Liquitone Deluxe Tremolo/Liquitrem Project

[Liquitone]

This is a tremolo designed around using the building-blocks of the Uni-Vibe with added circuitry to take you from standard tremolo to harmonic/filter modulated sounds.
I entered this design in the 10-year anniversary contest and promised to create this post.
I would like to thank Kaycee for having a go at building one and pointing out some mistakes in the schematics/layout.

The idea started when I wanted to build a tremolo that sounded somewhat like a Fender Blackface amp or a Rhodes piano tremolo,
and I figured using a lamp/photocell would be the best way to achieve that. I wanted it to have simple controls and no need for extreme choppy sounds.
I really liked the sound of the Uni-Vibes amp-stages and decided to use these for my tremolo.
This first version only had speed and intensity knobs, but after reading about this thing called harmonic tremolo I decided to expand the circuit by adding harmonic modes.
After tinkering around a bit I found it didn't really sound like a harmonic tremolo, like Jon Patton's Cardinal Tremolo (which was the inspiration for these experiments),
but instead of trying to get closer to these sounds I went into the opposite direction. I shut myself off from any outside information and just tried finding sounds I liked,
wrote down how I got them and put them under a 4-way switch.
Mode 1 is standard amplitude modulated tremolo.
Mode 2 somewhat resembles harmonic tremolo, with frequency modulation along with amplitude modulation.
Mode 3 has little amplitude modulation but strong frequency modulation, somewhat resembling a Uni-Vibe's chorus setting.
Mode 4 is a subtle frequency modulation giving pitch vibrato sounds.

I have added turret layouts for those who want to have a go at that, so this thread may also serve as a mini-turret layout tutorial of some sort.



R1,R11,R19        -22K
R2                     -2M2
R3,R5                -1M2
R4,R17              -6K8
R6,R10,R12       -47K
R7,R23,R28       -4K7
R8,R26,R27       - 68K
R9,R14,R29,R30- 100K
R13                  - 220K
R15                  - 1K2
R16,R21            - 3K3
R18                  - 3K9
R20                  - 10K
R22                  - 1M
R24,R25            - 1K
R31,R32            - 100R
R33                  - photocell

TR1 - 5K
TR2 - 100k
TR3 - 1k

C1,C3,C4,C5,C6          - 1uF Film
C2                             - 330pF
C7                             - 0.1uF Film
C8                             - 0.22uF Film
C9                             - 0.33uF Film
C10,C11,C12,C13,C14 - 1uF Elco/Tantalum
C15,C16                     - 10uF Elco/Tantalum
C17                           - 0.1 Film
C18                           - 1000uF Elco

D1,D2 - 1n914
D3 - bi-color common cathode LED
D4 - 1N4001

Q1 - 109C or other general purpose NPN sil.
Q2,Q3,Q4 - BC109B/2SC828/2N3904 or other general purpose NPN sil.
Q5,Q6 - MPSA13 or other general purpose NPN sil darlington.
Q7,Q8 - LM7812/18/24 voltage regulator

Lamp - 12V to 24V incandescent lamp.



I noticed a better response from lower voltage bulbs. Several LDR's will have good results. I have used 10k/600k and 900r/2M. both sounded good. You can adjust or even remove R20 depending on the LDR used.
I have added a switch on my Deluxe Tremolo which disconnects that R20 that's parallel to the LDR for choppier sounds available.
The effect's response is affected by the LDR,lamp,R20 and also the voltage used running the effect. Lower voltages increases the speed of the LFO so you may need to increase R24,R25 values, which sets the max speed available,
or R26,R27 which sets the overal speed. I run mine on 24V but Kaycee succesfully has his running on 12V.
It is important to keep audio wires away from the lamp to prevent LFO noise. putting the lamp too close to the LDR also adds LFO noise.

This is the video-demo of my Deluxe tremolo;

and this is a soundclip by Kaycee, who build his running on 12V;
https://soundcloud.com/retro-electro-effects/rather-trem

Turret layouts;

[Bill Mountain]

Holy hell...we are not worthy.  You're builds are always amazing.

Thanks for putting this together.

[Mark Hammer]

Based on the video, when you say "frequency modulation" in mode 2, you don't mean pitch modulation, but rather variation in the LFO modulation rate. (I can't see any schematics if there are any presently showing).  Am I correct?

[Liquitone]

Your welcome Bill and thanks! Don't make me blush, I am rubbish when it comes to engineering and math, but hopefully I make it up by imagination.

Hmm, the schematics should be there in the post Mark, atleast they are on my screen.  with 'frequency modulation' I mean modulation of the audio-frequency by the fliter-caps, not the rate of the lfo.

[Mark Hammer]

Sadly, there are many graphics which are blocked to me at work (well, blocked to us, not just me, although.... .)  I look forward to taking a peek tonight.

[Liquitone]

Are you telling me my schematic is regarded as NSFW?? how rock n' roll! 

[midwayfair]

Are you telling me my schematic is regarded as NSFW?? how rock n' roll! 

