Needed BA438/A info

[ForthMonkey]

Hi,

I have a question.Can i use this signal amp on EQ circuit? I built BA438/A and i tried to build low shelf and it was good to me.

Now i want to build two BA438/A and then making "1073ish" eq without inductors.Is this good idea? Or useles?

By the way i need circuit for Neve style eqs.
Thanks!

 

[Tekay]

The BA438 was used in the 31105 EQ and will work just fine in a 1081 as well.
You can use it in the 1073 circuit. Use pin 2 as input, ground to pin 1 and feed pin 7 to ground via a 150uF/16v cap. This is how it was used in the 3116

 

[ForthMonkey]

The BA438 was used in the 31105 EQ and will work just fine in a 1081 as well.
You can use it in the 1073 circuit. Use pin 2 as input, ground to pin 1 and feed pin 7 to ground via a 150uF/16v cap. This is how it was used in the 3116

Thanks!

But i can't find EQ section schematic of 1073.Is there any schema easy to understand?

 

[Tekay]

All old Neve schematics are block diagrams, you need to re-draw it to get an overview.

 

[ForthMonkey]

All old Neve schematics are block diagrams, you need to re-draw it to get an overview.

Ohh i understand.I want to built like Poorman's Pultec without inductors.So i can use only BA438,right?Should i use other cards?

 

[Tekay]

If you mean a 1073 without the mid section, yes. Try to find a copy the 3116 schematics, it's just a high /low shelving EQ.
If you can't find it, pm me and I will send you a copy.
/
Thomas

 

[ForthMonkey]

If you mean a 1073 without the mid section, yes. Try to find a copy the 3116 schematics, it's just a high /low shelving EQ.
If you can't find it, pm me and I will send you a copy.
/
Thomas

Thanks but i will build it with mid section.I mean "poor". ;D Do you have 1099 schematic? I need to see and understand.

 

[Tekay]

Don't have the 1099 schematics but it's more or less a 1073 without the line input. Or a 1063, which has some extra gain steps.