Multicab SIM..my own design cabinet simulator .. it works!! cool!

[DougH]

The phase-shift I mentioned is a little more complicated than Doug makes it out.

You're right Mark. And something kept bugging me about this in my subconscious- that is, there's a frequency dependent component in the amt of phase shift in a standard guitar "phase shifter" circuit. But when I remember my Bad Stone, I think my view turned more towards the "comb filter" effect I remembered. I think that would still be useful for replicating some of what happens with a multi speaker cabinet. But a BBD or some other non-freq-dependent scheme might be better for imparting "spatiality". (But in that case, for me, I'd just use an existing delay or reverb.) Then again, it may not make much difference, as Daniel has suggested, given the way we hear bass vs. treble. The only way to know for sure is to experiment.

[frequencycentral]

Very nice work on the finshed enclosure Daniel, I really like the graphic too.

Excellent work Daniel - it looks pretty simple yet flexible. Yes?

When I recover from my submini tube fetish I'll gives this a go...........

I was also theorizing that this could be a nice addition to the Valve Caster.  I really like how the Valvie works with my amp sim.  It could make a nice all in one package.  I may just have to bread board this too! 

It occurs to me that it would be entirely possible to re-enginner this circuit replacing the two unity gain buffer opamps with a dual triode. So - instead of using a Valvecaster added to Daniel's 'Multicab Sim' you would have a 'Tube Multicab Sim'. I guess it would also be possible to replace the 2N3904 with a triode stage too. Using two dual triodes, this would leave a spare triode which could be used to overdrive the front end. I don't know how differently low voltage triodes would affect the frequency response as oppossed to the solid state version's frequency response. But it would certainly be interesting to find out. I'll put this idea on my 'things to try out with submini tubes' list - if Daniel has no objection to his circuit being hacked!

[Mark Hammer]

Although the flat-response phase-shift IS a little more complicated than Doug originally proposed, Daniel's comments got me thinking.  Maybe the flatness is not all that critical.  Considering how omni-directional the low end is (the very reason why 2.1 and 5.1 systems can exist - you only need one subwoofer), maybe adding some amount of phase shift across everything from, say, 300hz on up is enough to do the job.  Realistically, if you had one open back cab with 4x10s, and one closed back cab with 4x12s, and you were standing about 8ft in front of them, exactly what aspects of their individual qualities would your ears be drawn to?  Certainly there would be no harmonic content differences in that zone below 300hz.

So, maybe nothing particularly fancy IS required, and everything I described in my earlier note is mere theory-driven overkill.

[dschwartz]

here is a .rar file with the result of my pseudo stereo generator:
http://diynoise.googlepages.com/pseudostereo.rar

there are 2 audio files.. clean.wav, wich i downloaded from the web for testing with ltspice (i´m at the office now  )

and output2.wav..wich has the clean signal on one channel and  the effected signal on the other (i don´t know wich is wich)..

play the files one after the other to percieve the difference.. output.wav is clearly stereo!

[DougH]

Sounds cool! I love it!

I'm going to have to try this...

[dschwartz]

Very nice work on the finshed enclosure Daniel, I really like the graphic too.

Excellent work Daniel - it looks pretty simple yet flexible. Yes?

When I recover from my submini tube fetish I'll gives this a go...........

I was also theorizing that this could be a nice addition to the Valve Caster.  I really like how the Valvie works with my amp sim.  It could make a nice all in one package.  I may just have to bread board this too! 

It occurs to me that it would be entirely possible to re-enginner this circuit replacing the two unity gain buffer opamps with a dual triode. So - instead of using a Valvecaster added to Daniel's 'Multicab Sim' you would have a 'Tube Multicab Sim'. I guess it would also be possible to replace the 2N3904 with a triode stage too. Using two dual triodes, this would leave a spare triode which could be used to overdrive the front end. I don't know how differently low voltage triodes would affect the frequency response as oppossed to the solid state version's frequency response. But it would certainly be interesting to find out. I'll put this idea on my 'things to try out with submini tubes' list - if Daniel has no objection to his circuit being hacked!

i´m not sure if the sallen key filters would be as efficient with tubes as they are with opamps..
If i were a tube-maniac i´d  stick with the opamp filters and replace the first bjt section with a triode.. the other triode i´d put it in the front as a boost, in order to get some "tubish" saturation/compression..maybe i´d study power amp distortion to emulate  that (well, i mean TRY) with the triodes cascade..

i would not be offended if you hack my design, as long as you mention me as the original designer (as i mention ROG for inspiration and some ideas)

[audioguy]

I have attempted a perf layout for this circuit, which I think is more than interesting.............next one in my to-build list

http://www.aronnelson.com/gallery/main.php/v/Xaviers-shrine-of-noise/Layouts/Policab+simulator.gif.html

Please let me know if you find any error. i have used 2x single opamps, I guess it should work, otherwise please correct me

Have you verified this one yet???

[dschwartz]

I have attempted a perf layout for this circuit, which I think is more than interesting.............next one in my to-build list

http://www.aronnelson.com/gallery/main.php/v/Xaviers-shrine-of-noise/Layouts/Policab+simulator.gif.html

Please let me know if you find any error. i have used 2x single opamps, I guess it should work, otherwise please correct me

Have you verified this one yet???

no, it has some errors..

[audioguy]

Bummer... I wanted to give it a shot

[alfafalfa]

Daniel ,


Your speaker sim sounds very good but you say it still has errors. Have you solved this because you recommend it ?

And do you have a pcb for it ?

Alf

[dschwartz]

the perf layout above has errors..not the schematic

[alfafalfa]

Okay . that's clear so  I'll design my own pcb.

Thanks,  Alf

[deadspeaker]

I have a board etched a drilled. I'm really excited about building this one. Are there default settings for certain popular speaker cabs?

[Brymus]

The schematic for the bass version is not showing up ,
Daniel would you mind reloading it or sending it to me ?
This does sound really good IMO.definetly worth trying out.

[deadastronaut]

yeah nice aroud 0.50...

love a scoop tho..............good stuff!..

[bside2234]

I too am interested in the Bass version which isn't showing up. Also the all pass pseudo stereo schematic isn't showing up either.
Anyone have these they can repost?

[miwanone]

I don't know if there is any interest in this, but I made a pcb for this (unverified but it should work) and I thought someone might want to use it. I put it on my website, it's a .zip with a layout, pcb, schematic and partslist.

[alex.myro3]

i am inderested to build this cab sim.can you post the schematic or layout from your final edition,with stereo feel.

[MarsSound]

my first post!

I really like to build this nice sounding cab-sim (the guy from Chili, Daniel?, builds more nice thinks!) and use it not only for guitar but also for bass guitar.
So, I want to use switches to change the initial frequencies to different settings.

I can solder and build things but I don't know how they works.
Can somebody please help me with this?

to change the bottom frequency do I have to change C11?
or also C7?

to change the top frequency do I have to change C4?
or also C3?

to change the mid-scoop do I have to change C9?
or also C6? I was thinking both....

how does it works? changing to lower condenser-values also lower the frequency?
and higher changes the frequencies up?

And what are good starting-values to change the condensers?


I appreciate all sort of help and thanks!

[MarsSound]

here's an alternative schematic I made. double-checked: