Any cab simulator circuit worth building?

[Rob Strand]

Choosing a cab is a personal preference so it's hard to give any advice.

Indeed.

I did this experiment:
- Get sounds clips from a good sounding speaker sim which gives both the sim and non-sim output.
- Feed the non-sim output in another speaker sim that sounds good.   

Obviously the results are quite different.  The interesting thing is it often doesn't sound that great.   I am very suspicious the amp settings are tweaked for good sound on one sim and they wouldn't be the amp settings used for the other sim.    To some degree amp eq can tweak the EQ to compensate for the the speaker sim.

A recording from a mic'd 4x12 wasn't too far off the V30 cabsim, which was recommended in this thread.  Perhaps a knock the lows down a bit.  It can be tweaked somewhat but you could do a lot worse.   Compared to the Lart and Val sims the V30 sim sounds a bit muddy for metal.

https://www.diystompboxes.com/smfforum/index.php?topic=70445.0

The ability to vary the high-end seems very desirable because it can adjust for people's preferences.
Adjustable low end seems worthwhle as well maybe a switch would do.

[temol]

Obviously the results are quite different.  The interesting thing is it often doesn't sound that great.   I am very suspicious the amp settings are tweaked for good sound on one sim and they wouldn't be the amp settings used for the other sim.    To some degree amp eq can tweak the EQ to compensate for the the speaker sim.

Exactly. Given sim can shine with one amp/preamp but with the other amp it might be just average

T.

[jhsa]

I am not into metal I do use some good overdrive though.. I also like some light(er) distortion/overdrive. Not into fuzz.
I like a really good clean sound out of my Fender Strat. I play several different types of music.
What I am looking for is just taking that distortion fizz away when directly plugged to the mixer through my pedals or pedalboard.
I am building the stock Simple Cabsim as i type this, and will try to still test it tonight without waking my neighbors up

João

[jhsa]

Guys, it seems that at least the Simple Cabsim is working, but it is not doing what I expected (or was hoping ) it to do
It seems there is still a lot of fizz with the distortion.. i gotta say that it seems it improved the clean sound. I did 2 recordings but I can't upload them to the forum. is it possible to add mp3 files somehow? Or can we only add images?
Te first recording was without the Cabsim, and the second with it. The mixer's channel EQ was bypassed.
Shame that i can't upload the files

joão

[J0K3RX]

jhsa - You really need some sort of preamp in your signal chain... It should be somewhere before the cab/speaker sim before you run into the channel on the mixing console. It is also important where you connect the other pedals in the signal chain. Like if you use delay, chorus or reverb you may want to insert them between the preamp and cab sim or after the cab sim or maybe better to run them into the effects send/return on the channel of the mixing console. Other pedals like overdrive should be before the preamp etc.. In any case, you should get a preamp because the cab sim alone is not a preamp. It's just a filter that has been designed to shape the signal coming from a guitar preamp and make it sound somewhat like a complete guitar amp and cab being mic'd up. As was said earlier, the cab sim may sound vastly different depending on what preamp you throw in front of it and I am fairly certain that it's gonna sound like a sh!tty mess without any preamp at all... 

[J0K3RX]

I did 2 recordings but I can't upload them to the forum. is it possible to add mp3 files somehow? Or can we only add images?
Te first recording was without the Cabsim, and the second with it. The mixer's channel EQ was bypassed.
Shame that i can't upload the files

joão

You can upload the files. You just can't upload them directly to the forum 

You have to upload them to a file hosting site of your choice and then post a link here in the forum.

[Rob Strand]

Simple Cabsim

The Lart V2 simple cab sim lets through quite a bit more highs than say the V30 sim.
This is where preference can come in.   It's possible to remove some highs by
modifying the filters, especially the last stage.  However I'm reluctant to suggest ad-hoc
mods and create yet another speaker sim.

[jhsa]

jhsa - You really need some sort of preamp in your signal chain...

I thought of that, and thank you for the confirmation. I did try a Valvecaster circuit between the last pedal and the cabsim and it seems to get a bit better as far as fizz was concerned.

It is also important where you connect the other pedals in the signal chain. Like if you use delay, chorus or reverb you may want to insert them between the preamp and cab sim or after the cab sim or maybe better to run them into the effects send/return on the channel of the mixing console. Other pedals like overdrive should be before the preamp etc..

To test this I have a compressor, then a OD and then a delay just before the cabsim. then straight into the mixer.
My mixer doesn't have channel " Effect Inserts". It is a little SC Ui12 digital mixer. Love it to bits by the way but that is for another topic

In any case, you should get a preamp because the cab sim alone is not a preamp. It's just a filter that has been designed to shape the signal coming from a guitar preamp and make it sound somewhat like a complete guitar amp and cab being mic'd up. As was said earlier, the cab sim may sound vastly different depending on what preamp you throw in front of it and I am fairly certain that it's gonna sound like a sh!tty mess without any preamp at all... 

Understood
Any good DIY preamp I should try?

