My effort at tone controls.
Ok "Zappacat and sergscar" have asked for this one so here it is;
The "Tonemender circuit" has been mentioned more than once on these pages and although it works it could be quite easily improved. No disrespect to ROG but I get the impression not much effort goes into "Refining" there ideas. Nearly all these old styled passive tone circuits are quite prone to picking up noise but if you know your way around it they can be greatly improved. At the very least this will give DIYer's some other options to choose from that
I think most will find superior.
HiWatt tone does not get much mention (probably because it looks a little tricky) even though it was the best of all the famous tone stacks. In fairness it's no better than the classic Fender in regard to the Amount of bass and treble but the midrange cut leaves fender types for dead.
I doubt many will read all this but I have built a lot of these old circuits both Valve and SState so I'm fairly confident in stating how well they actually DO or Do Not perform.
If you are just hell bent on replicating a specific tone circuit then It should become obvious that you can use most of the old tone stacks in place of mine if you so wish.
For those that wish to replicate the EXact HiWatt circuit be aware that the bass pot was a *TRUE LOG* 500k unit and you may have trouble sourcing those nowadays. What is often sold today has a psudo log curve and will be very disappointing in use.
I've tweaked the components for what I think is the best mid freq Q point and max cut, it's around 400hZ.
Play around with the values if you so wish but what you gain at some place you may loose out elsewhere. Like all the other tree type tone circuits the controls are very much interactive. There is No Gain/Boost with passive tone stacks so the game plan is all about making the biggest difference between frequencies. A deep notch cut is what you want as shallow scoops tend to sound unconvincing or bland.
Side note;
My Alesis Micro EQ cannot deliver the 30/35Db difference at 400hZ when compared to the passive HiWatt even though the Alesis is an Active parametric device,,, and yes I A/B tested this many times.
This schematic is version 2, which is better than the original circuit that I've already posted on this board. I've built 8 of these units for mostly working musicians and over time it became apparent that the noise/hiss
was an issue with some Hi gain Amps. This is all good because it forces me to work harder and find better ways to implement the circuit.
Very low noise opamps might help in extreme situations, I've used both TL072 and LM883 and you can hardly pick the difference by ear.
Be aware that altering or deleting R5(10k) will just increase the noise in quite a dramatic fashion but not the gain.
I discovered from some in-depth reading that this is how to do it and keeps the noise down. The 10k/10k voltage divider network (R5 and R6) seems to deliver the best results. Some here may have even better ideas so feel free to comment.
Also make VR4 100k lin or log if you need more power to drive your amp but don't go mad here as the noise will climb fast. The intention here was to just use this to balance the bypassed sound level and is not intended as a high gain section,, there are plenty of those around so use them for gain.
A good understanding of wiring up high impedance circuits helps as well. For those that may not fully understand,, Everything above R1 R2 R3 R4 in the tone stack is going to be prone to picking up unwanted crap,,
so just use metal film R's for the whole circuit and be done with it.
What! No active input? :duh
One of the not so obvious subtleties of famous valve driven tone stages was the simple fact that the output of the tone stage had a natural roll off in the high freq response.
With an active opamp buffer stage front-end this may not happen so by using the tone passively you are likely getting closer to the original Valve Tone effect. The passive tone stack input imp is plenty high enough for the magnetic PU's used in electric guitars.
Feel free to use a buffer in front but don't expect it to be vastly
improved.
When players first hear this box there is often a comment about the presence/brightness,, so again attaining more hi freq will likely render it more SState sounding which is the very thing your probably trying to avoid. so your call.
And for those that think it can't work passively you need to go way way back as this was how it was done in some early equipment.
How to use;
The treble dominates the tone in old standard fenders and I wanted to avoid that as much as I could. So if you want the treble to sparkle with this one,, just turn down the mid as it is now the dominant control.
I've deliberately tilted the output slightly to the treble freq but without loosing to much bass.
