Author Topic: Essence Q-Filter Control--How does it work? (Read 386 times)

jrbrown · « **on:** October 25, 2003, 08:04:11 PM »

- Could someone please explain in detail how the Q-Filter and Q-Switches work? Now before you say, Search the board, I did a search and received more non-filter related hits than I care to go through.

- Also, what would be a good electronics up grade for the Alembic Essence?

- Anyone ever install a Bart preamp in an Essence? I heard that it works wonderfully.

(Message edited by jrbrown on October 25, 2003)

David Houck · « **Reply #1 on:** October 26, 2003, 08:21:28 AM »

Basically, the filter control is a low pass filter; as you roll it back it lowers the point at which it passes low frequency signals and blocks high frequency signals. To quote Mica, the range is from 350Hz-6KHz. Wherever you set the filter, only frequencies below that cutoff point are passed. The Q switch works in concert with the filter and provides an 8db boost at the cut off frequency you've set with the filter. When the switch is off you get a flat response on to the filter setting. Again to quote Mica, the Q affects mainly the attack portion of the note.

Essence controls have a filter control but no Q switch; for an Essence the Q is always on. A good electronics upgrade for an Essence is to add a Q switch. It is relatively inexpensive and Alembic will send you installation instructions. Beyond that, any upgrade is a bit more problematic because of the lack of available room in the control cavity. Also for any other upgrade Alembic will want for you to send the bass to them for the upgrade. For instance a good upgrade might be to add bass and treble boost/cut switches. But again, you are looking at sending the bass to Alembic and probably modifying the control cavity.

I would imagine the vast majority of the members of this group would not recommend replacing Alembic electronics with Bart electronics. Bart makes great preamps, but part of the reason for buying an Alembic is the electronics.

Personally, my main bass is an Essence and I know how frustrating Essence controls can be. With the Q always on, I find the boost to be generally unworkable at lower filter settings; thus I usually leave the filter all the way up and adjust my tone with my F-1X and SF-2. I have not yet added the Q switch since I am planning to send my bass to Alembic at some point in the future. However, I do have a fretless that has Europa controls and the Q switch on that bass does make a difference. Being able to turn the Q off when rolling the filter back to lower settings does give a smoother sound.

I would guess that not all Essence owners would agree with my comments; I'm sure many are happy with the tone they are getting now. Tone is very subjective and is also influenced by what your ears hear and how damaged your ears are after years of repeated assaults from high frequency PA feedback, as mine admittedly are. But if you are having problems getting useful tones out of your Essence, then a good first step would probably be adding a Q switch.

Dave

jrbrown · « **Reply #2 on:** October 26, 2003, 11:08:47 AM »

Thanks for taking the time to explain the operation of the Q-Filter and switch. To recap: If I have my Essence Q-control full up, I am allowing everything from 6K down to pass with an 8db boost at 6K. Right? Therefore the control is simply a More-highs control and has no effect of the freqs below 350Hz.

The only problem I'm having is that the 8db boost on the high-end is over powering the low freqs.

I'll order and add the switch to kill the 8db boost on the high end. Assuming that the switch is a open/close type, shouldn't I be able to jumper two wires together until the switch arrives?

David Houck · « **Reply #3 on:** October 26, 2003, 01:02:32 PM »

I think your recap is correct. As I understand it, the kit is more than just the switch; there is a new capacitor as well, plus one existing capacitor must be removed. So I don't think jumpering wires would work or would be a good idea. I'm guessing that if you call Alembic and order the switch, they should be able to get it out fairly quickly (I'm only guessing). I'm also guessing that you could ask them to ship it Fedex for next morning delivery.

Dave

jrbrown · « **Reply #4 on:** October 26, 2003, 01:15:33 PM »

I'm not in a hurry for the switch. My Essence bass sounds very good as is. The only adjustment I have to make is an increase in bass on my F-1X. However, I would like to be able to control more at the bass. I'll order the Q-switch on Monday.

Thanks

Oh, Here's my new bass: Bocate top amd Zebrawood headstock I think.

JB

rami · « **Reply #5 on:** October 26, 2003, 03:53:20 PM »

Hi JB,

Your Essence is a real beauty!

The Essence I use most has the Rogue/Europa electronics upgrade. Not only do you have a Q switch, but you also have Bass & Treble switches. I think this is the best overall electronics package.

Here's my pic:

jrbrown · « **Reply #6 on:** October 27, 2003, 06:17:48 AM »

I wonder how much it'll cost me to get that upgrade? Sad thing is, I don't think mine will take that upgrade. My output jack is on the top.

I think I'll try the switch first. I really don't want to send the bass cross-country for a month. I can do the work myself if I had the parts.

essencetimestwo · « **Reply #7 on:** November 02, 2003, 07:40:14 PM »

Can somebody let me know how much a Q switch upgrade for my Essence bass would be and if it is something that I can do or should I let Alembic do it. I live in northern California so it would be easy for me to visit Alembic to get it done. Also I am curious about changing the finish on the back of my neck to a more natural feel. I would only let Alembic do this for me. If anyone knows if this can be done and how much it would cost please let me know.

wayne · « **Reply #8 on:** November 03, 2003, 05:45:21 AM »

Simon-

Changing the finish is very simple. To get the satin finish on the neck: 1) tape off what you want to remain glossy (use the low tack blue tape from 3M); 2) lightly sand everything else with 600 grit wet/dry sandpaper; 3) buff what you sanded with 0000 steel wool; 4) use a tack cloth to clean up all the dust, and presto! you have satin neck finish.

It's nothing to be afraid of - I did it to my Series I myself with no ill after effects.

Good luck.

C-Ya..............wayne

valvil · « **Reply #9 on:** November 03, 2003, 04:44:32 PM »

Adding the Q switch to an Essence is 75$.

Valentino

jrbrown · « **Reply #10 on:** November 04, 2003, 05:28:32 PM »

I installed the Q-switch tonight! Well worth it! Makes me wonder why it isn't a standard feature on all Essence basses.

David Houck · « **Reply #11 on:** November 04, 2003, 06:12:34 PM »

Nice job James, looks good. There's not much room in there; did you have any trouble locating a good place in the cavity to put it? And what do you think of the tonal differences? One of these days I'll have one in my Essence.

jrbrown · « **Reply #12 on:** November 04, 2003, 07:37:58 PM »

It was an easy install. There's PLENTY of room for the switch. The tonal difference is subtle yet very effective.

Switch on: Aggressive and Glassy
Switch off: Bold and Smooth

JB

(Message edited by jrbrown on November 06, 2003)

essencetimestwo · « **Reply #13 on:** November 05, 2003, 11:48:07 PM »

JR,

How was the install of the Q switch? Was it fairly easy to do? Is there any particular reason you placed it so close to the tone control? Was that personal preference or was it the only place it would fit? I am looking to do this to my Essence so let me know. Thanks!

jrbrown · « **Reply #14 on:** November 06, 2003, 05:07:58 AM »

The installation is not difficult:
- The switch connects to the Q-filter module. You have to pull the module out to do this.
- Drilling the hole can be a challenge. You must be very careful to not splinter the finish.
- Installing the switch so close to the filter control is actually more difficult than installing it further away; there's plenty of room.
- The placement is perfect! I don't have to look down for the small switch. When I reach past the balance control, my middle finger lands on the filter control knob. That puts my index finger on the switch.
My daughter illustrates:

(Message edited by jrbrown on November 06, 2003)