Soundskulptor STS stereo tape simulator

[baadc0de]

Cool,

it seems I'm not the only one overwhelmed with non-diy stuff

the tone control I get in theory (but I will draw down a diagram and post it here when I can). the limit one, I'm not so sure about..

 

[baadc0de]

I've added the "diode off" and "diode off + modern lpf filter" to a switch on the STS and they're praised very much for vocals around here because of that. I'll ask a real mastering engineer to borrow my unit for a few days and we'll see what he thinks.

 

[baadc0de]

I've added the "diode off" and "diode off + modern lpf filter" to a switch on the STS and they're praised very much for vocals around here because of that. I'll ask a real mastering engineer to borrow my unit for a few days and we'll see what he thinks.

Do You use the same value as Tubefreak do? If You don'mind, would You like to give the schematic of the mod please...

Thank You.

Yes, the same values as tubefreak, however I only did 2 mods not a lot more that he suggests. I'll be building one soon with all of his mods, just organized a bit differently. We'll see how people will react to that one, but I'm getting raving comments for the stock unit with this:

My mod is a three way two pole switch, on-off-on operating from left to center to right. The left side of the switch controls the D1 leg that would go to ground. In the fully left position it connects D1 leg to ground, center and right positions break this connection.

The right side of the switch connect a resistor 45R from crosspoint R38/R39 to R40.

This way, on the left position, the unit is stock, on center diode limiting is off and on the right position the limiter is off + lpf filter is less aggressive and there is more gain.

 

[baadc0de]

@baadcode:

Cool, do You experiment with other R value for the LPF? And do You change the R42 per Tubefreak info (1k6)?

Thank You for sharing the information dude.

Cheers.......

No problems man, that's what this forum is all about

I didn't change the R though and neither did I change R42. We all liked it just the way it was so much and I had 8 channels to mod in one evening before a "DIY gear vs UAD plug-ins shootout" so I did my best on that.

The hardware STS trumped the plugins I was told. Now everyone wants one.

 

[baadc0de]

I don't recall really since I'm not the audio engineer type - I just make things and then others tell me if it's OK or not. I do know people love it to spice up samples or keyboards and most of that is in stereo so I guess it does good work there at least partially.

That said, if you want to PM me your email and I'll send you a before/after mp3 that I did with a dance song where I dropped it through my (stereo) pultec, altec 436 and STS. I think that's all I tried or have results of on hand. You could also send me some material on FTP or something and I could bounce it through my build at various settings if that would help you.

 

[baadc0de]

Hey all..

could you take a look at this. I'm not sure I mapped out this as it should be.. tubefreak, if you have google docs, I'll send you edit rights:
https://docs.google.com/spreadsheet/ccc?key=0At6CHuIO8EcMdHN2Y1U5TGVFMFRJenREa0xLNmFSeXc

Cheers,
Bojan.

Imo the stock sound of the in/out opamps are fine. I added the transformers to the whole unit without removing any of the other parts. If I would start from scratch, then this would certainly be an option. But I doubt how much difference it will make, it's a colour box after all.

In my unit for each channel I'm gonna make two rotary switches and an on/off for the low pass.
voicing = 9 steps, 3 decks
limiter (=diode) = 5 steps, 2 decks
low pass = SPDT

The voicing switch:
Deck one - Coil H1
1. H1 coil not connected
2. H1 coil connected to ground through an 24R resistor (less bass cut)
3. H1 coil connected to ground (linear saturation)

Deck two resistor R30
1. not connected
2. 120R
3. 200R (less treble cut in 7.5 ips)
4. 120R + 200R parallel
5. 4R (less bass cut in 30 ips)

Deck three negative feedback
1. off
2. 75KR between TP3 and D1

total voicings
1. 7.5 ips (bass boost, high cut)
2. 7.5 ips + 200R (bass boost, flat high)
3. 7.5 ips + H1+24R + 4R (slight bass boost, flat high)
4. 7.5 ips + H1+24R (slight bass cut, slight high boost)
5. 30 ips (bass cut)
6. 30 ips + 4R (flat !!!!!)
7. 15 ips (smile EQ)
8. 7.5 ips with 75K between TP3 and D1 (smile curve)
9. 15 ips + 200R (high boost)

