Freedom day

Fulô, the trimaran, on the 25th April 2013 club race

One more weekend at the mooring...

Stormy weather has been keeping us tied down for much too long...

My feet are beginning to grow roots from being ashore...

This weekend was no exception...

Cheers

Pedro

Vox Pathfinder 10 mod pack

Here are the mods I've implemented to my Vox PAthfinder 10

PROCEED AT YOUR OWN RISK AND KEEP IN MIND THAT EVEN LITTLE AMP'S CIRCUITRY CAN CARRY LETHAL VOLTAGES. IF YOU'RE NOT FAMILIAR IN DEALING WITH SUCH CIRCUITS LEAVE THE MODS TO SOMEONE COMPETENT TO IMPLEMENT THEM.

1- External speaker jack
2- More powerfull power transformer. The unrated original unit (probably 1A) was replaced by a  2A transformer.
3- Original 14W TDA2030 chipamp replaced by a 20W LM1875 
4- Original distortion circuit's red LEDs replaced by 1n34A germanium diodes
5- Original OPAMPS replaced by JRC4558DD mounted on sockets for chip swapping on the go.

The Pathifinder 10 is a great little practice amplifier that you'll find to be a wolf in sheeps clothing...
The miniature stock speaker does not make justice to the circuit's capabilities and you won't help a very sincere WTF! when you first listen to this little box roar through a proper 12 inch driver. So the first and most cost effective mod is the external speaker jack socket.
Mine is wired in the usual fashion in such cases: Using a switched jack. Whenever an external speaker in connected to the jack, the onboard driver is shut off (thankfully).


As for the electronic mods the changes are somewhat less noticeable, nevertheless very rewarding:

- The 4558s rounded things of a little bit in what concearns the high frequencies;
- The distortion is smoother after the replacement of the original red leds by 1N34A germaniums in the clipping circuit;
- At max output there may be an increase in undistorted sound volume, courtesy of the higher capacity transformer and LM1875 chip in place of the original TDA2030 and tiny transformer.

Although this may be just my ears playing me I've had very good previous experiences in Hi-Fi DIY with the 1875 and the general opinion out thereregards the 1875 as a generaly "better" chip than the 2030, being more dynamically responsive


More on this work in progress later

Regards!

DIY Optical Tremolo

In the course of this crappy winter for sailing I have to limit my past-time activities to electronics.

After many experiments arround the subject of optical, LDR based, tremolo for guitar I decided to go ahead with the concept of a rotating disc unit. I tend to always prefer electromechanical devices in opposition to purely electric/electronic gadgetry...

Still on the breadboard, I allready found myself face-to-face with the issue that I was more afraid of: DC noise from the motor making it to the audio signal...

So, plenty to reseach and test for the time being. I'll keep posting developments...

Meanwhile here's a picture of the prototype array and respective schematic.

Note the addition of my own do-it-all mighty clean booster. Tremolos don't have to decrease overall output by definition do they?


Next to include:

1- Eliminate DC motor noise issue
2- Depth adjustment: A pot in series with the led
3- Tru bypass switching

See you!

Project '13

New year, new project...

Work in progress as of yet:


http://soundcloud.com/pedro_cabral/segunda-demo1 

http://soundcloud.com/pedro_cabral/primeira-demo1

Ashore

The mighty "Azul" (Blue) is ashore for general maintenance and to repair of a minor crack in the hull.

Azul is a Philippe Harlé Gros Plant (a minitransat 6.5m) built by my dad. She's been sailing arround Alhandra for about ten years now:

http://fr.wikipedia.org/wiki/Philippe_Harl%C3%A9 
http://www.pzsc.org.uk/history/minitransat/index.html

Arsénio Novo Tube Sound Overdrive

Oh no, another solid state circuit claiming to sound like a tube based one...Well, as you'll find out on your own, this time it's true.

Following a very convincing recomendation from a friend and some positive criticism at the forums out there about this amazing little circuit I finally decided to give it a go.

I never liked the onboard distortions of any of the amplifiers I've owned over time* and I've been in the search for quite a while now for the perfect distortion stompbox to go somewhere in between my tube fueled Guyatone FLIPVALVE PD1 Power Drive and my Guyatone SD2 Sustainer D. Well, I guess the search has ended.

*A cheap Legend 15, a not so cheap but indeed VERY unreliable Rocktron Rampage R80, a massive Crate GX212, a Vox Pathfinder 10, a Fender Champion 600 and a Roland Cube 40

Has it happens this awkward "back to back" PNP-NPN arrangement is likely to be the more juicy distortion you'll ever ear from a solid state distortion ciruit. I'm still trying to force myself to believe that a parts count as low as this can supply the goods in such a competent manner...

