch suggestion, I'll look into it. Can you tell me; what advantage is there to being able to turn off the boost?

Thanks,
Rob
keith_h
Senior Member
Username: keith_h

Post Number: 2061
Registered: 2-2005
Posted on Thursday, August 21, 2014 - 8:04 pm:   Edit Post

As I usually keep my filters wide open or close to it the Q-switch acts somewhat like a bright switch for me. With it off the notes are even across the range of play. When on with my fretted basses there is more bite when I dig in or zing with slapping/popping. On my fretless it helps pick up the fretboard slap for a more percussive sound. It can also affect the overtones that get emphasized depending upon the filter setting and what I am playing.

Keith
terryc
Senior Member
Username: terryc

Post Number: 2243
Registered: 11-2004
Posted on Friday, August 22, 2014 - 3:56 am:   Edit Post

Took me 6 months to master the 2 filters and Q's on my MK Signature.
From P bass thump, J bass honk to Gibson T bird punch and Ricky clank..it can do it all!
There was a comment on FB on a page I am on, some guy said the filters on Alembics were 'old school' and nowadays the bass/treble on todays instruments surpass this type of eq. I told him he was talking out his a**e!
rv_bass
New
Username: rv_bass

Post Number: 8
Registered: 8-2014
Posted on Friday, August 22, 2014 - 5:05 am:   Edit Post

Keith, thanks again for the clarification, very helpful! The Q-switch sounds like something I will definitely look into. Having a little more control over the brightness and bite would expand the versatility when trying to "blend" the sound using the pickup and LPF controls.

Terryc; regarding the bass/treble vs. filters issue, modern amps generally provide bass/treble cut/boost options and parametric EQ comparable to what you can find in non-filter active bass setups. I think the combination of an Alembic bass with filter controls along with an amp with all the bells and whistles really expands the possibilities for shaping the sound.

Rob
randyonbass
New
Username: randyonbass

Post Number: 1
Registered: 1-2016
Posted on Wednesday, January 20, 2016 - 10:43 am:   Edit Post

just bought a Long Scale Mark King Delux Signature 5 String. Love the bass, but I also am going through the adjustment period of LPFs and Qs, I had been using a RWG S/W/S550, and it has 18v active with bass and mid and high controls. I owned a 1977 Alembic Long Scale Series 1 until it was stolen in L.A. in 1982, so it wasn't like I had never played with the Alembic Active Electronics, but, it has been 34 yrs, so, even though I can make it make killer tones, I am still re-learning HOW I dialed in those tones. Any suggestions will be appriceated
edwardofhuncote
Senior Member
Username: edwardofhuncote

Post Number: 801
Registered: 6-2014
Posted on Wednesday, January 27, 2016 - 8:05 am:   Edit Post

Welcome to the AC Forum Randy, and welcome back to the warm world of Low-pass Filters. Congratulations on your new MK Signature Deluxe 5'r... (we LOVE pictures around here, so be sure and post us some in the Showcase section)

Regarding your question, budget some time to spend reading the FAQ section of this forum, (like at least a week) but to save you some digging, here's an older post on Filters and Q from there that should get you started:

http://alembic.com/club/messages/16271/16376.html?1206759755

PS - if your remember the serial number of your stolen bass, and better still, have a police report, I would definitely contact Mica about posting it in that section, as there are LOTS of eyes scanning the world for those early Alembics on this Board.

(Message edited by edwardofhuncote on January 27, 2016)
mario_farufyno
Senior Member
Username: mario_farufyno

Post Number: 1122
Registered: 9-2008
Posted on Friday, January 29, 2016 - 7:53 am:   Edit Post

Rob, it seems that the principle that lies behind the Alembic PU system lies in the fact that the tone of a traditional passive pickup is defined by its inductance and the way it interacts with the tone control.

