• TalkBass has been independent since 1998. Add your voice.
    Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
    Join free Log in
    Want zero display ads or expanded classifieds tools? Compare plans.

ACG onboard preamp (ACG/John East design)

#141
emjazz said:
Man, I'm so glad that you like it. I was hoping that after my PM's with you that I wouldn't be wrong....of course I didn't see that happening really. :D Have fun!
Click to expand...
Yes your help has been very kind,i love the eq,it makes the jazz sound like a "super"jazz,and then you can change it so that it doesn't sound like a jazz at all!!how many eq,s do that!it's worth every penny,or doller;)i'm having fun alright!!!thanks again,Julian.
 
#143
Just to update re the fitting of another ACG02, this time in my mates Spector Euro LX5. That makes it my 4th ACG02 fitting and the 1st with active pickups.

Initial impressions are very good with much more tonal depth available now.

Installation thread is here:

Link Removed

Oh and in case I haven't posted this before I aquired an ACG01 too.

How?



3177457260_7fec9caee6.jpg


3177457268_18abdcf3e5.jpg


Peter
 
#144
Skelf said:
It does take a change in thinking to get the best from the pre-amp if you have only used cut/boost pre-amps but with a little time you can get some excellent tones from it. From customer feedback after the initial learning curve people seem to find what they are looking for plus several other tones they did not know they needed.
Cheers
Alan
Click to expand...

Right! That's it, I'm sold on it!! When will you have some more in stock?
 
#149
I just had Alembic pickups and an ACG 5-knob pre installed for me on my 5 string a few days ago, and tried using it on two gigs and for some test recording over the weekend.

I'm still getting used to all the tonal possibilities, but I love the tones I'm getting already. I have run into a few problems, however:

1. Output level is quite low (almost inadequate), even with both internal trimpots maxxed. I had my repair guy install it with only one battery, but now I'm wondering if converting to 18v would produce significantly hotter output?

2. I think I understand the concept of the bass filter frequency control, but at any setting less than about 70% clockwise, this knob almost seems to function like a volume control. At low settings, even my B string becomes very quiet. Fortunately, things start to sound GREAT when I turn it up to about 80%, but that seems like a narrow useful range for this knob.

3. When experimenting with the bass filter, I tried turning the overshoot peak all the way up to help me zero in on the desired setting for the frequency control, but when the frequency control is turned to its fully open (clockwise) position with this amount of boost, a horrible shrieking sound (like feedback) results! :eek: I would never use such an extreme eq setting in an actual playing situation, but it scares me that such a sound can occur.

Any help or advice on these issues would be much appreciated. :help:
 
#150
1) Have you used the Alembic pickups with any other preamp? I thought I heard that the passive output of Alembic pickups is fairly low, and the Alembic preamp is designed to compensate for that, but I have no personal experience with them. In any event, I'm pretty sure the 18v option on the ACG preamp is like most preamps--it's intended to offer more headroom and/or battery life, not boost the output level.

2) Remember, as you're turning the bass filter frequency down, you're cutting out a larger and larger percentage of the string's frequency range--I'm not sure exactly what the minumum cutoff is, but I seem to recall it going down well under 100 Hz--and that can definitely affect the overall output. With my Wals, I tended to leave the master volume set at about 60-70% most of the time, so that I had "boost room" available for the volume loss that occurred when I turned the tone control way down into "dub territory".

Mike
 
#151
Hi
Could you tell me how old your Alembic pickups are as the older versions have a very low output but I think the newer versions are much higher.
Also could you tell me what rig you are using the bass with.
This feedback type sound is new to me I have never been able to make the pre-amp do this. When testing any pre-amp I have installed I always go through the most extreme settings to make sure every thing is working and to date I have never had this happen. Is it possible it is happening in conjunction with another part of your signal chain. It would be possible if there was a lot of gain all the way through the system. In the pre-amp and amp etc.
Any info you can provide would be useful to try and work out what is going on.
 
#152
Skelf said:
Could you tell me how old your Alembic pickups are as the older versions have a very low output but I think the newer versions are much higher.
Also could you tell me what rig you are using the bass with.
This feedback type sound is new to me I have never been able to make the pre-amp do this.
Click to expand...

