Ampeg Isovent - Jack Plate Circuit Board.

[DJ Bebop]

The OP mentioned in a post that his favorite band used these (like 30 years ago, or something). But, they (Metallica, IIRC) quickly moved onto better sounding gear once they realized their mistake.

No matter who our favorite artists are. If we watch over time. There is a reason they move on in their equipment
choices. We may not like it but, they do

 

[DJ Bebop]

Every time I see him write ReWire, I think of this:
[Invalid or Expired Link Removed]
Product placement?

 

[DJ Bebop]

I find this thread sad. A lot of us come here to help our fellow bassists get around problems they encounter. It's doubly sad that the OP will not listen to the good advise he has been given by very knowledgeable folk and is stuck in a rut about the crossover board. I guess we'll see how it goes without said board. <sigh>

 

[DJ Bebop]

That is not how electronics like this work, especially the electronics you posted pictures of.

 

[daveman50]

You're all wrong. The problem is the Lightbulb!!!! (Aged Horse, I'm really surprised you did not spot this.) This can only be Observed if the Cabinet is Sealed!!!! The OP should seal himself inside the cabinet, have someone play the F Bomb, and see if the lightbulb lights up. Then the problem will be solved. (N.b., this method similar to figuring out if someone's a witch - see if they float.)

 

[BioWeapon]

I want to be surprised by threads like this, but realistically I've seen too many of them to be even mildly shocked anymore. At least there's funny bits

 

[NKBassman]

No matter who our favorite artists are. If we watch over time. There is a reason they move on in their equipment
choices. We may not like it but, they do

Yeah, usually endorsement deals and marketing. Probably why Metallica was (allegedly) running with the Isovent in the first place.
I saw a vid recently of them on the Howard Stern show where they all had giant double stack guitar cabs in this tiny studio space, obviously just there to hide the Axe FX racks.

 

[fdeck]

The DK Effect is my favorite thing that I learned last year.

You think you learned it.

 

[NKBassman]

You think you learned it.

I became aware of it . I don't purport to know much any detail about it from the psychology side of it. I'm firmly at the bottom of the trough of despair.

 

[S-Bigbottom]

Yea I know about Trouble Shooting. I used to work on M1 tanks in the Army, and I got pretty good at finding and diagnosing problems with tanks

Than understand that what you are doing with this crossover thing is like trying to fix the tank not going into reverse by changing the periscope in the turret.

 

[agedhorse]

Than understand that what you are doing with this crossover thing is like trying to fix the tank not going into reverse by changing the periscope in the turret.

Or changing the rear LF antenna because it's located on the rear of the tank, thus the direct connection to the symptom (in a perverse, obtuse kind of way).

 

[esoxhntr]

You've all missed the real issue... the lightbulb. The lightbulb being integrated into the crossover means that certain frequencies - most likely the F we are talking about - are travelling at light speed, while the majority of the frequencies are travelling at the speed of sound. No wonder there is a problem. It's not the cabinet design (clearly perfect), it's not the low damping factor of the amplifier (how could that be an issue?)... simply smash that light bulb with a hammer and this issue will magically disappear... Poof!

 

[NKBassman]

You've all missed the real issue... the lightbulb. The lightbulb being integrated into the crossover means that certain frequencies - most likely the F we are talking about - are travelling at light speed, while the majority of the frequencies are travelling at the speed of sound. No wonder there is a problem. It's not the cabinet design (clearly perfect), it's not the low damping factor of the amplifier (how could that be an issue?)... simply smash that light bulb with a hammer and this issue will magically disappear... Poof!

Quiet you! We’ve already got him to acknowledge that the light bulb is part of the tweeter circuit.

 

[esoxhntr]

Quiet you! We’ve already got him to acknowledge that the light bulb is part of the tweeter circuit.

My lips are sealed.

 

[DJ Bebop]

F BOMB!

 

[mexicanyella]

The DK Effect is my favorite thing that I learned last year.

Holy Moly, the wiki entry on the D-K Effect reads like an article from The Onion!

 

[Nicholas Orick]

Than understand that what you are doing with this crossover thing is like trying to fix the tank not going into reverse by changing the periscope in the turret.

It isn't called a Periscope. Tanks use View Blocks and a Gunners Primary Sight.

A couple of you guys offered good advise.

The rest of you offered Nothing of real value towards solving the problem.

Doesn't matter.

I like the Isovent, have already decided on a course of action based on Real and Sound advise, and have already taken the Isovent to a friend's place fir modification.

We will soon see how it goes.

.

 

[Nicholas Orick]

Just a passing question: Are both drivers in the lower bin working? If one of the two drivers is open-circuit, it would result in greatly different behavior than the design intent.

Both work.

 

[Nicholas Orick]

So.... what point are you trying to convey by publishing all those pics of PA cabs?

Another idea.

Take an Array Module and use that.

This is in response to a question regarding using something "more modern".

 

[NKBassman]

It isn't called a Periscope. Tanks use View Blocks and a Gunners Primary Sight.

A couple of you guys offered good advise.

The rest of you offered Nothing of real value towards solving the problem.

Doesn't matter.

I like the Isovent, have already decided on a course of action based on Real and Sound advise, and have already taken the Isovent to a friend's place fir modification.

We will soon see how it goes.

.

What modifications are you making.
How did the circuit board surgery go?