Thank you

João

P.S. - Forgot to say. When I perform, I use my BOSS pedalboard most of the time. What I am trying to do is to have an alternative setup that is completely built my myself. I have been messing with electronics since a few years and I love to build my own stuff. That goes also to my radio control Airplanes hobby. I build radios, receivers, sensors, etc. So many cool projects and very little time

[jhsa]

Simple Cabsim

The Lart V2 simple cab sim lets through quite a bit more highs than say the V30 sim.
This is where preference can come in.   It's possible to remove some highs by
modifying the filters, especially the last stage.  However I'm reluctant to suggest ad-hoc
mods and create yet another speaker sim.

as Temol mentioned in a post somewhere above, the simple cabsim can be modded to output less highs. It is a mod by Bajaman..
I will try building this after. I don't have any 39nF caps and 560pF caps. So, i will need to parallel some but this will make it huge

One thing I wanted to do with the Simple CabSim if it works good for me, is to build a simple DI Box circuit and put it in the same enclosure, probably on the same board. I was thinking about something like this single FET DI Box.

http://tataylino.com/simple-di-box/


João

[J0K3RX]

Not really sure with that mixer you're using.. It has a hi-z input and it looks like you can enable/disable it in the digitech interface. You could try to diy padded xlr cable or you could build a di box I guess but, it seems like you could get a good or at least acceptable sound with what you have. I had a digitech rp1000 and I sorta liked the amp and cab models and the clean sounds were really good. Compared to other digital modeling processors it had a more realistic tone and feel unlike Line6 garbage which I absolutely hate! Maybe try to diy a h&k redbox and kill 2 birds with one stone. I have and they really sound pretty good.. The new redbox 5 looks great but I haven't seen any schematics floating around, yet.

[jhsa]

Not really sure with that mixer you're using.. It has a hi-z input and it looks like you can enable/disable it in the digitech interface. You could try to diy padded xlr cable or you could build a di box I guess but, it seems like you could get a good or at least acceptable sound with what you have. I had a digitech rp1000 and I sorta liked the amp and cab models and the clean sounds were really good. Compared to other digital modeling processors it had a more realistic tone and feel unlike Line6 garbage which I absolutely hate! Maybe try to diy a h&k redbox and kill 2 birds with one stone. I have and they really sound pretty good.. The new redbox 5 looks great but I haven't seen any schematics floating around, yet.

have an original RedBox MKIII (Quite old) and the output signal is weaker then the input. It also does not remove that fizzy sound when using overdrive. I also built 2 other Di Boxes already.
About the RedBox, I have the feeling that at least the one I own is not very well designed, specially the output stage where they have 6K8 resistors on the output and 470 Ohm resistors to get the phantom power.. I think they are swapped?? First i thought it was a flay on the DIY design, but then I have measured the original and it is really like that. I was going to build one but decided not to, and went for the ESP design instead. 
I also saw a very simple DY circuit yesterday (picture attached), and thought that I could try it at the output of the simple CabSim, and even build it on the same board


I just need to build a good clean preamp to be connected before the Simple CabSim...

João

[Rob Strand]

ave an original RedBox MKIII (Quite old)  ... It also does not remove that fizzy sound when using overdrive.

My understanding is the RedBox MKIII is similar to the Redbox Classic.   The Redbox Classic lets a bit more highs through than some. Probably around the same zone as the Lart 2.0 simple cabsim.

The bajaman mods might help however this one does still let some upper top-end get through.
After that try the V30 sim or the Marshall JTM.

If you had a variable high-freq control you can dial in the amount of fizz.

[jhsa]

My understanding is the RedBox MKIII is similar to the Redbox Classic.

It is   

The bajaman mods might help however this one does still let some upper top-end get through.
After that try the V30 sim or the Marshall JTM.

I will also build another Simple Cabsim with the bajaman mod. For the moment I am testing the original version. I can't say that I am disappointed, far from it, but still didn't use it enough to say that I like it

If you had a variable high-freq control you can dial in the amount of fizz.

The problem is not just dial in the amount of fizz, it is doing it without hurting the  overall sound   
I have been busy building this today




Then I connected the Simple CabSim between this preamp and my mixer. Channel EQ on the mixer was bypassed. I did like it. The amount of fizz on the speakers was acceptable. I can probably use the mixer's parametric EQ to get rid of it completely. The problem was the recording and my in ear monitor. On the monitor it was terrible, lots of fizz. but still, it was an improvement. The clean sound was quite good, for my taste of course


João

[jhsa]

Hey Guys, would the simple CabSim be happy at about 15V?

Thanks

[J0K3RX]

Hey Guys, would the simple CabSim be happy at about 15V?

Thanks

Yes, as long as your caps are rated at or above 15V.

[jhsa]

Great, thank you..
When I built it, I left space on the veroboard to add this simple balanced driver circuit.
Added another 4,7K between the cabsim's 1uF output capacitor and the balanced driver circuit.
it does seem to work well and no need for a DI Box

João

[Willypp]

Just going to say that I've put Lart's simple sim on vero in my DI, and I'm loving it tbh.  This thing has a klon buffer, sonic stomp, lart's simple cabsim, and TH's Line Driver driving an XLR output and 1/4 unbalanced out (as well as an uneffected 1/4 out after the buffer).

[deadastronaut]

nice...

[sixthfloor]

What about bass cab sims ? Are there any schematics around ?

[jhsa]

Very good job in there

Yeah, the simple CabSim does a wonderful job. I used a 1 transistor Balanced driver though, and it works really well.. Keep it simple  

João