If you want more bass make R1 smaller, try 56k. Lower values will likely upset the mid cut ability.
Now I've bored you long enough so here's The schematic and some pictures that might give you some ideas of how to build it. I use the old printer selector boxes, you can pick them up for next to nothing as they are of no use anymore.
I do this cause someone may as well benifit from all my frustrations of trying to get a decent sound.
After 20 plus years of fiddlin with circuits,,, on rare occasions you have a win and I think this is one time I did pull something off that actually worked.
Have fun with it, Phil.
*Edit* Just a note, Scroll down for the up to date SCHEMATIC. Cheers, Phil.
Hi Phil,
Thanks a lot for your post !
I'll squeeze my brains (with the help of the "Eagle" PCB software...) to create a PCB layout and proceed building the circuit.
I don't know if I can find the "printer selector boxes" here but, if not, I'm pretty sure some alternatives may arise.
Keep you posted abt outcomes !
B'rgrds,
Sergio
Hi sergscar,
Here's a pic of how I do it,,, might help?
I use eagle but I do the boards by hand as most of my stuff is simple and for one off's it's not worth all the bother.
I just use a fine tip oil pen and etch the thing, Eagle just helps to keep all my centre pops exact. I print out a mirror on paper tape it to a blank,, lightly C pop all holes,,,then just join the dots,, etcxh and drill.
Of course you would not do it like this if you went into mass production. :loco
Note: This is the earlier version so it's not exactly the same.
Cheers Phil
Hi Phil,
Big help, of course !
I already had "throwed" all the components inside "Eagle", but some doubts always arise, and the picture clarified most of them.
I've installed Eagle a few days ago, just for doing the "Passive tone circuit" and takes some time to learn the "how to" (in particular, I'm feeling some difficulties for finding the right components in the libraries). Maybe there are easier softwares out there.
Just one more question: COM1, COM2 and COM3 are the Ground connectors for "IN", "LED/-Vcc" and "OUT", respectively ?
Thks again !
Quote from: sergscar on May 27, 2009, 09:31:08 AM
Hi Phil,
Big help, of course !
I already had "throwed" all the components inside "Eagle", but some doubts always arise, and the picture clarified most of them.
I've installed Eagle a few days ago, just for doing the "Passive tone circuit" and takes some time to learn the "how to" (in particular, I'm feeling some difficulties for finding the right components in the libraries). Maybe there are easier softwares out there.
Just one more question: COM1, COM2 and COM3 are the Ground connectors for "IN", "LED/-Vcc" and "OUT", respectively ?
Thks again !
I've been doing the same thing. What did you end up using for the variable resistors/POTS in the Eagle component library? Also, are you sticking to a particular size/brand when it comes to capacitors and resistors? I wish I knew more about this stuff but I'm taking a stab at it anyway. Anxious to hear what Phil has to say about the above question of yours. I found this link http://www.sparkfun.com/commerce/tutorial_info.php?tutorials_id=110 (http://www.sparkfun.com/commerce/tutorial_info.php?tutorials_id=110) when learning about Eagle. It may not apply to this project but it's interesting and informative. I'm making an LM3886 right now just to get used to the Eagle component.library editor.
Hi Zappacat,
As I told before, i'm also in the 'learning phase', and I'm very impressed, since I discovered that many shcematics you find in the net can be reproduced by this mean.
You can search the components within the libraries by clicking the "add" button in the left tools' panel, since this will show you search box (down-left).
I quote, here below, the ones I used:
POT: TRIM_US-CIP20C-6MM .
Resistors: R-US_0204/2V (you can change the 2V for something higher...)
Capacitors: CPOL-US085CS-1AR should be ok... (those have polarity)
IC: TL072D (you will have to add it in 2 parts in the schematic, since the pins are splitted in 2)
Power supply: +18V
Jacks: DCJ0202
Led: LED
Diode: 1N4004 (you can change the value...)
Capacitors (wout polarity): CYYC7B5
I guess that's it...