Thanks for your prompt reply, Alan. I'm impressed by your customer service. Unfortunately, I don't know the vintage nor exact origin of my Alembic MXY56 pickups. I bought them used over the internet, and I believe they have changed hands a few times before. They are fairly well worn, and could easily be over 10 years old. I have tried the bass now through several different systems: a small Fender practice amp at low volume, a Carvin PB500 amp/Acme Low BII cab at low to medium volume, straight into PA system via DI, and direct into to ProTools via DI. It only produced the feedback sound twice, once through the Fender amp, and once through the Carvin/Acme rig. On both occasions, amp volume was low but I was sitting in close proximity to the amps, and the volume on the ACG might have been max or close to max. Feedback ceases immediately when I turn the bass filter frequency control back counterclockwise. I am avoiding that setting on the bass now because it hurts my ears and might damage the amps. I am not discounting the possibility that these new pickups might be prone to this sort of feedback. My biggest concern is really about the output level. Will 18v make much difference?
 
#153
I've used the ACG preamp (02) for a while now...a year maybe? I've never experienced the feedback sound that you're having. Also, I find, even at 9 volts with pickups that aren't considered high output, that there is more gain available than I need out of this preamp. It can get much louder volume wise than I'd ever want out of a preamp. There's either something going on with the pickups or the way the preamp is wired to everything.
 
#154
Hi
We have used the pre-amp with Alembic pickups this was done while we were sorting out the pre-amp for the Stanley Clarke basses. These would be pretty new pickups and having spoken to John about this he tells me the earlier pickups were very low output which was compensated for with the Alembic pre-amp,it had a lot of gain to boost the signal up to a usable level. I am unfortunately not that familiar with the Alembic pickups to give you a definite answer on this aspect of the problem. It is certainly possible that proximity to the amps could be the problem in conjunction with the pickups. I will continue to look into it and see if I can find out what is happening. I know me saying it has never happened before is little comfort but it is something we have not heard of before.

18 volt will not increase the output only the headroom within the system. It would do no harm to try it but I don't think it would sort the feedback issue.

Alan
 
#155
I don't really want to mess with the good tone I'm getting from this bass now, but I wonder if there is any kind of supplementary boost circuit that might enhance output without affecting tone adversely?

I have one other question about the filters. I read somewhere that the gain knob for the treble stack is a boost-only function, but if that's the case, then why does the pot have a center detent? Is the center detent a flat setting, or a "medium" amount of boost?
 
#156
I've been living with the ACG EQ-01 (in an ACG bass) for the past couple of weeks.

The flexibility of the pre really is amazing. OK, it does take a little while to find out what effect each control has but that's time well spent. I suppose the best thing I can say about it is that I'm saving to have an ACG 02 put into my Sei bass.

A great product and definitely something to consider if you feel that your bass sound isn't up to scratch.
 
#157
bassandbeyond said:
I don't really want to mess with the good tone I'm getting from this bass now, but I wonder if there is any kind of supplementary boost circuit that might enhance output without affecting tone adversely?

I have one other question about the filters. I read somewhere that the gain knob for the treble stack is a boost-only function, but if that's the case, then why does the pot have a center detent? Is the center detent a flat setting, or a "medium" amount of boost?
Click to expand...

I will ask John if he has a module that could boost the pickups output.
The centre detent is merely a reference mark because as you say it is boost only 0 to +18. This allows you to remove the treble filter completely should you not need it.
Alan
 
#158
Skelf said:
I will ask John if he has a module that could boost the pickups output.
The centre detent is merely a reference mark because as you say it is boost only 0 to +18. This allows you to remove the treble filter completely should you not need it.
Alan
Click to expand...

Hey Alan, pertaining to my next Ristola with your preamp in it, will I be able to go without the treble stack completely...as in, remove it from the preamp? I don't use the treble stack at all. Thanks.
 
#160
Thank you for your assistance, Alan. I'm sure my issues can be sorted out....at least I'm able to get adequate level for a very nice recorded sound, so it will make a great studio bass.

I wonder if it's possible that there may be a defect in my bass filter? As I mentioned before, I don't seem to able to boost low end at all with this control, it only works to accentuate mids.
 

Latest posts

Top Bottom
Back