Here's the circuit:

P2 being a trimpot to help set the bias (should be set at half, approximetely, or wherever you find the best sound) and P1 being the output level control. No gain, no tone, no complication. The guitar controls are very effective in controling the behaviour of the circuit, as I'm sure you'll have a chance to confirm by yourself. Also, nevermind the switches. Those are there as a part of my own experimentation.

To ease your troubled minds, yes, I've tried a FET buffered input. I didn't like what it made to the sound though, but you're of course  free to go ahead and try one for yourself!

Here's the TINA-TI simulator simulation (@0.25Vpp/1000Hz input)

Instead of a written description of the sound (which would never make justice to the A.N.T.S.O.D) I thought it might be best to record a demo, so here's the soundclip:

https://soundcloud.com/pedro_cabral/antsod-sound-sample

Recorded using the following soundchain: Yamaha Pac311 (Fender Noisless e Gibson PUs) -> ANTSOD -> Roland Cube 40 (line out) ->PC

I've also made your rookie DIYer's life a bit easier by compiling a stripboard layout of this pearl:

Here's the almost finished product, in a very nice aluminium box available in Portugal at: http://www.sonigate.com/pt/product/show_details/58502/Caixa-Aluminio-115x65x35mm

Also of great interest is the descriptive memory of the circuit (dated back to '95) by the man himself:

From: Arsenio Novo
Date: 04 Jul 95 23:04:50 
Newsgroups: rec.music.makers.guitar
Subject: New Overdrive Circuit

Hi,

I've noted that talk on this echo always comes back to the subject of
overdrive distortion. Whether generated by a vacuum tube amplifier or
a transistor amplifier there seems to be undeniable differences to me
as well.

Lately, I was tinkering with an unusual transistor circuit
configuration I had come upon a few years ago and made a few
modifications to the circuit that turned it into one beautiful
screaming "tube-like" overdrive but without the wall of noise these
things usually make. When pushed it even makes that distintive
"zoo-zoo" sound...!!!

The original circuit was simply a complementary matched pair of
transistors connected so that all the terminals overlapped. i.e. both
bases tied together, emitter of the PNP connected to the collector of
the NPN, and the collector of the PNP connected to the emitter of the
NPN. Thus:


This transistor pair is then biased by 2 equal value resistors in each
of the compound legs, one to the positive supply and the other to
ground common. The signal is coupled to the base pair leg and the
output is picked off either of the other 2 legs.

The result is that the above circuit exhibits the behaviour of a
multiplier over a range of signal values. It basically performs a
sin function: in other words a frequency doubler.

This doesn't have a very good distortion sound though because it is
rather "burpy and buzzy". However, lately I was toying with the
circuit when I offhandedly decided to try doing something to it just
to see what would result.

After adding a large cap from the NPN's emitter to ground the thing
went wild on me... WANGO ZE TANGO! SUPREMO DISTORTION! I then
proceeded to refine the circuit a little more and got a better
understanding of what it was doing.

The final schematic follows but first a couple of notes on the
circuit. The "bias balance" trimmer should be adjusted for a
symetrical clipping threshold of the output signal as viewed on a
scope. Short of this it can be easily set by "ear" for the most
sensitivity somewhere around mid-turn.

The input should be driven by a lo-z stage if your electric guitar
doesn't have a built-in pre-amp. You can alter the emitter capacitor
value in a range from 0.1uF to 1uF in order to obtain various basement
characteristics but I found the indicated value is a good compromise.
The input capacitor should not vary much either though because if it
is made too large the circuit goes balistic and cuts out on the tutti.


"Tube-sound" Distortion Overdrive Circuit:


The operation of the circuit more closely resembles a vacuum tube than
a diode clipper does because of the strong square law characteristic.
This is due to the negative feedback around both base-emitter pairs.
This feedback accentuates the junction non-linear behaviour manyfold.

Thus each transitor drives the other even harder so that the transfer
curve ends up more logarithmic than is typical of a single transistor.
In other words: the clipping is gradual and not abrupt like it is in
the case of a silicon diode. Typically a lot more 2nd harmonic is
produced as well. As a bonus the waveform folds over on itself when
the circuit is overdriven!

Now in the interest of the common good I donate this design to the
public domain for personal use but retain copyright and reserve all
rights for any commercial purpose. In other words build one for you
and your friend but if you have it massed produced for profit I only
ask a fair share.

Please, do try the circuit and leave any comments in private at my
e-mail address: arsenioDOTnovoATmbaDOTorg

By the way, does anyone know who's Arsénio Novo? I'd like to thank him...

Have fun!

Pedro

Regata Belém-Alhandra-Belém

Nem só de trabalho, estudo e afazeres terráqueos me governo...De vez em quando é preciso ir à água...

A chegar a Lisboa de manhã bem cedo.