Maybe the components I used are not the right ones, but I guess they accomplish with my needs of designing the board.
Concerning the "tutorial", I do suggest you to download this file:
ftp://ftp.cadsoft.de/eagle/userfiles/doc/veic_pcb_layout_tutorial_010709.doc (http://ftp://ftp.cadsoft.de/eagle/userfiles/doc/veic_pcb_layout_tutorial_010709.doc)
In my opinion, this is the best tutorial you will find outthere.
Hope the above of help
regards,
Sergio
I'm missing the power input stage, the input and output jacks and I need to change the symbols for some of the polarized capacitors. I'm not sure where the ground symbols are in Eagle. Also, are there input/output jacks in Eagle? What heading are they under? Where are the batteries?
I guess I screwed up on the TL072D. I found something with similar name(TL072P) and appearance and just dragged it onto the circuit. Please tell me what other errors you see.
Thanks!
Here's what I've got done in Eagle so far:
***Linked content removed due to malware***
Have you downloaded the GM libraries for Eagle? It is set-up almost perfect for most of the stuff we do here. I'll see if I can find a link.
here ya go. Click on the link and follow the destructions.
http://gaussmarkov.net/wordpress/tools/software/eagle-cad/ (ftp://http://gaussmarkov.net/wordpress/tools/software/eagle-cad/)
First my sincere apoligies as I fluffed the schmo,, opps.
No pain as it works both ways which is why I probably gooffed it up cause I've built it both ways and my ears can't tell the diff. A sim reveals very little difference also.
Just the same I should have been more careful. :trouble (the bats for me.)
Obviously a little trouble with Eagle.
So here goes;
1/
Pots are *piher PC16S* these are very close to the 16mm pot I use.
2/
Com1,2,3 are just *wire pads* renamed you just have to give them different names.
3/
If you want to change a component just click the little *spanner* and select *package*
this brings up the part list again.
4/
I struggeld with opamp packages so I just used the *dil* and select dil8 for my needs it's fine as you know the pinouts.
Zappacat note that VR2 and VR3 have the wiper not connected, you need to fix that.
As I don't mount the sockets on the board there is no need for them which is probably good cause I've never found a part that comes close to standard 6.5 either.
I have found those onboard mounted sockets can be a pain and are often the thing that breaks down first.
so standard chassis mount and hand wire up for me.
Again sorry for stuffup, I guess my only excuse is it a hobby and I'm not making money from it. thanks Phil. Here is a couple of shoots of my file.
Quote from: iTzALLgoOD on May 28, 2009, 09:33:18 AM
Have you downloaded the GM libraries for Eagle? It is set-up almost perfect for most of the stuff we do here. I'll see if I can find a link.
here ya go. Click on the link and follow the destructions.
http://gaussmarkov.net/wordpress/tools/software/eagle-cad/ (ftp://http://gaussmarkov.net/wordpress/tools/software/eagle-cad/)
Thanks I'll look into that myself but not until these chaps have sorted their issues.
I hate updating programs in the middle of using them as something always goes fut and you end up in a nightmare not being able to find /access a file.
Cheers Phil.
Now, I've made it to this point. Please critique this Eagle schematic. I know I've got some things to clear up. Specifically the implementation of :
IC: TL072D, capacitor polarity, battery source?
I can't find an exact match for 1N4001 or TL072 in the Eagle libraries that I have. Any suggestions?
Any feedback greatly appreciated.
***Linked content removed due to malware***
Hi, by the time being, detected some items to adjust:
- Polarity of TL072 is inverted, therefore, you'll have to change the connections accgly
- Polarity of Battery, Led and 1N4001 are inverted
Also, pls note Phil marked some changes on C3 position (check his previous post), and yours is still unchanged
I will try to follow his new schema, and post the result later
Poor Phil, he will have to be patient with both of us... 0:)
I thought you chaps where going to breadboard it all first?
