ASTROSIM (cab simulator)

[VoivoD]

https://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=53899&g2_serialNumber=2
https://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=53902&g2_serialNumber=2

Hey what is R12 here?

Also what pot types are on the main board? Linear or log?

[cab42]

Hey what is R12 here?

Also what pot types are on the main board? Linear or log?

The pots on the main board are both linear. The B is for linear. A is for audio or log. But check the schematic to be sure. The same goes for R12. I'm pretty sure its 100 ohms but check the schematic to be sure.  Just checked, its 100k.

BTW: The layout is not verified yet. I have a partly finished board on my table, that I hope to do something about in the near future.

If you start building,  I will advice you to check the layout against the schematic first. I did check the nodes, but I might have missed something.

[cab42]

Well, assumptions are the mother of all screw ups. I just checked my own build, and I have put in a 100 ohm for R12, probably assuming that the null prefix meant that there was none.

Never trust a layout on the internet, appearently not even your own.

Thanks Voivo, you saved me for a lot of debugging time.

[flc]

I breadboarded the circuit and wow...congratulation Deadastronaut on a brilliant design. It sounds excellent (even better than my amp+loadbox+Ir). I wish I had even a tenth of your knowledge and understanding of circuitry so I have a couple of questions that probably will demonstrate all my ignorance on the topic.
1) Can C4 C23 be substituted by a single 150n capacitor ? Same for C11 C13 (15n), if yes would it make much of a difference?
2) Is it possible to do mono in - stereo out (as in 2 mono out) ?
3) what about stereo in(2 mono in)- stereo out(2 mono out)

The reason for point 2 is that this way I could try and feed 2 different types of DI/preamp simultaneously before hitting the converters.
The reason for point 3 is for using a stereo reverb pedal before the Astrocab rather than after 

I do apologies if these are silly questions so feel free to ignore them if they are
Once again ...great design 

[deadastronaut]

no such thing as silly questions here...


hi, yes the caps substitutes will be fine...

to do stereo you may as well build 2 astro cab sims...(maybe in one unit)

then you have the best of all options your after....

cheers man, rob. 

[flc]

Thank you Rob, much appreciated...and thank you also for the welcoming (that was my first post on the forum)

[cab42]

Last week I finally finished my vero build, and it actually works! However, I need to spend some more quality time with it before I will call it 100% verified.

I had some issues, but they were all related to sloppy soldering and a bad switch (and a trace cut in a wrong spot, but we don't talk about that).

One thing puzzles me. I have just above 9V on the V+ on the board, but my Vref as well as pin 1-3 and 5-7 on the IC is around 5.5V. I would have expected them to be around 4.5V. I have checked the resistors on the voltage divider, and they look fine. Is that a problem?

But it seems to work as expected. It sounds great through headphones, either on its own or together with a sub mini tube preamp. I haven't tried the line out yet.

During the debugging I checked the layout at least 10 times  and I am pretty confident that it is correct.

I did one thing different in the build compared to the layout. Instead of making the double link under the IC, I ran the jumper directly from P8 to C8, moved R5 one column to the right, and placed a jumper from P2 to L2.

I will probably try to incorporate a volume control for the headphones and an aux input. There are some suggestions in the previous pages for that.

Now I need a big box! Maybe even with room for a tube preamp.

[deadastronaut]

Oh by the way guys i had some 1590b small sized pcbs made

Of just the cab sim part...no phones/xlr , handy for an easy cab sim build..

Verified. 

https://deadastronaut.wixsite.com/effects/astrosimcabsimulator

[VoivoD]

Where is R14 and R15 on the schematic?

[deadastronaut]

The unknown knows... 

At the modern, vintage switch..

[cab42]

Where is R14 and R15 on the schematic?

Run a wire from B1 on the vero to the middle lug of the V/M-switch. Solder R14 to one of the outer pins and R15 to the other and solder the other ends of the resistors together. Connect this junction to lug 1 on the air pot. Something like this:



Hope that helps.

[VoivoD]

Abandoned since I will do everything digital. Sorry for not replying to pm, but it asks me too many questions and could get past them with correct answers.

[Marcseo]

Hi, I recently bought two of these PCBs via Musikding. Both PBCs are labeled as 2018 V2, although all the documentation I have seen is previous to this version. Also, both PCBs are missing all the tags/names for all the cabling (so no 9v, ground markings, etc). Should I take any special considerations or i can just go with the old documentation and assume all the connections are the same?

Thankss

[deadastronaut]

Hi, I recently bought two of these PCBs via Musikding. Both PBCs are labeled as 2018 V2, although all the documentation I have seen is previous to this version. Also, both PCBs are missing all the tags/names for all the cabling (so no 9v, ground markings, etc). Should I take any special considerations or i can just go with the old documentation and assume all the connections are the same?

Thankss

use the document pdf for labelling. and they will be fine.

rob.