Well, your wiring is dead sexy.

[Mark Hammer]

Are you telling me my schematic is regarded as NSFW?? how rock n' roll! 

All image archive sites, including the layout gallery here, are deemed NSFW.  Although we can view Youtube and Streetview and a variety of streamed media, we are strongly discouraged from using them.  IT looked at the annual costs to our organization of the total bandwidth, and came up with a figure of roughly $176k attributable to data-intensive sites.  So we stay away from all that stuff that we CAN access unless necessary....or bored silly. 

[duck_arse]

erm, your layout diagram above seems to show Q1 in 3 different places at the same time. is Q6 really a bc109c?

[Liquitone]

I knew I must have made some silly mistake somewhere, I'll fix and update the layout. I find when I make these files I tend to overlook a lot of simple things.
Q6 should be MPSA13. I probably made that mistake cause I used a BC109C for the lamp-driver in my deluxe stereo vibe.

[duck_arse]

a bc109c turns ANYTHING into a deluxe, in my experience.

[Liquitone]

haha, yes. I chose the 109C because I had it laying around and it can handle quite a lot of current.

[kaycee]

 
That's a mammoth and cool post there LT, very generous of you. If you allow and at your discretion I could post up my drawings of the veros  for this. They are slightly different to yours, mainly in the amp section, but easily built to your specs, or maybe I'll redraw that one for it. I have separate boards for amp, lamp, power supply, switch caps and am having a play with RG's LDR conversion for the speed control as the dual 100k C taper pots are v hard to find. RG's method would allow use of a single 100k C taper pot (a dual 100k B isn't that great bunching up the fast end of the adjustment ) or any other taper single that might suit.

Not that I'm trying to discourage anyone from having a go at the point to point method, even those that appreciate how skilful your work is perhaps don't realise just how difficult it is to build that cleanly. But do bear in mind, a vero makes it a lot more accessible to builders if you don't want it out there that much....

[Liquitone]

I don't mind that at all Kaycee, I think it's great you want to share your findings, adaptions and vero layouts in this thread, so please feel free to do so.

I have tried that LDR conversion in the past and it can be very useful if you can't get the dual pot, or want to control the speed remotely or with an expression pedal.
I went for the dual rev log because I can get them quite easy, and that simplifies things a lot.

http://www.newtone-online.nl/catalog/product_info.php?cPath=27_119&products_id=1568
or;
http://www.okaphone.com/artikel.asp?id=454769
for Uni-Vibe/Wah Shell projects.
Sadly both are in Dutch with no English language option.

[midwayfair]

Liquitone, thoughts on using this bulb and running on 18v (via an LT1054)?
http://www.smallbearelec.com/servlet/Detail?no=1141

And can you explain the reasoning behind 24V regulated supply with a 12V bulb?

[kaycee]

Ok, thanks for permission. Wont be till next week as ive got a few jobs on around the house this w/end. I used the LT and regulated it down to 12v because I was using a 12 volt lamp. I was also concerned with sag. Using higher voltage will just give you more headroom and I've pushed this quite hard and it doesn't seem to clip.

[Liquitone]

I started out with the circuit running at 24V for high headroom indeed and used a 24v lamp as well, but I found using lower voltage lamps gave me better response.
When I used the 24V lamp I couldn't get the brightness vs. the light on/off response I wanted, and that caused the effect to sound very dark on some settings with the Glow knob below max. The lower voltage lamp worked much better, but I kept the 24V for the high headroom.
That 18v lamp with the effect powered with 18V might work in mode 1 (I have build a 18v version of the standard tremolo with a 15v lamp which sounded good), but it may affect the other modes. Kaycee's 12V/12V sounds just fine though.

[kaycee]

Here are the drawings for my vero version of this. The amp, LFO, charge pump and regulator, capacitor switch, and the LDR speed control are all on their own boards. Its probably not a bad idea to keep the amp and LFO boards separate and the others amalgamated as your layout/space restrictions require. I got the two main boards, power and caps board in my build, but it was a squeeze and took some planning. I haven't tried the LDR speed control, but I've used the idea before and its a simple little layout so most likely okay as is. I would recommend star grounding this.

Amp section.


Lamp/LFO


Satelite boards


Probably not for the inexperienced. You need to consider that the lamp and amp LDR are to face each other in your layout and make space for that big ol rotary. If you have a 12 volt PSU outlet you can save space running from that, or try an 18 volt supply. If you do decide to build, then do so alongside the schematic and consult LT's notes on lamps and LDR. If anyone wants the original scanned drawings drop me a PM with an email and I'll beam them over. Hope these are of some (non-commercial) use.

Heres the inside of mine for reference:

[Liquitone]

Thanks a lot for contributing kaycee! This is very useful for those who are put off by the turret build-style, which I admit has a bit of a learning curve.
I loved the recordings you made of your build, I though it sounded pretty good.

[kaycee]

Happy to give something back. There's an error on the lamp section, so I'll update that later next week and mark as updated. Power section is fine, I'll also try and confirm the LDR speed control conversion.