Studer 169/961 EQ (again) - stepped + midrange + 4x in 1RU

[oran.outan]

I missed it ! Sorry. I'm not always looking at the thread. I recommend you tag the people, like this they will have a 'pop up'...
I still have some... no more with edge connector but with 500 style shape.

NO, they're not at all the same.
The one I made is only the High and Low band and the schematic is quite different as you can change the frequencies band which are fixed on the Gustav one (20hz / 20khz). but you have an adjustable mid band...
What make this one in between is the fact you can have few settings for each band and cover (mostly) all the scale.

The 1st 'problem' mixing both Gustav and mine will be the crossover between the bands : the low ones can't come over the mid one's / the mid not over the High. Each band scale will have to be pack tightly... or less band...
On mine I think I never used the 230 freq on the Low and the 2K on the High, so I don't think it be a big loss.
If you look at this EQ (1st post) : Low: 25Hz, 50Hz, 120Hz - Mid: 145Hz, 250Hz, 550Hz, 1,5kHz, 3kHz, 6,2kHz - Hi: 12kHz, 16kHz, 20kHz --> they're not crossing...
The second problem is to make fit 6x switches on a 500 series size. It will need to go for small size switches, mostly grayhill which double/triple the cost. 6x Lorlin never fit.

Good building anyway !

 

[PatchDog]

I missed it ! Sorry. I'm not always looking at the thread. I recommend you tag the people, like this they will have a 'pop up'...
I still have some... no more with edge connector but with 500 style shape.

NO, they're not at all the same.
The one I made is only the High and Low band and the schematic is quite different as you can change the frequencies band which are fixed on the Gustav one (20hz / 20khz). but you have an adjustable mid band...
What make this one in between is the fact you can have few settings for each band and cover (mostly) all the scale.

The 1st 'problem' mixing both Gustav and mine will be the crossover between the bands : the low ones can't come over the mid one's / the mid not over the High. Each band scale will have to be pack tightly... or less band...
On mine I think I never used the 230 freq on the Low and the 2K on the High, so I don't think it be a big loss.
If you look at this EQ (1st post) : Low: 25Hz, 50Hz, 120Hz - Mid: 145Hz, 250Hz, 550Hz, 1,5kHz, 3kHz, 6,2kHz - Hi: 12kHz, 16kHz, 20kHz --> they're not crossing...
The second problem is to make fit 6x switches on a 500 series size. It will need to go for small size switches, mostly grayhill which double/triple the cost. 6x Lorlin never fit.

Good building anyway !

Merci pour l'explication. Ah yes, yours and this one are missing the mid band. I'm guessing that was due to space considerations as I've seen others build Audiox (non mastering version) but with stepped controls including mid-band. The band 'cross-over' problem seems like not such an issue to me

In the end I've decided to go for the standard Audiox design with 3 frequency band selects added via sub-miniature toggle switches for the Low & High shelf (20Hz, 60Hz, 120 Hz / 12k, 16k, 20k). I modelled it in Blender to see if I could make it all fit in the chassis in the area I wanted it, which it can, just!

I was opening up some behringer modules the other day, and they use pretty small switches, they're not grayhill of course but small footprint. 17mm x 17mm at the base. You could fit 2x side by side in a 500 series panel, not sure how much positions you can get with these. But you could easily fit the 5 you need on a single panel with plenty of space left for the dual deck mid band switch, and for much less than Grayhill prices. It looks like these types:
https://www.mouser.co.uk/ProductDet...-20F0A-N9-N-027?qs=8%2Br4Hz5Xir8jgfyVwPHVzQ==

 

[oran.outan]

HI

I see the modding for the 169 and sure It's a great feature for that device. Giving more flexibility.

I doesn't know about that alpha Switch but that one is non shorting (BBM) and it need shorting (MBB), otherwise you will have a 'pop' when turning the switch.
but I will look deeper on them.

 

[TheSpeckySegg]

What did everyone do for a power section for the 19" version with all 4 eq units? i'm still fairly new to this and the project doesn't seem to list a power solution.

 

[oran.outan]

if that the question, you need a linear PSU, +/- 15v. Globally a 2x18v (2 x 15V at least ) transformer and an AC/DC circuit like the POSNEGPSU-rev02 from Volker which I recommend (white market).

 

[TheSpeckySegg]

if that the question, you need a linear PSU, +/- 15v. Globally a 2x18v (2 x 15V at least ) transformer and an AC/DC circuit like the POSNEGPSU-rev02 from Volker which I recommend (white market).

https://capi-gear.com/catalog/product_info.php?products_id=567

Could I use something like this instead? External would work a lot better for me!

 

[oran.outan]

Yes you could but no need of the +48v.
As it’s not a linear Psu but a Smps, I will recommend the add of a filtering section.
personally, I Will go more for an external Psu (linear).

 

[TheSpeckySegg]

Yes you could but no need of the +48v.
As it’s not a linear Psu but a Smps, I will recommend the add of a filtering section.
personally, I Will go more for an external Psu (linear).

Do you have an recommendations for an external linear psu?

 

[oran.outan]

I don’t know any +/- 16v already build, But that should exist somewhere or almost in partial/full kit...
Maybe someone here will know !?

 

[oran.outan]

here you could get a pcb : Alimentation +16V -16V PCB seul
you have a BOM and can find everything on mouser...
for the transformer you could use a Triad VPT36-690.
you will have to had an IEC connector and a fuse.

 

[nsalis]

Acopian is known for their linear power supplies.

https://www.acopian.com/linear-regulated-power-supply-models.html
ns

 

[nsalis]

I just stumbled across this simple +/- 15 VDC regulated (= linear) power supply:

https://www.eiscolabs.com/products/epp02
They even have distributors in Canada, see:

https://www.eiscolabs.com/pages/distributors
ns

 

[JMan]

Acopian is known for their linear power supplies.

https://www.acopian.com/linear-regulated-power-supply-models.html
ns

I like a lot of the options they offer, but WOW those are expensive. In this case not worth it, IMHO.

I suggest just putting one of the many LM317/337-based DIY supplies, which are readily available from members such as volker, in an external box. You'd probably save $100 over some of these.