 Um pouco antes da Vasco da Gama

 A passar Alverca, já depois de acabar a regata (que foi encurtada na baliza 1A)

Idem

 A caminho de Alhandra com a Nau dos Corvos e o Nichu's

Alhandra à Vela

Há dias que, em Alhandra, a gente se se lembra daquilo para que servem os barcos à Vela...

Oxalá se repitam estes dias, por muitas e muitas vezes...

A DIY footswitch for a Roland CUBE

A couple of months ago I bought myself a Roland CUBE 40XL as a stand-by amp for when a gig shows up.

http://www.roland.com/products/en/CUBE-40XL/


I really like the amp (especially the clean sound) and think it is as close as reasonably perfect an amp should be:

-Fair price (paid 197€ new); 
-Great sound;
-Two (or more) channels
-Predictably reliable and low maintenance (if any)
-Speaker/Amp-Emulated recording/phones output
-Inconspicuous looks;
-Strudy build quality;
-No-nonsense features;
-Loud, and remains clean while loud (if you want it to);
...

It could benefit from a line-out and external speaker jack (the bigger 80W brother in the line has it!), but hey...For the places where I intend to play I guess these features won't be needed anyway...

The shock came in the time of buying a footswitch... 60€ average price for a Roland FS6 and 30€ for the equivalent Behringer clone? Now, that's expensive... Has anyone explained these people that foostswitches are nothing but, well, switches?


While the use of such gadget is not absolutely necessary for one to enjoy all the features of this amplifier,it sure comes in handy and is highly recommended to explore the built-in 80 second looper at its full capabilities (except for those who have 3 hands)..


But then again: 30 to 60 € for a pair of non latching push buttons ?!?!?

No way, not for my daddy's son...So I came up with this:

Not pretty but, as usual, does the trick...

BOM:

2 x momentary push buttons (the more sturdy the better)
1 x scrap plastic box (this one is from an old printer's PSU)
1 x piece of 3 conductor wire (this one I made myself by twisting 3 pieces of identical wire using a hand drill)
1 x stereo jack

CIRCUIT: (really simple)

Hope you find any use in this and remember: The quality of any of your DIY builds is only as high as that of the worse component you put into it...

Cheers!

Pedro

AFTER NOTE: The footswitch will work better if you use normally closed switches. The effects and channel switching will work anyway, but the looper function will only work properly with the switches in normally closed state.

Insólitos Gibson

A Gibson sempre foi uma marca de que me causou um bocado de aversão pela prepotência com que inflaciona os preços dos seus instrumentos FABRICADOS EM SÉRIE, como se mais não houvesse no mundo quem soubesse fazer guitarras, mas esta é demais:

http://store.gibson.com/historic-spec-bumble-bee-capacitors-two-pack/

2 condensadores falsificados (como se mostra aqui http://www.mylespaul.com/forums/historics-reissues/118027-historic-gibson-faux-bumblebee-caps.html) por $133 ???

Vergonha...Afinal muitos dos grandes até tocam com Stratocasters...

New guitar, new songs...

New guitar:

http://otrimaran.blogspot.pt/2012/05/pedro-cabral-serial-005.html

New songs:

http://soundcloud.com/pedro_cabral/feeling-empty

The Anti-Behringer syndrome

Honestly, doesn't it seem that Behringer's competitors are paying people to sign in at home recording forums with the sole purpose of providing generous ammounts of desctructive criticism and deception to all happy Behringer users out there?

I mean, why else on earth would there be so many people disencouraging others to buy good and cheap stuff? Trying to prevent other folks from having endless hours of fun making their own music with a complete studio setup gathered for little more (and often way less) money than a single piece of more appraised brands's equipment.

I've been an avid consumer of Behringer's products for as long as I can remember myself trying to make music and I honestly have little but good things to say from their products.

In what concerns the German brand, my PC based home studio is currently equipped with:

-Several Behringer guitar stompboxes, including a tuner
-A UB502 mixer
-A C3 condenser mic
-A MIC800 microphone pre-amp/phantom power source
-A UCA202 USB audio interface
-More recently a V-AMP 3 and the UCA222 that came along with it

All this can be put together with a few hundred € or so and, from my searches, I cannot find another single manufacturer capable of  even coming close to supply good sounding material at  prices such as Behringer's. In addition to this, Behringer also keeps a very good support site with links to what seems like an endless amount of  manuals and software to get things going.

