Hi folks,,
Been a while,, but I finally found a home for my LM3886 subwoofer circuit.

I Shoehorned it into an old UPS case. The case (like the subwoofer) was junked in a pile of unwanted electronic equipment heading for the dump.
Oh how I love junk.

Refined the one knob tone circuit only slightly.
So front panel is: Tone, Gain trim, Volume.
Only issue really was an Earth loop which kept eluding me for a day or two  :grr
but finally found the offending connection and now it's dead quite,
even when cranked.
The preamp has too much gain but I love what it does to the LM3886.
Through a 15 inch speaker it's a huge old 60's rock tone and it's loud.

An almost woody sound with the onboard controls but just adding the PhabbTone preamp in front delivers the more modern rock tones.

A whole Amp circuit in box for under $20.  I'm happy 0:)
Phil.

The Reverb bit is likely a bad RCA type lead (i.e. broken wire inside lead)
Replace leads,, or the tank maight have an internal broken wire.

Side note;
A lot of reverb circuits are designed with this major,, major flaw:
""if the pickup side goes open circuit (not uncommon with cheap RACA leads)
the amp either squeals like mad or hums like crazy.""

The next part:
You have likely stuffed something while tryiny to fix reverb.
Sorry somene who owns,, or has worked on one may be of more help with that part.
Phil.

Hi skynyrd,
What happened to *super bassy and compressed* you mentioned?

Did that get sorted?
Phil.

Hi Warlock,
               Don't know the Amp but from your comment the Volume pot might have gone open circuit.
If the ground leg on the Volume pot breaks then that will be the result.

While running an audio signal Gentle pressure around that commponent on the circuit board may lead you to the offending issue. It may only be a cracked solder joint on the board but if the pot has *internal damage* then replacement is the best option.
Pots are touchy little things and are a moving part.
Hope you sort it out.
Phil.

Hi Skynyard,
LOL, Heck even God could be wrong on the internet and no one would notice. 0:)

Here in lies the problem of one line answers to complex things.
The info was correct but only in one situation.

Lowering the value of A cap that is *in series* with
the AC signal cuts bass.

Raising the value of A cap that is *in parralell*
(i.e. across the input) with the AC signal will cut more
high frequency.

Both of these conditions refer to the AC part of a circuit and guess what???
Neither one will help in this situation because C3 is part of yet another thing in a circuit called DC condition.

It's probably better if one of the more teky ones here cover that part. I'll just confuse the issue.

Meantime just keep this little rule in your head;
To build a circuit you have to set the DC conditions of a circuit first so that the AC signal will pass through in the best possible way.
AC stuff is not so hard but DC is a little more complex,,well was for Me at least.

Cheers, Phil.

Try a lower value for C3, 22uF/25V

Try 2.2uF instead.

It's a fine line between getting great OD but by then you loose the bottom end and your sound becomes tiny and lifeless.
Phil.

Hi skynyrd,
               Yep tricky at first and does mess with the brain a bit but just keep sucking up stuff.
Oh try this page; http://www.geofex.com/article_folders/TStech/tsxfram.htm

Covers some basics that a guitar player who wishes to tinker might find helpful. 8|

Cheers, Phil.

Hi JMF,
       Sorry been busy.
Thanks for such a very kind offer but I suspect you would do it more justice.
I am only a humble hobby flux sniffer and now that I've got the Reverb I always wanted, I'm not about to embark on mass production.  :duh
(Just quitely, My Darling wife will devorce me if take on more projects). :grr

With the digital stuff now there is not as much interest in the old stuff so long as the younger ones get to see how the older teck worked they might appreciate the dedication of people such as yourself who obviously have spent years accumilating the intricate know how of building such devices.

On the surface a spring reverb might look like a simple and basic device but
Gee wizz don't try and build one over a weekend from scratch.

