Quote from: J M Fahey on December 21, 2009, 05:37:17 AM
[scratching my head] 
What IS a digeri something? he he
A brief explanation, some pictures would help a lot. Same with some MP3  8|

Arrh hah! Miss Paloma forgot to tell you about that unique Aboriginal instrument,, :lmao:
http://www.youtube.com/watch?v=KBheMAfz2rc&feature=related

Trick is you have to breath in through your nose while *continuisly* blowing rasberries through a hollow log. A most basic instrument with amazing sound possibilities.
Phil.

Quote from: billyjoe24 on December 19, 2009, 12:45:39 PM
Okay. I think it's the wrong output transformer.
According to information I have from someone who has a hum free Hiwatt it's supposed to be an output transformer labelled MOT 21 GT C310.
Mine is labelled MOT 21 GT 0310 . Don't know what the difference is.
Would this cause these problems I've mentioned?
The Power transformer labels match.
Any ideas?

NO!!  that's about as reliviant as the lunar cycle :duh

*Heater Ground reference First*,,, Until that is known I doubt anyone can help.
JMF has explained all that part already?

Then establish all Com points are in fact at zero,,
Then check diodes are all ok then check All PSU Electros.
(one might have gone open causing excessive hum)
Phil.

Quote from: kvandekrol on December 18, 2009, 04:24:27 PM

Quote from: phatt on December 18, 2009, 09:49:29 AM
BTW,50 pot looks like it will work better,, less boost but more refined tone.

One more request... If you saved a copy of the test file you used to generate the simulation for the 50k pot, is there any way you could run it again using the 250k (which is what I have now) so I can see the difference on the graph?

Thank you so much for your help so far.

No worries,  The graph shows response of both 50k and 250k pot.

Note the use of 50k pot maintains an overall bigger output even with mid boost fully off.
That will make a sonic difference in the way you might percieve the outcome.
So my guess,,,The Elite circuit with 50k will always seem louder, more in your face.

(Note; take my earlier comment of 50kpot as a mistake)
Now that I've had more time to absorb it all the 250k pot (at full off) brings it down closer
to a *flat response*, to me that at least makes it possible to do a comparison with a normal strat.
Your ears will have to make a judgement on which is better.

If you want to go nuts with the circuit then C3, R6 and C13 are the ones to mess with.
Try C3= 15nF,, R6= 2k7,, C13= 2nF.
This will lower the boost point thus allowing more useful (audible) frequencies between 1kHz
and 4kHz to get through. There is only about 14 Db of boost at 3kHz but see that the rest of the bandwidth comes up also ,, hum Head scratch.

So in effect there is only 4 Db of difference. IMHO not worth all the fuss.
Again only you will know what works best.
Remember there is very little benifit of boosting frequencies above 10kHz if anything you want to suppress them.

Between 6kHz and 10kHz will add some sibiliance to the upper harmonics but past 10kHz is just not audible through a normal guitar speaker, if it is audible you likely have a horrible amp speaker setup.
Note the vertical red line at 10kHz, so blot out anything above that line.

I've added the Mod curves after playing around with C3 and the other values to give you some idea of what will happen.
Have fun with it all, Phil.

Actually there is a bias voltage on the "mini mixer", so just run off that bias point.

Don't worry about 9 or 10 volts as a lot of these opamps run anywhere from 6 to 30 volts. 9 volts is a little low actually and you tend to waste a lot of battery life because some opamps suffer when the 9v batt runs down to below 6 volts.

From memory a TL062 is a good one as it still works at 4volts, or there abouts, not as high speced as others but still a very usefull chip for low voltage battery situations.

The best bet with these circuits is to run 2 x 9volt batts in series giving 18 volts and you will probably tripple battry life.
Just remember to use 25volt rated electro caps and you will be fine, 16volt caps will likely explode or leak if run at higher that rated voltages.
Rule of thumb for caps is allow a 25% margin of safety and they will last a long time.
So if you have a 9volt battery and your caps are 10 volts then you have no margin for error and the caps will certainly fail sooner or later.
Phil.

Quote from: kvandekrol on December 17, 2009, 05:57:27 PM
I was also against active circuitry until I played this guitar! It may not work as well with all amps, but with mine on the right settings I can play clean with the guitar's volume on 6, have a very sweet overdrive on 8 and a heavy overdrive on 10. I'm not too picky about having vintage or classic tone so it's perfect for me.


So, short of buying an Elite preamp from eBay for the buffer, my other option is to install some Lace or Noiseless pickups and remove the dummy coil... but then, low-noise or noiseless pickups have a much higher impedance (usually 10-12k), so it probably wouldn't be much different than using a dummy coil...

I am coming to realize how ridiculous this all must sound! but I am fascinated by the sound of an Elite, and am very interested in reverse-engineering exactly where the tone comes from, so I really do appreciate all the help.

If I had money to bet, then the *Elite* pups.
With or without Dummy load they are likely to be potted rail pups, overwound.
They are certainly very different that any other Fender pup.