But hey if you want to just dive in I'll help as best I can,
Phil.
Just adding Something to help you understand why this works so well.
Here is a snapshot of shootout between the *Tonemender and the PhAbbTone*.
Tonemender is average, at around 13dB cut in the mid.
The PhAbbTone big mid notch is clearly evident and my 30dB cut claim is really quite conservitive.
That deep mid notch does amazing things when used in front of even the most basic tube screamer OD pedal.
BTW all those frequency altering switches and add-ons only really shift the mid point up or down a bit and in reality are not much use (IMO)
I have built The famous Dumble tone stack and it's another one that shifts the mid around but nowhere near as powerfull as the HiWatt setup.
Cheers, Phil.
Quote from: phatt on June 08, 2009, 10:12:16 AM
Just adding Something to help you understand why this works so well.
Here is a snapshot of shootout between the *Tonemender and the PhAbbTone*.
Tonemender is average, at around 13dB cut in the mid.
The PhAbbTone big mid notch is clearly evident and my 30dB cut claim is really quite conservitive.
That deep mid notch does amazing things when used in front of even the most basic tube screamer OD pedal.
BTW all those frequency altering switches and add-ons only really shift the mid point up or down a bit and in reality are not much use (IMO)
I have built The famous Dumble tone stack and it's another one that shifts the mid around but nowhere near as powerfull as the HiWatt setup.
Cheers, Phil.
How did you plot that graphic out like that? Is it some form of oscilloscope? Do you hook up your guitar -> tonestack -> input on your scope or computer and strum the guitar? You have me perplexed!
Hi Zappacat,
No I can't afford all that kind of $teck test gear$. :(
This is the cheats way,, It's called *Computer Aided Simulation*.
I use Circuitmaker, the student version (Free up to 50 components)
Like all modelling don't rely on it as perfect but It gives one the ability to grasp what kind of Tone response you are likely to get from a schematic you wish to use,,, makes short work of stomp box circuits.
Say you're breadboarding a circuit and your not sure where your loosing the bass?
well Sims can help ,, Draw up the schematic on screen then just click on different parts of the circuit and it gives you the AC plot *at every point* in the circuit.
Quite frankly it's put me light years ahead and I highly recommend it,,,
Even if your understanding of electronics is limited (which of course includes Me)
it won't take you long to catch onto how it works, and how to use it.
If you are good at software/computers and you know how to find the signal path through a circuit,,
then you qualify.
Test whatever you want,, even if it's way wrong,,,heck you can't blow anything up with sims! There will be some setup paremeters that need to be tweaked to get the AC Analiysis happening.
Being able to *SEE* just how much the tone shape is altered and Which part is actually doing the distorting as it passes through each component opened up a whole new world,, hence my grasp of how amps work (TONE) is vastly different than the early days of just thowing money away on every new gizmo.
Cheers, Phil.
Hi Phatt, thanks, I´ll give it a try.
So far I´ve been using the "old method", you know, with soldering irons that burn you deep if you grab them the wrong way, components that burn, smoke, crack, etc.
I think it will be a way of saving some $$$ and also uttering wild expeletives such as: "!@#º$%&/()=?¿\|" >:( :( ::) :-[ :-\ :duh :trouble :grr .
Bye.
J M Fahey
Quote from: J M Fahey on June 10, 2009, 11:28:09 AM
Hi Phatt, thanks, I´ll give it a try.
So far I´ve been using the "old method", you know, with soldering irons that burn you deep if you grab them the wrong way, components that burn, smoke, crack, etc.
I think it will be a way of saving some $$$ and also uttering wild expeletives such as: "!@#º$%&/()=?¿\|" >:( :( ::) :-[ :-\ :duh :trouble :grr .
Bye.
J M Fahey
Oh Yes all of that is what I wanted to avoid,, so I'm in love.<3)
From reading some of your posts I doubt you will trouble finding your way around.