Recently I've bought a V-AMP3 (new from the store for 54€) and, while searching for reviews before buying, I was amazed by the insane spread of Anti-Behringer syndrome raging all over some of the home-recording forums out there. Reminded me of the ridiculous antipathy Americans (used to?) have for foreign cars (even though they often cost less, are safer, drive faster, burn less fuel and outlast their "bigger and heavier is better" national products). Here are some of the more oftenly used arguments:

"Plastic made"- Disregarding environmental considerations, I can't see how this can be a bad thing. Plastic is lighter, cheaper and not necessarily less reliable than metal for a given application. Lots of things have EVOLVED from metal to plastic through the years and this does not seem to be a bad thing in any other industry other than music's. Are your TVs at home made from steel? Is your cell phone die cast? Would they last longer if they were?

"Bad sounding"-Well, I'm happy that so many other home recorders are wealthy  enough to have their bedrooms stuffed with the finest grades of snake's grease. On my side I prefer to have the so called"bad sounding material" but have SOME material to make my music, while being honest enough to admit that the REAL limitation to my sound is not in my Behringer gear but in my mediocre skills as a singer and guitar player. Plus, what's the point in having audiophile grade gear to record stuff that is to be compressed in to MP3 and delivered as crappy audio streams through MySpace or, worse, burnt down at 16x speed in cheap CDs.

"Unmanageable latency on UCA202 and 222"- This is utterly false. Make sure you have Behringer's correct ASIO drivers installed (available free from their site) and make sure you have your recording software set to operate with them. Are you familiar with the Options tab of your multitracker? If not then Behringer is not to blame.

"Unreliable construction"- In more than 10 years of using their equipment I'm still to experience a fault, but then again, I'm not keen to mishandling my so hardly gathered stuff. Buttons are to be pressed, not hit, and stomp-boxes are to be stepped on, not kicked arround. In a similar fashion, pots are built to be used as pots, not as levers or feet rests.

"Everything that says Behringer has no place in anyone's studio"- Well, such arrogance speaks for itself... No comments needed, really...


I remember, when I started sailing, of the very few who were able to afford heavy weather gear. Douglas Gill, Aigle, Helly-Hansen and a few others where the only available clothing brands and you'd have to be a minister's or bank robber's son to sail in the winter without freezing to numbness. The rest of us had to live with wool clothing, Kispo jackets and landlubber rubber boots. Then along came Decathlon, with the Tribord range and confort was made available to the masses. Everyone could now buy a full equipment for 100€, which weren't even enough for a pair of Aigle sailing boots. The reaction of the sailing community was similar to the Anti-Behringer Syndrome: Decathlon's gear was rubbish. Why? Well, maybe because they were just  plain envious of all us poor old up-river chaps finally being able to sail along (and often ahead) of them under all the weather the sky  and sea could think of throwing at us...

As a friend of mine (who is presently sailing the world all alone) said to me the other day: "What's the point in having a Rolex if a quartz Casio does just about the same?"

It's your choice...You can spend the rest of your life chasing rainbows and dreaming about the so-called "high-end" gear you'll never have or you can be honest with yourself and be conscious of your real needs and start recording next month in a fully equipped home studio built from end to end with Behringer's gear... Don't believe it? Check it out:


http://soundcloud.com/pedro_cabral
http://www.myspace.com/pedro-cabral



Thanks Behringer!


Cheers!

A few more pics from the most beautiful boat of Alhandra and, therefore, of the world

Courtesy of Bigareta's crew, Fulô near Vasco da Gama Bridge, on our way to the Tall Ships Race start in Lisbon

Heavy weather...

After 22 years of sailing in Alhandra I'd never seen myself in such a mess... 12 miles under strong winds, high and tight river waves and a useless motor hanging out the stern was what we had against us yesterday evening returning from a sight seeing trip to Lisbon to watch the Tall Ships Race start...

On the way down everything was fine and I even took some pictures, on the return trip, well, things got a little bit complicated and there was no time for pics...

Lessons learned? Plenty:

1- I really need to solve the motor aeration issue (probably by lowering its mount even further);
2- I need a smaller weather jib (or a reef in the current one)
3- I need another reef in the main

But mainly:

4- I need to learn to trust my instincts better than on Windguru's...

Cheers!

Twisted panoramics

Fulô, the mighty Piver Nugget from Portugal, here on some wicked photo stitches...

 

Another sourceforge marvel: http://hugin.sourceforge.net/

Another sailing weekend (out of the very few I've been able to enjoy this year)

This year I've decided to celebrate my birthday in the best way possible: Sailing upriver Tejo.

Underwater traps for thin hulls (such as ours) entering Valada. These steel pipes are used to anchor fishing nets:

A grounded willow tree log in Valada:

Figaro Six "Oceanus" entering Valada under power

First mate Neil resting in the shade

Folk boat "Castro Junior" leaving Valada

Fulô, anchored close to shore:

A couple of friends in a romantic cruise in Fulô's dinghy:

Long exposure shot of the moon. Saturday night in Valada

Another long exposure picture

1st July morning. HAPPY BIRTHDAY TO ME!