Racking Spectra Sonics 101

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Well the grounding is important, I've found it VERY tempremental on these cards.

I'm not famialer with the Triad's sicne I used an OEP, but I know that on the OEP I had ground the screen as well.

Cheers

Matt
 
Thanks Matta,
Since there is only +24 Rail.

On the JLM ac/dc you don't need the -24 Rail connected to anything.
What about the 0V rail on the Ac/dc... Goes to the GO BETWEEN and then to Ground (if Pin 1 and 3 are tied to ground)??

Except for + Basically everything goes to goes to ground in one way or another?
 
Hi David, i didn't racked my 101s yet, but one is wired inside a old case i use to check out stuff before rack it...

I'll suggest to remove the output transformer, and check it unbalanced.

If you are using the JLM psu, remember the the 0V on the JLM psu should be your star ground point. There is one of the fixing holes (the one near the 10R resistor) that shall be connected to your case, and then from the case you'll have a connection to your IEC.

I'll start from the input XLR:

- Input XLR Pin1 should be connected to the star ground (JLM PSU)
- Input XLR Pin2 and Pin3 should go to the GO BETWEEN input.
- Connect the 0V of your GO BETWEEN to the star ground
- Connect the transformer input to your GO BETWEEN output (i used 150:600)
- Connect the transformer ground to the star ground
- Connect the transformer output to your 101 input
- Connect the output of the spectrasonics to the output XLR and tie pin1 and pin3 togheter.

Hope this helps...

[quote author="cannikin"]Thanks Matta,
Since there is only +24 Rail.

On the JLM ac/dc you don't need the -24 Rail connected to anything.
What about the 0V rail on the Ac/dc... Goes to the GO BETWEEN and then to Ground (if Pin 1 and 3 are tied to ground)??

Except for + Basically everything goes to goes to ground in one way or another?[/quote]
 
Thanks Neeno and Everyone..

Ok.. I had to take a Break from this because I Blew up my JLM ac/dc by shorting the 48V rail... the LM317 Exploded and destroyed the PSU Traces

...Live and Learn....

Check it out Fellas... Finally Got it figured out!!! they sound great!

http://www.groupdiy.com/index.php?topic=184071#184071

Thanks So Much for everything
 
I just finished reading the patent about that 101 circuit (3,376,515) and since it's such a compact circuit & a bit different from the rest it'd be fun to thrown one on breadboard (one day...).

Is there a complete schematic with all component values out there ? Haven't found anything like that yet.

As I understood from the patent it's all Ge-transistors except for the two NPN output devices. Which types ? (not that I expect to be able to find those, but one has to start somewhere).


Regards,

Peter
 
[quote author="clintrubber"]I just finished reading the patent about that 101 circuit (3,376,515) and since it's such a compact circuit & a bit different from the rest it'd be fun to thrown one on breadboard (one day...).

Is there a complete schematic with all component values out there ? Haven't found anything like that yet.

As I understood from the patent it's all Ge-transistors except for the two NPN output devices. Which types ? (not that I expect to be able to find those, but one has to start somewhere).


Regards,

Peter[/quote]

edit: Ah, found the circuit-values, thanks Matt - I had already downloaded the schematic from the first page of this thread last week but hadn't really looked at it.
Everything's there :thumb:
 
[quote author="matta"]Hey Guys,

I've managed to get hold of the Spectra Sonics 101 Info/Sales Sheet (thanks to Doty)
and have it hosted up on my site. It has some great info and wiring advise, feel free to download it.[/quote]

In addition to the nice stuff that Matt found, I encountered a few more interesting downloads for 101-builders:

http://recforums.prosoundweb.com/index.php/mv/msg/9573/0/0/0/ (2 pages)

Especially:
http://www.technicalaudio.com/a2z/S/SpectraSonics/SpectraSonics_101_manual.pdf (courtesy of John Klett)

but have a look at the complete thread I'd say.

Regards,

Peter
 
Hey Clint

I have been working on some sub parts for the Diodes and Transistors.

Here is the thread:

http://www.groupdiy.com/index.php?topic=15506&highlight=101

I purchased the parts I listed in the first post and put them on the board... just haven't had time to hook to transformers and test
 
[quote author="cannikin"]Hey Clint

I have been working on some sub parts for the Diodes and Transistors.