I used the word *cheat* because I do realise that to do this in the good old days required a lot of maths and geometry skill.
So I feel somewhat privelidged to be able to press a button and Bingo, have it all done in the blink of an eye.
You can't help but respect those folks who burnt out pincils and brains to plot a curve.
The thing that really struck me about plotting amplifiers in general was the very different way SS and Valves work. SS is kinda a dead flat response whereas tubes are very specific in there response curves.
Though you can make tube gear HiFi flat but they don't sound good then.
In the end I had one of those enlightening moments and kinda realised that the whole game is about the tone curves ,, one response running into another,, to my limited mind this makes sense and from that any guitar player like *ME* can at least start to grasp the idea of tonal manipulation. The marshall simulation trick found on JTM 30/60 Marshall Amps is a classic example of how to go about reproducing specific tones.
From what I've read Teck21 use similar circuit tricks to capture the tonal signiture of certain amps.
Have fun,, Phil.
Phil,
I was wondering if you've ever messed with any of the 18watt related stuff? I just got the parts for most of my 18watt build which consists of an old Hammond AO-43 amplifier chassis with components and a universal 18watt turret board. My goal is to build an 18 watt variant of the 1974X but I'd like to use your tone stack in lieu of the standard 18 watt TMB tone stack found on most 18watt schematics. Have you ever integrated one of your passive tone circuits into a classic tube amp? My ultimate goal would be a 1974X tremolo with VVR and your tone stack. Is this a realistic goal to pursue or am I missing some problematic issue here when it comes to combining those elements together in the same amp?
Thanks in advance!
Oh dear,, the tube amp Bug has bitten you ay?,,, have fun.
1st answer;
YES,, absolutly any of those tree type tone stacks can be used in just about any tube amp.
I have no doubt that HiWatt will give a bigger mid cut than the others.
with the mid *full off* there might be a smidge less gain in the amp.
I opted to chuck tone stacks in tube amps because they just waste triode voltage gain,,, that's why I built the PhAbb Tone box, it just simplifiys a whole lot of hassels. ie, I can use any amp and get the same tonal signiture happening,,,, whereas if you wack a tone stack in a tube amp you can only get that tone with That particular Amp.
I only have 4 Valves in my rig,, it's very much like a Fender Pro Junior.
Volume and tone cut knobs only.
ALL the rest is done via SSate gear.
http://www.ssguitar.com/index.php?topic=1064.msg6521#msg6521 (http://www.ssguitar.com/index.php?topic=1064.msg6521#msg6521)
Read 4th post on this page for a more complete coverage of how my ReAmp System works.
The VVR thing works but I've found this to be more rewarding as you can do some Very slick post power amp tweaks.
Any tone within reason I spose,, at any SPL I wish to dial in.
Cheers,, Phil.
Ei, i want to save some money, can i use 500k pots instead of 250k pots in your design?
Thanks!
Hi Tom, Only the Bass control can make use of 500k :'(
And even that comes with a BUT,,,,, and it's a big one.
The 500k **LOG** pot you can buy off the shelf at electronics warehouse stores is likely to be the modern ***Fake Log*** pot And these will be very disappointing in use as all the bass is between 1 and 3 and nothing will happen after that.
On the other hand if you *Do* happen to have some genuine log taper pots (i.e. 10% of total resistance @ 50% rotation) then yes use them.
***Remember the Mid and Treble are Linear,,, only the bass is Log***
You can use 250k for both Treb and Mid and even 100k Log for bass.
It just changes the interaction between controls. I wanted the mid to have more control than the treble otherwise you end up back at good old fender where the treble overides everything. :grr
Truth is 500k won't do much for guitar as the larger value only boosts freq below 100 Hz and as the lowest freq on guitar is about 80Hz you won't even notice it.
Bass Amp tone stack with big Amp driving a couple of bins,, then it will then be heard.
If you are breadboarding it all then heck try anything out and see how it sounds before you build.
Have fun,,Phil.