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Username: esa

Post Number: 11
Registered: 8-2010
Posted on Tuesday, August 27, 2013 - 12:16 pm:   Edit Post

Hi, everyone.

I am hoping that you can help me figure out a solution to a problem I'm having.

I am trying to run my SF-2 with my F-1X, and it's just not happening.

If I try running the SF-2 in the FX-loop of the F-1X, I get a HORRIBLE and LOUD distortion, without even playing a note. If I run it from the full-range out, it works, but it clips VERY easily.

Why won't it work in the loop? I would think that these two units should work seamlessly together.

In full range mode, why is it clipping so much and so easily?

The whole rig works great when the SF-2 is not connected, but when it's hooked up, the rig becomes really testy and delicate.

These problems are present regardless of the EQ settings on the F-1X. (I never had any problems like this when I ran the SF-2 with my Eden WT-800.)

Any ideas? I'm actually considering taking the SF-2 out of the rig! Help!

Thanks in advance!
Username: esa

Post Number: 12
Registered: 8-2010
Posted on Tuesday, August 27, 2013 - 12:25 pm:   Edit Post


If I run my tuner (Korg DTR-1) in the FX-loop *before* the SF-2, it works fine...

Username: mica

Post Number: 8017
Registered: 6-2000
Posted on Tuesday, August 27, 2013 - 3:31 pm:   Edit Post

The effects loop in the F-1X is a low-level effects loop. If you choose to use the SF-2 in it, you MUST keep the SF-2 levels VERY low since the SF-2 is a high-level effector.

You can use the SF-2 directly after the F-1X as well.
Username: esa

Post Number: 13
Registered: 8-2010
Posted on Tuesday, August 27, 2013 - 4:46 pm:   Edit Post

Thanks, Mica.

But why does running a tuner in the loop before the SF-2 allow for "normal" levels?

...and why would running the SF-2 after the F1-X cause clipping at low gain (i.e. 1, or less, on the volume dial)?

The SF-2 seems so touchy with the F-1X - I'm wondering if it needs service.
Username: davehouck

Post Number: 11154
Registered: 5-2002
Posted on Tuesday, August 27, 2013 - 5:36 pm:   Edit Post


- when you say the volume is at 1, are you talking about the F-1X or the SF-2?

- how do you have the SF-2 setup? Which inputs and outputs are you using? What are the volume levels?
Username: esa

Post Number: 14
Registered: 8-2010
Posted on Tuesday, August 27, 2013 - 6:39 pm:   Edit Post

Hi, Dave.

"1 on the volume" refers to the F-1X setting when the SF-2 is run from the "full range" output. Higher than 2 on the F-1X in that configuration causes the SF-2 to clip, badly.

For testing different connections, I have the EQ on the F-1X set at 2-10-2. Neither the deep switch nor the bright switch are engaged.

I am running the SF-2 in mono mode (Ch. A in; Ch. B out), and the overall volume is very low - I don't want these enormous clipping spikes to damage my speakers... or my ears.

On the SF-2, I have the Input Gain at 5-6 (though I normally ran it wide open (10) with my previous rig).

Because of this issue, I'm not even using the filter settings right now. Both filter gains are set to 0. (The problem is in the input stage, not the output.)

It sounds like an impedance issue, but I wouldn't suspect that, given that these devices are practically made to work together.

Username: davehouck

Post Number: 11155
Registered: 5-2002
Posted on Tuesday, August 27, 2013 - 7:50 pm:   Edit Post

A couple things to try just to see what happens.

- have you tried putting the SF-2 first, then the F-1X in the chain?

- have you tried coming out of one of the crossover outputs of the F-1X and then into the SF-2?
Username: esa

Post Number: 15
Registered: 8-2010
Posted on Tuesday, August 27, 2013 - 9:06 pm:   Edit Post

Thanks for the suggestions, Dave.

I'll try them out tomorrow and report back.
Senior Member
Username: jazzyvee

Post Number: 3588
Registered: 6-2002
Posted on Tuesday, August 27, 2013 - 11:07 pm:   Edit Post

Here is Posting by Dave with links to some threads on the SF-2. There may also be some reference material or fixes in some of those, though I haven't checked.

Username: esa

Post Number: 16
Registered: 8-2010
Posted on Wednesday, August 28, 2013 - 3:44 pm:   Edit Post

Having the SF-2 first in the chain works fine (no clipping). It's a bit of an inelegant solution, though (having a cable run from the back of the rig to the front), plus I far prefer the tonal characteristics of having the SF-2 after the F-1X.

Having it in the FX-loop (after the tuner) works fine, too, but it adds a lot of hiss in that configuration.

Using the X-over outs on the F-1X does not introduce clipping, until the volume on the F-1X exceeds ~5... which is about where I can run the volume if the SF-2 is not in the chain.

I think I have tried these two units in every possible configuration, and the conclusion seems to be that the full-range output of the F-1X is simply too hot for the input of the SF-2.

I can remedy this by placing a compressor between the two units, but I still have to be very careful with gain-staging. The only other workable option seems to be to keep the SF-2 in the FX-loop (after the tuner), and try to ignore the hiss... or, just take it out of the rig.

Thanks! I'm perusing the links now.
Username: bonesrad

Post Number: 99
Registered: 5-2002
Posted on Wednesday, August 28, 2013 - 4:40 pm:   Edit Post

This is very curious. I run my SF-2 Channel A into my F-1X FX-loop. No problems. I have the direct gain all the way up and the filter gain at around 3:00. It seems to sound great.