Limiter:
1. D1+D2 off (for no diode clipping = more coil compression and more open sound)
2. D1 on with 2k2 resistor to ground (for assym. soft clipping)
3. D1 to ground (for assym clipping)
4. D1+D2 on with 2k2 resistor to ground (for symm soft clipping)
5. D1+D2 on (for sym clipping) (=stock)

On any stock STS you can cut the leg of the diode D1 and add a switch in between.

low pass switch
1. stock
2. 45R from crosspoint R38/R39 to R40.
this changes the low pass filter, but also adds loads of gain and gives it a more 'modern' overall voicing. Maybe I'll pair this with a change for resistor R42. At 1k6 it offers more gain, which could be a good setting for the stock low pass filter.


Maarten

 

[millzners]

Man this project is so tempting, every time it comes up to the top of the heap I spend an hour going over it trying to decide and tonight is no different.  If it weren't for the VAT I'd probably be all over it.

 

[Neily]

Man this project is so tempting, every time it comes up to the top of the heap I spend an hour going over it trying to decide and tonight is no different.  If it weren't for the VAT I'd probably be all over it.

Seriously. Buy one! You will not regret it!! I am so happy with mine. I can't even begin to explain how much it rules... Very easy and nice kit with great instructions.... Sounds amazing... They even sent me candy! Cost me something like $600 (usd/cad) after shipping to Canada for the full kit.

 

[slowbass]

I also like mine very much : it was a clean and easy build with the kit (no wires which are often boring for me !) A lot of info (even an instruction CD, sweets...) The sound is cool too (to be true, at the beginning, it took me a while to perceive its action.).
Applying it on stereo source can be a bit tricky to get the right balance (the two chanels are independant) : first I tried to send a mono signal and inverted the phase of one chanel to cancel the sts but now, I do it roughly by ear + the volume meter and it's ok

I would have like one power switch.

 

[baadc0de]

Bumpity bump bump.. did anyone take a look at the switch arrangement and could verify my reasoning about it?

Hey all..

could you take a look at this. I'm not sure I mapped out this as it should be.. tubefreak, if you have google docs, I'll send you edit rights:
https://docs.google.com/spreadsheet/ccc?key=0At6CHuIO8EcMdHN2Y1U5TGVFMFRJenREa0xLNmFSeXc

Cheers,
Bojan.

Imo the stock sound of the in/out opamps are fine. I added the transformers to the whole unit without removing any of the other parts. If I would start from scratch, then this would certainly be an option. But I doubt how much difference it will make, it's a colour box after all.

In my unit for each channel I'm gonna make two rotary switches and an on/off for the low pass.
voicing = 9 steps, 3 decks
limiter (=diode) = 5 steps, 2 decks
low pass = SPDT

The voicing switch:
Deck one - Coil H1
1. H1 coil not connected
2. H1 coil connected to ground through an 24R resistor (less bass cut)
3. H1 coil connected to ground (linear saturation)

Deck two resistor R30
1. not connected
2. 120R
3. 200R (less treble cut in 7.5 ips)
4. 120R + 200R parallel
5. 4R (less bass cut in 30 ips)

Deck three negative feedback
1. off
2. 75KR between TP3 and D1

total voicings
1. 7.5 ips (bass boost, high cut)
2. 7.5 ips + 200R (bass boost, flat high)
3. 7.5 ips + H1+24R + 4R (slight bass boost, flat high)
4. 7.5 ips + H1+24R (slight bass cut, slight high boost)
5. 30 ips (bass cut)
6. 30 ips + 4R (flat !!!!!)
7. 15 ips (smile EQ)
8. 7.5 ips with 75K between TP3 and D1 (smile curve)
9. 15 ips + 200R (high boost)

Limiter:
1. D1+D2 off (for no diode clipping = more coil compression and more open sound)
2. D1 on with 2k2 resistor to ground (for assym. soft clipping)
3. D1 to ground (for assym clipping)
4. D1+D2 on with 2k2 resistor to ground (for symm soft clipping)
5. D1+D2 on (for sym clipping) (=stock)

On any stock STS you can cut the leg of the diode D1 and add a switch in between.

low pass switch
1. stock
2. 45R from crosspoint R38/R39 to R40.
this changes the low pass filter, but also adds loads of gain and gives it a more 'modern' overall voicing. Maybe I'll pair this with a change for resistor R42. At 1k6 it offers more gain, which could be a good setting for the stock low pass filter.