Saying I took 10 years to perfect a working SR unit of pro quality might look like I'm a slow learner,,, but heck it taught me so much and forced me to go read books that
I would have never otherwise bothered to read.
I was not the kind of chap to settle for a very dull sounding kit unit that was very noisey.   No I wanted a Real One. :trouble

Before finding computers and the internet there was only books and I did get
very lucky as some wonderful gentleman saw my predicament and gave me a copy of
*Art of Electonics by Horowitz &Hill*.

Wow A big help indeed but with limited understanding I found the maths very hard yakka. As a novice you just keep reading and by design and a strong desire you eventually start to grasp the more detailed stuff.

Then finally a computer arrived and again same chap handed me some circuit sims and finally the dots started to join together and I could see without even burning my fingers with hot solder (or the need of expensive test gear) just how the intricate details of each part of an amplifier worked.
So while trying to build a reverb I actually learnt how the whole amplifier worked and that is a very empowering feeling to know that with some hard work I can not only build a very good reverb I can also build Amps that will sound just as good as the expensive shop gear.

Thanks,, Phil

Oh damn forgot to mention,,, same link above.
Checkout the *Teck Talk* where Glen explains how he uses the guitar *Controls* and some simple explanations of the TW Amp as well,,,,

You just might learn some things that all players should know/ learn.

Note the comment where he shows how the clean sound is very close (In SPL) to the distorted sound.
No that is what I call ***Dynamic Response***

Phil.

I would be wanting to check what the real one sounds like before you get all glassy eyeed

Try this as example, it would seem this is the Real Deal.
http://www.myspace.com/glenkuykendall

Note the distinct sharp cutoff in the high freq dept?

Very obvious with the Les Paul.

Don't get me wrong it's a very well built nice sounding responsive SSAmp,,,
BUT To stretch that into,,, ""it's a SS TWreck"' is a massive leap of blind ignorance.
Phil.

Oh forgot to mention,
                             I built a cut down version of the Vtwin > into SS poweramp, so I know how well it works. Good but no match for a SSpreamp into a decent, well thought out Valve power stage.
Triodes can't do the Square wave trick (which is what you need).
Even when triodes are used as PP output through a transformer,, still no Cigar.
Phil.

If you are happy then it matters little but I heard a lot of blocking type distortion happening in your clip.
Of course it's hard to tell with clips.

Having also peeked at the schematic then I doubt if the tone controls are doing much.
For me personally I would be wanting more clarity from my chords but again some folks may want all the muddyness.
All just my observations.
Cheers Phil.

Hi skynyrd,
               Judging by some of your comments and your handle ,,you seek a rock to bluesy sound.
If so? Then do it the other way round if anything.
i.e. SSpreamp and Valve Power Stage.
Hi gain metal sound will benifit from lotsa preamp scream but probably not what you seek.

Triode distortion is just lots of fizz,,whereas full bore pentodes SING (partly due to the OT)
Remember that Pentodes where invented to get around the pathetic perfomance of triodes.

If you absolutly can't help yourself and you wish to go in that direction then download the Mesa Vtwin pedal ,, might give you some ideas to work with.

Have fun, Phil

Notice the use of the Word *TONE* to describe a simple metal recess ring.
Then also notice the Word *MOJO* to better describe it's scientificly proven quality.

Excuse me while I step out and throw up.
Phil.

Sadly it's not just the cheap knockoffs.

I have an old Yamaha *Professional Series* PowerAmp, 2 x 45Watts.

most of the build could pass for military grade.
The input has an equally Pro setup.
Unbalanced line in 6.5 TR and a good quality cannon Balanced input, plus a switchable low pass filter (for use with BiAmping tricks)

I've had it for years, no real issues until I had a headscratching issue with a less than ideal mixer plugged into the bal input.

Upon lifting the hood I found to my horror that the cannon had pin 1 and 3 tied
Effectively rendering the bal input a Joke. 
So much for *Pro Series* equipment.
I learnt a lot about fake balancing (dirty little tricks) from that little conundrum.
Phil.