Senior Member
Username: sonicus

Post Number: 3010
Registered: 5-2009
Posted on Wednesday, August 28, 2013 - 4:47 pm:   Edit Post

In my all Alembic rig I have had the best results with an SF-2 used
first in the signal chain directly after the instrument. One of my favorite signal chains with SF-2 would be would be Series I in Stereo going to IN-2 to SF-2 to F-2B to Power Amp to Speakers . (stereo signal path all the way). I like to think of the SF-2 as part of the instrument when I engage it's use. In a variation I have also substituted two F-1X units instead of the F-2B and made use of the balanced XLR outs to interface to a recording console as well as the XLR outs on the IN-2 in order to have a choice between pre and post EQ attenuation . I had excellent results in both variations and also had a microphone in the mix.. You will be sure to make a producer in a recording studio raise his eyebrows for an extended time when he walks in and sees 5 channels on the console with your bass signal .LOL _______

Sonic Regards ___
Username: esa

Post Number: 17
Registered: 8-2010
Posted on Wednesday, August 28, 2013 - 8:30 pm:   Edit Post

Do you have anything else in the loop with the SF-2? I can't get the direct gain past 2 or 3 on my SF-2 when it's in the loop by itself.

That's quite a configuration! I'll have another go at putting the SF-2 before the F1-X, but I've always loved having the SF-2 altering the EQ'ed signal from the pre-amp. That, and the fact that I really don't want to have a line running from the back of the rig, around the rack, and into the front input of the F1-X. But, it will work that way, I may have to.
Senior Member
Username: elwoodblue

Post Number: 1500
Registered: 6-2002
Posted on Wednesday, August 28, 2013 - 11:33 pm:   Edit Post

I use my SF-2 after the F-1X ...sounds godly .
Chest thumping AND HiFi .
I run the SF-2 in Stereo, one channel for each cab,
lowpass for the 15,high pass for the 12(or sometimes 10's).

The SF-2 outs go through the Lexicon MX400 before the power amp.

I think most the settings in the picture are typical of where I run things.

Intermediate Member
Username: jon_jackson

Post Number: 178
Registered: 12-2008
Posted on Thursday, August 29, 2013 - 5:18 am:   Edit Post

I use two F1-X units with the SF-2 (in stereo) connected through the effects send/return loop in the respective F1-X without noise or gain problems:

DS-5R (bass & treble) > (2) F-1X (effects send) > SF-2 (stereo A & B) > (2) F-1X (effects return) > (2) F1-X (currently using the full range outs) > Power amps.

The tuner is fed from the "bass" F-1X, either the low pass crossover or the full range out depending upon which is not in the main signal path at the time.
Username: davehouck

Post Number: 11158
Registered: 5-2002
Posted on Friday, August 30, 2013 - 2:15 pm:   Edit Post

Esa; I'm assuming you are coming straight out of your bass and into the F-1X; no effects in between them. If you are using an Alembic bass, you might want to check the gain pots inside the control cavity; if they are all the way up, you might want to turn them back some so you're not sending too much signal to the preamp.

My recollection from several years ago is that my rig then was F-1X > Compressor/Limiter > SF-2 > Power Amp. (I think I might have had a reverb/delay unit in the loop.) And my recollection is that I had the chain set up for the purpose of maintaining a good control over the gain structure. So I would suggest you keep working with different combinations until you find something that sounds great and works well. (I'm using an F-2B now, and my volumes are at 4.5 and 5 on its two channels.)

So my suggestion would be to try backing off the internal gain pots on your bass, then into the F-1X, then from the full range out into the compressor/limiter, then on to the SF-2; and keep experimenting until you find the right combination of gain settings to get the tone you want. And as others have suggested, you might want to also experiment with having the SF-2 first just to see if that opens up some tonal possibilities that you might find appealing.
Username: esa

Post Number: 18
Registered: 8-2010
Posted on Friday, August 30, 2013 - 3:14 pm:   Edit Post

Thanks, Dave.

You are correct in assuming that I have no effects between the bass and the F-1X. I have three basses (one Alembic), and none of them have a very hot output - the problem definitely came from the output of the F-1X, or the input of the SF-2.

I had put the whole thing out of my mind yesterday, but I came back to it today, and just started over - something very curious happened: I plugged the SF-2 into the full-range output of the F-1X, and there was no clipping.

I can now run the F-1X volume up to "5", and the SF-2 does not clip any more. I tried this a dozen times during the week, and I consistently got clipping once I passed "1" on the F-1X volume knob... but now it's gone.

I have no explanation for this - same basses, same cables, same player, same gear all-around, but the problem is gone.

Any ideas on why that might have happened?

I'm now running: bass > F-1X > SF-2 > compressor > power amp ...and it's working fine.

I am tempted to put the SF-2 into the F-1X loop again to see if that problem has vanished, too, but since I prefer the SF-2 after the F-1X, and I don't want to screw it all up again, I think I'll leave it as it is. This is the set-up I was gong for all along.

If the problem rears its head again, I will just swap the compressor and the SF-2: bass > F-1X > compressor > SF-2 > power amp
...but I'm hoping that this current configuration will continue to be problem-free.

Thanks to everyone for all the input and suggestions - it's good to know that we have a community of Alembic brethren out there who will help when problems arise!
Senior Member
Username: elwoodblue

Post Number: 1501
Registered: 6-2002
Posted on Friday, August 30, 2013 - 10:55 pm:   Edit Post

Whew. good news,

have you read this ?

let us know if anything changes,

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