Maarten

 

[baadc0de]

There you go, attempt mkII  ;D  8) 

 

[Hank Dussen]

Verrrry nice!

 

[Gilgamesh]

There you go, attempt mkII  ;D  8) 

Been monitoring this thread for a while.

This has all the mods suggested by tubefreak above? Very interested to hear your thoughts on the sound. Looks freaking great!

 

[baadc0de]

There you go, attempt mkII  ;D  8) 

Been monitoring this thread for a while.

This has all the mods suggested by tubefreak above? Very interested to hear your thoughts on the sound. Looks freaking great!

Hey..

yeah, it has the voicing mod and a part of the limiter mod implemented (just the fully on, fully off and d1+2k2 -- soft assym). I have added some additional settings to it so that I wouldn't need to stop the rotary switch. I need to debug it a bit or at least verify that I'm doing it correctly because some settings have massive distortion and gain. Overall though, both limit and voicing switches are good investments.

Cheers!

 

[baadc0de]

This is the documentation for the mods.. it might change somewhat if we find any errors or if there would be more information required.

http://distopiksound.com/Tape%20Simulator%20Mods.pdf

Cheers,
baadc0de.

EDIT: updated with reference table at the end for the switch.

 

[whomper]

Reviving this topic....

I have built my STS using Purusha case and the mods stated above (mods are a must, both 12 state selector and soft limit, they adds many possibilities to sculptor the sound). A great build. Mods where straitforward and JPK's support was just perfect.

Best of all, the sound quality is awesome. Adds that little touch to my masters.

 

[whomper]

Hi guys!

As I was mainly focused around 15ips, I did not pay enough attention to the 7.5ips modes. Now that I did, both 7C and 7D sound strange. 7D especially sound low and mute although it should have a treble boost according to the mod table.

Another guy (peskado) had stumbled into the same issue. We both traced the switch according to the mod build spec and all look legit.

How do the two modes (7C and 7D) work for others?

 

[marcourageous]

Hi guys!

I've just ordered the STS mini kit and the case from Purusha cases too, and this is going to be my first ever DIY project.
I was wondering if  anybody care to comment on what Whomper said earlier about 7C and &D?

Thanks!

 

[Pignouf]

Hey guys, another owner of a STS here.

I tried to mod it, but I've got a problem here. Right channel works as it should, but the left channel cuts out when on positions 7.5E, 15C , 30B/D. According to the voicing table, what's common about those positions is the mid wafer going to R21/D1 through a 75 Ohm resistor. I already measured the connection between the switch/resistor/PCB R21 and those are OK... Anyone got an idea where the problem could be? Any help would be appreciated.

Thanks

 

[Pignouf]

I managed to find my problem, as usual it was a "duh" moment (75 Ohm instead of kOhms, worst is I even perpetuated the mistake in my previous post it seems, I think I have a good reason to buy a smoke extractor now ), but I seem to have a problem at positions 7C and 7D as stated before in this thread, on both sides.

Hi guys!

As I was mainly focused around 15ips, I did not pay enough attention to the 7.5ips modes. Now that I did, both 7C and 7D sound strange. 7D especially sound low and mute although it should have a treble boost according to the mod table.

Another guy (peskado) had stumbled into the same issue. We both traced the switch according to the mod build spec and all look legit.

How do the two modes (7C and 7D) work for others?

Indeed, lower volume and muffled sounding (although I believe the volume is a result of the massive HF loss), worst is 7D. Everything matches up according to the mod build. I traced a frequency plot with Fuzzmeasure, and found that position 7C ends up roughly as a -3dB/octave slope, and 7D shows up as a textbook -6dB/octave slope. Cutoff at about 50 Hz for both...

So it seems I'm the third person encountering this problem. Might there be some mistake in the mod instructions?

Thanks