phatt's Schemo Collection

[phatt]

Hi Dogbox,
               Arrh obviously you're an aussie? :tu:
Yes the big pineapple is down the road from me.
Sadly the tourist trade has suffered in recent years and it's now all sold an no longer running as a resort.

Re the the tone box;
In a word no on both counts.

These Valve type tone controls are *High impedence* circuits which suck the life out of any voltage gain and with no Active component to recoup the loss,, it's a dead end street.

A 1 Volt signal in can be reduced to about 300 mV,, that's on a good day.
The loss can be worse if it's not looking into a very high impedence.
You can lose heaps of Bass this way and you end up with tone controls that only sorta kinda work.

My tone box was designed with the idea of just delivering Real tone control that is lacking in a lot of Amps. (yes even some Valve ones)

Re running the PhAbbTone direct into LM3886;

Having just returned from the shed after testing the PhAbbTone circuit straight into my little LM3886 sub woofer,,, You will likely need another stage.

Check my preamp circuit for LM3886 I brewed,, you will likely have to turn down the gain if you desire super clean or just add a trim pot for gain adjustment.
(look at how the volume/gain/trim pot is used on the PhAbb circuit for ideas)


Re Your idea of Clean;

Be very aware that everyones idea of clean can be quite different.
Some folks would be quite supprised to learn that Hank Marvin's Sound had some distortion happening to the signal,, even though you might consider that sound pure clean tone,, It's Not.

Some rattlin adds a certain about of body/depth to the sonic signature which is why a lot of early SS Guitar amp where a flop because they just refused to breakup at all.
Ultra HiFi Clean can be very unimpressive and boring to play.
That said I'm sure some like it.

Anyway keep reading and suck up as much as you can.
A bread board and some components will soon get you in some understanding of how it all comes together.
Have fun,, Phil.

[dogbox]

Thanks for that Phil. Yep another Queenslander, living at Beenleigh for many years I actually grew up in the 70's at Tewantin, and in those days Nambour was considered the big smoke-it used to be the capital of the Maroochydore shire council at one stage!!! Times have changed huh? A number of years ago they moved the hiway didn,t they?. In some ways that could be seen as a good thing-from what I have seen of the rest of the Sunshine Coast has gone mad-they are loving it to death...

OK then, a double-"no" to my questions - I'm thinking the Phabtone may be better suited going into my Epiphone valve Junior which has one volume pot? Not a bad little amp but definitely could benefit from some tone controls PRE the input jack as its a bit of a one-trick pony?  It does sound great with pedals though.

Will try and track down your preamp schemo-haven't found that one yet. Yeah I definitely have got the breadboarding bug and slowly building up a part stash, only working on 9v stuff so far - Ruby amp, tillman jfet preamp, fetzer valve etc etc soldered a couple of jaycar and effects pedal kits - love this stuff.

Will be getting around to doing a LM3886 kit from chipamp.com in the future-have it here, just afraid of getting zapped if/when I start playing around with mains voltages. Will probably annoy the heck out of everyone when I get started on that project

Plenty of reading to be done first though - this forum is a great resource.

cheers Mate

[phatt]

Hi Dogbox,
              Preamp for LM3886 is here;
http://www.ssguitar.com/index.php?topic=1672.0
Halfway down page.

Have a look at the gut shoots on my last posting on there, might give you some ideas of how you might build it all.
The hand drawn pcb preamp board should be rather obvious and although the main board looks complex it's only the centre bit that is used. All the rest is disconnected or removed as that is the sub circuitry and remote sense stuff.

Oh you poor man if you have to endure *Beenleigh* as it's just an extention of brisbane now.

I moved from Brisbane to get away from the stupidity of the big city it has become.
My Uncle ran a pineapple plantation (years back) at Woombye (Near the big pineapple picture shown) so I knew this area well from my youth.

Now I live here, an I love the country town feel.
Phil

[dogbox]

Hey Phatt,
That looks great. I take it that IC is an opamp? If so, which do you recomend? I have a bunch LM741's would that work??
Yes true Beenleigh is getting that way too, we were part of Albert Shire (gold coast) then swapped to the Logan Shire after the last election - so you could say we went from Gold Coast North to Woodridge South in one foul swoop

Breadboarding this pre looks like a good project for the weekend-after a trip up to Jaycar on saturday morning.
cheers for that..

[phatt]

Hi mate,
Yes you can use the uA741 or similar,, just remember the pinout is different.
Ask Jaycar for a couple of LM833 dual opamps,, these are technically far better than 741 but really it won't matter much while you are breadboarding stuff.

You may find the 741 (being a single unit) are easier to work with while breadboarding.
You can setup a split power supply just with 2 x 9V batteries in series.
The mid point between them becoming the *Common or Ground* refference.

Use LM833 or TL072 when you build the PCB though.
Phil.