Here is the thread:

http://www.groupdiy.com/index.php?topic=15506&highlight=101

I purchased the parts I listed in the first post and put them on the board... just haven't had time to hook to transformers and test[/quote]

Hi,

Yep, had seen that thread, thanks. Since the possible replacements weren't much easier to find here I'm settling for BC550 & BC560, with perhaps BC337 for the output-NPN's. Not completed yet, but I'll be reporting once done.

Bye,

Peter
 
More hello David,

As it happens I saw various differences in the component values of the previously posted schematic (earlier in this thread, 'the handdrawn one') and the one I linked to a few posts above here ('printed').

The differences concern various small differences in the resistor values, no big deal I expect; they're in essence the same, but sometimes jump to another close value in the resistorvalue-range.

But the cap in parallel with the 11k(10k7)-resistor connected to the collector of the first NPN Q1 differs more:
'handdrawn' vs 'printed': 20p vs 220p

It'll become clear from the breadboarding what the best value is, but in case someone with original 101-cards can have a look ?

Thanks,

Peter

Note I'm not involving the schematic-topology from the patent here, that one hasn't have component values and has a slightly different topology compared with the actual 101 - cards.

And w.r.t. 'printed' I mean the version on the last but one page of that pdf; as I understood the version on the very last page is some later suggested update or something. Are you still with me ?
 
[quote author="cannikin"]Its .002uf

Just measured it on the original board[/quote]

Thanks, but :shock:
It gets bigger by the minute !?! :? :shock: :wink:

You sure it's 2nF ? I mean, that's another ten times as much - on the first schematic I saw it was still 20pF and then 220pF.


Hey, you have original boards ? That's cool, convenient for some measurements when cloning :thumb:

Regards,

Peter
 
And FWIW here we have the 110, so with +/-24V supply for more headroom:
http://www.technicalaudio.com/a2z/S/SpectraSonics/SpectraSonics_110A_sch.pdf

So this is the card for which JLM gave the hookup-info earlier in this thread.
So when cloning it's easy to make either a 101 or 110, but I won't really be needing the higher levels possible with the 110. A joint use of +/-24V & 48V for phantom could be considered though.

Anyone toyed around with the 101 & 110 side by side by chance ?


There's some more SpectraSonics info there, thank you Mr. Klett:

http://www.technicalaudio.com/a2z/S/SpectraSonics/

Regards,

Peter
 
Yes this 110A circuit does have 2.7k input impedance so a 1:2 input transformer would work fine on the input to give 6dB more gain. Make sure you run it on the +/-24v as shown and only E & F go to 0v.
 
[quote author="JLM Audio"]Yes this 110A circuit does have 2.7k input impedance so a 1:2 input transformer would work fine on the input to give 6dB more gain. Make sure you run it on the +/-24v as shown and only E & F go to 0v.[/quote]
Thanks Joe for the confirmation :thumb: Yep, will use +/-24, thanks.

Since I'm cloning from scratch, it sounds like the 110A would be the best way to go - more freedom w.r.t. micpre-TX-configurations.

Since from what I read I got the impression that the 600 Ohm input impedance of the 101 & 110,
even when used with a 1:1 TX, give a bit too low inp.imp, correct ?
As in 'it will do just fine, but might have been a bit more'.

Regards,

Peter
 
Hey guys,

I'm racking my second pair of cards and wondering if there any way to stop the clicking sound when using a switch to change the feedback resistor?
 
Since from what I read I got the impression that the 600 Ohm input impedance of the 101 & 110,
even when used with a 1:1 TX, give a bit too low inp.imp, correct ?
As in 'it will do just fine, but might have been a bit more'.
I usually like the sound of most mics with 600ohm loads except ribbons.

I'm racking my second pair of cards and wondering if there any way to stop the clicking sound when using a switch to change the feedback resistor?
Try adding a 1000uF 16v cap in series with the gain resistors. There is no DC path made back to the feedback input which is the base of the input transistor so as long as this cap is big enough to keep the roll off point in the less then 5Hz point all should work fine and no clicks.

Do you use a ?Make Before Break? switch?
Either type of switch will make clicks as the DC level changes with each gain step when no cap is fitted. But adding the series cap should fix this as shown in the two circuits below.

SpectraSonics110Aasmicpre640.gif


The two ways to switch gain with a three position switch or centre off toggle will work with either card type.

SpectraSonics110asmicpre640.gif


If someone can try the cap on a existing build and see if the clicks stop and all works fine please post on this thread your findings as I have only been able to computer simulate the cap idea at the moment.
 
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