You have the dummy coil and the circuit schematic why not just build the extra circuitry and run the dummy load like Elite?
Then you can make your own judgement.
No matter which way you wire it all,, the dummy is to up the winding which will fatten it up.

My old one time Elite owner mate just told me that the advertizing blab was to make it Fat like a humbucker,, which will subdue the hum somewhat by design. So Hum may not have been the reason for the dummy.

BTW,50 pot looks like it will work better,, less boost but more refined tone.
Phil.

Hi madapj,
              The Hum maybe due to not having the *Circuit Common Grounded to the Case*?   I can't seem to see that in all those pictures.

Nice neat work by the way :tu:
Phil.

Hello pyromaniac,
Just look for something that *isolates* ie Hi Z buffer.

They should look something like this below.
Drawn off the top of my head , so I may have missed something but enough eyes on here to correct it or refine it for you.
I assume you know how to develop a *bias supply*? If not I'll draw it when I have time.

Don't worry about the language,, you are doing just fine.

Have fun, Phil.

Quote from: kvandekrol on December 16, 2009, 06:11:19 PM
Also, I should mention that my guitar is a Powerhouse Strat, which is essentially a MIM Clapton. It uses the exact same preamp board except that its output has been reduced to 12dB like the Elite. (I couldn't find any schematics specific to the Powerhouse which is why I referenced the Clapton.)

It has American Standard pickups in it rather than Clapton's Lace Sensors. It also has the hum-canceling dummy coil just like the Elite, except it's wired in parallel right after the pickup selector rather than having a separate wire coming out of the preamp board like the Elite (thus no need for a buffer stage to drive it)

Hello again kvandekrol,
Found the time so have a look.
Response curves using *Your EC circuit* except I've simmed it with a 50k pot instead of the
250k pot.
First thing I noticed is that it's got heaps of cut/boost BUT way to high in the bandwidth to
be of any real use.  I would hardly consider this as a *Midboost* circuit,,Treble boost more
like it.

The 10Db of boost is only happening at 10kHZ which is at the very outside edge of what your guitar can possibly produce so any real mid boost your ears hear is only a couple
of Db at 3/ 4kHz. Heck even an hobby nob like me could do a better mid boost circuit.

As you may have noticed I don't get excited about active circuitry in guitars as a well
designed Amp can do a far better job of mid boost and they don't chew batteries  8|
but I'd guess from reading your post you really want to fiddle with this so having spent an
afternoon simulating this the best suggestion is Fiddle with the value of *C3 .0068uF* which is 6n8 or 6,800pF.

Try 10/ 15nF ,, even 18nF,, past that you may as well forget it. (but try more if you wish).
15n will make the boost more active from just under 1kHz which is still very high for my idea
of midrange but you will definitly notice a difference.

Just a note in case you have trouble with freq.
Midrange for guitar signals is 300/400 Hz. 700Hz is upper mid, past 1kHz you are in the treble range.

Be very aware that you can never get the *natural sound of the pups* with a circuit such as this because the treble boost (sorry mid) is created in Q1 and the mid pot just cuts or boosts this basic tone shape. It actually boosts all frequencies but just more emphisis on the high. (There is no *Flat point* where the frequency is left untouched by the active circuit. it's always on and altering the tone shape.)

Oh yes from my understanding the MIM deal was cheap pups (ie, Ceramic magnet blocks Under steel billets, Not real alnico billets)
Nothing wrong with that as some Ceramics can sound very good,,,you just have to be carefull not to wind to many turns as the ceramic will then get harsh.

Hope it helps you out a bit.  Phil.

Hi kvanderkrol,
              Ouch yes a tricky one to sort.
My guess, though they look similar they are very different.
Short answer is change the 250k pot back to 50k pot and it will be less boost,,,
As to how much?  Well you would just have to try it.

I don't believe that the *Dummy load* is just for noise cancelling, I think it was there for loading? Not sure?

The pup's are also very different as the *Elite* uses the tried and tested old pup design.

The Elite also has a very unique pup selector, being 3 push buttons instead of the 5 way.
If I remember correctly All 3 pups can be engaged at one time, any combination with Elite.

After a brief look at the two schematics there are at least 6 or more different values that would impart a different outcome to the tonal effect. C1, C2, C5, R4, R5, R13.
Edit (numbers from the clapton circuit)

IMHO far to much muckin about for very little benifit.
I have a friend that owned an Elite and the only great benifit was the onboard volume worked like a built in OD stomp box. kinda handy but yep an absolute pain when the battery went dead.
I agree with JMF comments, without a passive bypass mode it's un-nerving when the battery is low and you have to break into a big leed part.

Bare in mind that with these PCB's once you start unsoldering and resoldering the tracks can delaminate and you can end up with a dud pcb.
Just thought I'd mention it as some people forget that a lot of these old pcb's would be darn near impossible to replace now.
Phil.

oop! almost forgot,, For an indepth read go here,
http://www.ssguitar.com/index.php?topic=707.0
I have not read it all but these chaps know more about it than me so you will likely learn more :tu:
Phil.

