Dave's Custom Amp - None More Black! Updated: Thursday 8th March 2012

THIS AMP IS NOW FINISHED!

Well here is a little something i'm putting together for a friend of a friend!

So far all the pcbs are populated and the chassis & headshell are in which I am going to prepare for the final build steps this weekend.

The transformers should hopefully be here in the middle of next week.

The spec is as follows

50w
Sprague Orange Drops
Vishay CCF60/ Koa Speer & Panasonic Resistors
Sprague Atom, F&T, Nichicon Muse Electrolytics
Onetics Hi Def Output Transformer
Onetics Custom Power Transformer
Onetics 5H Choke
SLO style Chassis & Headshell - none more black.

And here are a few pictures of whats been done so far.

Resistors Populated Vishay CCF60 1% MF for ultra quiet operation.

Panasonic Power Resistors.

Full preamp resistor population shot.

F&T Electrolytic Capacitors added

Sprague Orange Drop 715p/225p Capacitors

Sprague Atom Electrolytic Capacitor

This one is pretty much the entire preamp populated

Power amp Using Nichicon Muse Series Electrolytics & UF5408 Diodes

Vactec VTL5C1 Optocouplers for Silent & Instantaneous channel switching

Recton DB101 Bridge Rectifier for the channel switching voltage rectification

The Headshell when it arrived

This headshell needs a little adjustment. The front grill sits about 11mm too far forward.

 

And that is all for now. I shall update this post as and when things happen which should be a fair amount over the coming week.

Update: Sunday 19th February

I started work drilling the chassis today should hopefully get the amp finished by the end of the week.

This one is a fairly boring update as not much went on as this part takes quite some time as I countersunk the holes by hand as I find it a lot easier to do it accurately this way.

The reason for countersinking all the board mounting holes is so that the transformers can sit flush against the chassis.

Transformer Drilling #1

Transformer Drilling #2

Update: Friday 24th February
I managed to get a good amount done today, the amp is mainly wired up im just waiting on the preamp & power amp valve sockets as the ones I had didn't quite fit the chassis or they were the wrong pin orientation for how I wanted to do the wiring.

All that's left to do now is wire up all the heaters/valve sockets and wiring the actual circuitry in.

The Pot Shot!

Faux Center Tap

Lamp Wiring #1

Lamp Wiring Close Up #1

Lamp Wiring Close Up #2

Clean/Crunch & Bright Switch Wiring. This part needs redoing.

Pot Wiring

 Transformers Mounted

Clean/ Crunch, Bright & Channel Switches

Power, Standby Switches & Lamp

Onetics Power Transformer Hookup Schematic 

Power Amp Wiring

Preamp Wiring #1

Preamp Wiring #2 In this photo you can also see a wire joining to the preamp PCB mounting post this is coming from an RF cap that is just an extra measure that I was made aware of by my co blogger Bob that just stops those annoying radio frequencies that can sometimes be picked up by guitar cables.

Pot Wiring & Effects Loop

 

Test Run #1

Final Assembly 

 Front Right. You can see in this picture that the front panel now perfectly lines up with the front of the chassis.

Rear Right 

Signature 

This one is just for the sake of it really. These two amps are practically the same circuit wise the main differences being mine (the white one) is running on JJ E34L and Daves is running on JJ 6l6GC so it's kinda the evil twin scenario!

And here is the final shot of the amp in my posession where it went through around 8 hours of constant play testing at a range of volumes (which my gerbils weren't too happy about when it got higher)

 

Dave is coming to pick up the amp this evening after a 6 hour tattooing session and is extremely excited.

Modded High Gain Soldano Style Preamp Complete

This is just a very quick update which also ties in with my new soldering iron that I got as a christmas present.

So first things first here is the new iron. It's a pretty simple 48w temperature controlled soldering iron that goes up to 430°C in 1 or 10° steps.

Now as for the amplifier heres the progress that i've made so far.

It's been populated with Vishay CCF60 high temp low tolerance resistors. These are ideal for this kind of circuit as they have a 1% tolerance and are a metal film type so they really help keep the noise floor in high gain circuits down. Also note the Panasonic power resistors, this is my first time using these but they were spec'd right and were a better price than the Xicons that I have used in the past that were on backorder.

The coupling capacitors are Mallory 150 series polyester film capacitors. These are very high quality and are a perfect balance between all that vintage mojo you hear about from the traditional mustard caps and also the clarity and edge of the Sprague Orange Drops.

The electrolytics are a mixture of Sprague Atoms & F&T axials. These are all very well spec'd and are a perfect match for the SLO circuit.

I shall be starting on the poweramp tomorrow hopefully and will also give a breakdown of that.

Merry christmas to all and if I don't post again before then I hope you have a great new year.

Heavily Modified New SloClone Build

Well this started out as something else but has quickly taken a different direction due to a request.

The plan so far is to use Mallory 150 series for coupling/decoupling alongside F&T & Sprague electrolytics in the preamp with Nichicon & United Chemi Con Electrolytics in the power amp.

Voicing wise this is going to be a bit of a departure from the stock SLO voicing in that it's going to have an overall tighter feel with a fair bit of grit & grindiness in the midrange and I also plan on making the gain a but more aggressive also.

I've ordered all the electronics & hardware in and i'm discussing the chassis & headshell cosmetics currently.

Here is a picture of the SmashGuitars PCB's that I will be using in this build.

I shall update the blog with more info on this as the project progresses.

The headshell is here!

Well now this amp is well and truly finished.

The O'netics are here!!!

Well they are finally here after many issues and delays I can finally get this thing going.

They have a little cosmetic damage and it seems the couriers have dropped the package at some point as one of the fixing plates is bent upwards but hopefully the transformers themselves should still be fine.