Knowing that a pickup is nothing more than an electromagnet (ie: a coil around a magnet who can senses steel strings movements and translates it to voltage fluctuations), its inductance is basically defined by the number of wire turns that forms around the coil. This is what defines signal level: larger the coil, greater will be their inductance, thus generating a stronger signal.

However, greater the inductance, the more it will resist to the passage of high frequency signals and this means that a "stronger" pickup will produce less highs (you may say it'll sound less open or more muffled in way). So every pickup has its characteristic cutoff frequency above which all highs decays.

At the same time, as it passes through the tone pot, the signal has to face a capacitor and the interaction between inductance and capacitance will create a resonant peak right on that cutoff frequency. And guess what? Depending on the pickup, pots and capacitor chosen for use in a particular guitar, its tone will show more or less highs, with bigger or minor resonance. this is exactly what defines a guitar own very tone.

And here comes the idea:

Now what if you had a pickup with a very small coil? You would have a sign with extended treble response able to reveal string's higher harmonics! This by itself can already be seen as an advantage, the only drawback is that it is necessary to provide gain to the signal, since less induction generates a weaker signal, too. However this just means that you need a preamp close to the PUs and having a built-in pre allows you to control more sophisticated eq circuits right under your fingers.

In Alembic's system, they chose to use low pass filters because, in a way, it allows you to simulate different natural shades of other PU systems, since it allows to lower or raise the cutoff frequency to match the characteristics of other types of PUs and, relying on a variable peak boost, also could emulate the peculiar ressonance peak of other guitars (ie: its PU/Pots/Caps interactions). To be honest, it doesn't look that it sounds like any other guitar, to me they have their own character and nothing compares to it. In fact, we can go far beyond the tone of a "normal" guitar balancing PU pan, using the Filter with the Q engaged or not and the aid of the bass and treble boost/cut switches (not to mention the Series circuits that gives you even more tone flexibility).

By the way, Alembics are so sensitive that matters a lot the way you use your fingers and where you hit the strings, take some time to get used to it (with fresh strings and a appropriate good amp, because this bass really deserves).

(Message edited by mario farufyno on January 29, 2016)

(Message edited by mario farufyno on January 29, 2016)
jazzyvee
Senior Member
Username: jazzyvee

Post Number: 4890
Registered: 6-2002
Posted on Friday, January 29, 2016 - 11:34 am:   Edit Post

HI randyonbass, welcome back to the sound of alembic basses. I've learnt from experience there are no short cuts to learning how the filters work practically and for me at least my success came when I took a more methodical approach to what I was doing.

I worked out a tone that could do virtually all the music I was playing at the time and every time I picked up the bass I moved the controls to that point so It became second nature. Then everything else I did when trying out new tones started from there.

This meant whenever I had problems and didn't like the tone I was working with on a different song, I always had a reference point I could get back to quickly without any difficulty and know i could play comfortably with that tone.

For me on the signature bass that was, and still is, neck filter fully closed, Q- off, bridge filter fully open and Q-on. I then turn the pan pot fully to the neck pickup and then back it off towards the bridge just to the point where the crisp edge of the bridge pickup is heard in the output. That's my home point.


If you are a fan of Stanley Clarke then I would suggest using some of his albums as reference material as he really utilises a wide range of sounds in his music and see how close you can get to those sounds, I did and it certainly has given me much more confidence in making tone changes on the fly. Some of them you may never use live but it gets your head round where knobs and switches and fingers need to be for certain types of sound.


It does take a while for your instincts to realise that there is no "turning the bass up" and opening the filter doesn't add more bottom end to your signal.

Along the way you are going to find some sounds you really love. When you do, it's a good idea to get your camera out and take a snap of the positions of the knobs and your amp settings.

Another thing to be aware of is there are two blue trim pots inside the control cavity , one for each pickup pre-amp which as well as letting you adjust the output level of your bass, it allows you to bias the output of your bass so that when for example you have the pan in mid position, there is more of either the neck or bridge signal in the output. I personally have mine set exactly the same for both pickups.

I hope that helps.

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