Hello Josh,
              I''ll Explain this the old simple way,,it's easier to get your head around.
When it all boils down there are really only *2 types* of speakers they being
*High Complience and Low Complience*.(HC/LC)

If the cone has a rubber surround and the voice coil moves in and out a long way with ease then you have HC Speakers. HiFi Woffers, douf douf bass drivers/add some of the surround sound gear to that list.

HC are designed to *Comply* with a specific enclosure box. They don't produce the energy very well without the box. (they can actually destroy themselves if driven hard with no box).
Generally HC are used for Bass drivers in *PreRecorded Music Reproduction*


Music Instrument and Live PA work is mainly covered by LC speakers.
These have no real need to *Comply* with an exact box enclosure (though it can help)
as they have very *Short travel* Voice coils (VC).
Some LC driver cones are so stiff they hardly move even with a big signal.
Looking at the cone edge you will see a rippled edge (often called the spider)
to allow for some cone movement.

So Just like cars.
There are many cars but some have a different purpose.
ie, You would not use an F1 racing car in a mud rally whould you?

All that said there are some (usually older type) car speakers that used LC speakers often for door mounting and like and on the rare occasion you maybe lucky an find a pair that can work well in a small open back box but still it's probably easier to just purchase a real guitar speaker and be done with it.
Have fun Phil.

Hi Hasss,
Q1/ "Any proposals on a good tone stack?"

I believe I've given you one already.
PhAbbtone built *AS Shown* will be better than most circuits found on the net.

Any Hi Z tone stack between the Ruby and LM3886 with no Extra active commponents will likely not be rewarding. There is every possability that the results will be dismal. Signal will pass through but the output will be quite low and tone controls will not work effectively.
I can't promise great tone if you try to short cut my circuit.


Q2/  "Because i don't know much about tone stacks i would like to ask something.  Why your tone stack is passive when there is a op amp? Sorry for the stupid question."

The only dumb question is the one not asked.

Yes it is somewhat confusing, My circuit is a *passive tone control circuit* and is also a *Passive input* device. ie, no *Active preamp* in front as is the normal case.

The word *passive* here is being used here to decribe 2 different situations.
Re the baxendall, they work in a diffent manner,, some folks like them but for me they don't work as I would like.
If my memory serves me correctly my reading remembers that *James* was a passive tone circuit and *Baxendall* was a James circuit used in a feedback loop and does actually have some gain.
(The word Baxendall has stuck and is used to decribe both.)

Just google some of these trems and I'm sure you will get some indepth pages of interest to read up on to better understand these things.

My PhAbbtone circuit is Odd/ different simply because it has no active front end like most amp circuits use.

So having built all the common tone stacks, Valve powered and SS powered.
I've come to understand that the active front end is not really needed with modern hi gain magnetic pups used in modern guitars. Most player use floor pedals or processors anyway so it will make little difference.
It will struggle with an acoustic *Peizo Pup* with No Onboard preamp when used alone but as most Acoustics today impliment onboard preamps then again it's unlikely to be a problem.

As you wish to use the Ruby in front then none of this will ever be a problem.
Phil.

Welcome Pyromaniac,
                             That circuit is for pedal mixing, No good for passive joining of 2 guitars.  You need two hi Z isolating buffers for the job your asking.

The 4x 10k pots will serverly limit the usefulness unless both guitars have active pu's OR both guitars go through pedals that are always ON or have the last pedal in the chain with a dedicated *Buffered* bypass.

I did know of a simple circuit but for the life of me can't remeber where. I'll head scratch ,,see if I can track it down.

Some advice,
If you where mixing two acoustic players into one input the concept has merit but if one player has lots of pedals and the other player has none then you really need to use 2 Amps.
Phil.

Hi hasss, 
         Just thought I better comment as there are some traps here I think.
Running a passive tone circuit *Straight into a chip PowerAmp* maybe a big let down.

I'm not familiar with the chip mentioned but most of those poweramp chips have a rather lowish input Z (input impedence) and as such are not capable of working well with any of the Tree type Hi Z passive tone circuits, including HiWatt.

My guess, The PhAbbtone circuit will be a waste of knobs, it will still pass a signal but the loss will likely be massive.

As the PhAbbtone is my own design/ concept I hope you can appreciate/ understand that if you change it to much I can't promise a good result. 8|

There is a lot of voltage loss (signal strength) in All these passive tone systems but nearly ALL the Valve circuits have very high impedence (including the power amp stage) so the loss is not as noteable when used in Valve circuits.

SS amps often use an *Active tone setup* which has no loss and can be used in low Z circuits but as is often noted some of the *Valve magic* is due to the Hi Z tone circuity used in the amps of old days.
Hope I did not dampen your obvious desire to DIY.
Have fun, Phil.

Opp's forgot to say.  I'm assuming your Acoustic guitar has a built in preamp?
If NOT?   Then you need a different setup.
Phil.