My GSSL - finally finished

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This would work also, I am sure but I have already finished my front panel design, metal work is in the process, all the elements and rotary switches are bought for the 8 GSSL units which I am building... I am sure it can be done with 1x12 rotary, too.

I am a very brave soul although some might say not so patient. Damn, I wish I had more DIY knowledge :green:
 
[quote author="Sammas"]I wonder how steffen's SC filter and the thrust filter would work in series?

So that the SC filter also effects what the thrust thingo is doing. Just thinking out loud... by the looks of it you could add a seperate 3 pole switch to choose between the Thrusts Loud, Med & then straight bypass back to the summing resistors... then another 6pole switch for the SC HPF.[/quote]

It should be a nice idea...
I planned two separate switches on the gssl i'm building, one for the thrust and one for steffen's sidechain filter... but i realized the the actual pcb's available is just the "LOUD section" so i decided to try to draw a pcb with both sections "MEDIUM and LOUD"...

I'm sure there is some errors, but consider that this is my first try... so any suggestion would be appreciated !


thurst_2.JPG
 
[quote author="Purusha"]Looks great, Neeno :thumb: hmm, I just wonder where is the second NE5532? Sorry for asking but aren't there suppose to be two?[/quote]

Thank you...

Why two 5532?
Isn't the 5532 a dual opamp ?
 
I did noticed two more things which you can probably explain. There are two 47pF next to your NE5532 but I see only one on the PDF schematics. And your 100nF on the left to the 5532 is probably a 100pF as mentioned in the PDF file.
 
:shock: This sidechain filter thingie elaborates alot!
Purusha, i'll take a look at the 1x12 rotary wiring later, just too tired. I already described the way to do it with a 3x12 before with good signal quality in mind, bypassing not needed sections, but thinking of the one deck possibly a kind of serial connection is best in the end...
hmmm.
later, sorry.

Good night.

Martin
 
[quote author="Purusha"]I did noticed two more things which you can probably explain. There are two 47pF next to your NE5532 but I see only one on the PDF schematics. And your 100nF on the left to the 5532 is probably a 100pF as mentioned in the PDF file.[/quote]

I am no expert either but I believe the lower 47pF should be the 100pF and the 100nF is connected to the pins providing the voltage to the NE5532. Should this not go to ground and not connect the +ve and -ve power supply?

Please chime in if im completely and utterly wrong.
 
[quote author="smallbutfine"]:shock: This sidechain filter thingie elaborates alot!
Purusha, i'll take a look at the 1x12 rotary wiring later, just too tired. I already described the way to do it with a 3x12 before with good signal quality in mind, bypassing not needed sections, but thinking of the one deck possibly a kind of serial connection is best in the end...
hmmm.
later, sorry.

Good night.

Martin[/quote]

Thanks Martin. Your help is much appreciated! :thumb:

If there is a chance to use the 1x12 rotary to accomodate both filters it would be the best for me, coz I already bought them. I was looking for 2x8 but couldn't find them. Hope to hear from you soon.
 
[quote author="Purusha"]Peter,

I guess you didn't have the time to look at my lousy drawings, yet :roll: :grin:[/quote]
I'm afraid the new postings notification stopped being sent out again, so hadn't seen the new stuff in this thread. I've printed your drawing, more on that later today.
 
Nice PCB-layout !

Please note though that the 'loud'-topology & -values are quite probably just like they've used originally; they're based on the patent.

The 'medium'-topology &-values are an equivalent circuit, so just something I knocked up that's realizing the same filter-transfer as in the 2500-manual.
'My circuit' for the medium-setting is probably not unlike they've done it, but not necessarily the same circuit.

FWIW...


Bye,

Peter
 
[quote author="Sammas"]I am no expert either but I believe the lower 47pF should be the 100pF and the 100nF is connected to the pins providing the voltage to the NE5532. Should this not go to ground and not connect the +ve and -ve power supply?

Please chime in if im completely and utterly wrong.[/quote]

I also think that the lower 47pF should be 100pF. I got also some explanation from a friend about the 100nF in the middle of two 47pF. It has something to do with blocking the noise...


I combined the Clintrubber's chematics with Neeno's picture for better view.

BTW. Neeno, what program did you use for the PCB layout? Is it posible to get the final layout for the PCB when it's tested?

API-Thrust%20layout.jpg
 
[quote author="Purusha"]I got also some explanation from a friend about the 100nF in the middle of two 47pF. It has something to do with blocking the noise...[/quote]

It's for decoupling of the 5532, in addition to the big decoupling caps of the supply (but these are a mile away). For stability reasons small caps often just, just as in.... the main-PCB of the G-SSL. :wink: It'd might not be really noticable, but you might indeed try using two of them, from each supply-pin to GND.


I also think that the lower 47pF should be 100pF.
Click to expand...

The 100p & 47p are not really critical - I just wanted to keep the product of the R_feedback & C_feedback somewhat alike. And everybody chooses that product (= where the -3dB-point is) a little differently, but in essence it's all about the same.
 
hey Purusha, I've been thinking about your question for a little while, and I don't think you can use a 1x12 switch to do what you want... but I think a 2x6 or a 2x12 will do the job.

Let me think about it a little more and I'll see if I can post a drawing for you.
 
[quote author="clintrubber"]The 100p & 47p are not really critical - I just wanted to keep the product of the R_feedback & C_feedback somewhat alike. And everybody chooses that product (= where the -3dB-point is) a little differently, but in essence it's all about the same.[/quote]

I am not such an expert in DIY so I was just following your schematics and comparing them to the PCB made by Neeno. Thanks for all explanations. Peter, what do you think about the 1x12, possible or not?

[quote author="Greg"]hey Purusha, I've been thinking about your question for a little while, and I don't think you can use a 1x12 switch to do what you want... but I think a 2x6 or a 2x12 will do the job.

Let me think about it a little more and I'll see if I can post a drawing for you.[/quote]

Thanks Greg. Man, I was again impatient and already bought 12 switches for 12 side-chain filters, I really hope 1x12 is possible otherwise I will have to go and beg the shop owner to exchange them for something else :?

Anyway, it's my bad karma. :wink: I guess I'll just wait and see if this is possible :thumb:
 
I'll draw what I had in mind last time I was soldering on that PCB.

Doing it all with a 1*12 rotary is possible, let's see if I'm still thinking that when I've finished drawing it.

Check back in a few hours, other stuff to do right now but will post this evening.

Bye,

Peter
 
[quote author="Purusha"]Peter, I can't wait to see your drawings :thumb: :grin: [/quote]

// edit: see next page for an update //

Here we are, the pic to show it's indeed overkill and the .pdf for full readability:

http://home.hetnet.nl/~chickennerdpig/FILES/API/API-Thrust-HPF-circuit_20060309.pdf

sc-circ_thrst_hpf_02.jpg


As in a previous thread, be sure to use an opamp for the leftmost one that can drive all this, so no TL072. Just stick to that 5532.

Skip the added HPF-frequencies if you like (see the notes in the drawing).


Have fun,

Peter
 
I saw that I hadn't exactly built it like originally drawn back then.

This update better reflects the circuit as on the veroboard-pic of a few pages back: a few additional trimmers and changed&added caps

Bye,

Peter
 

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