Twiggy - An EBB5 bass prototype

[Andyjr1515]

Remarkable.  Speechless (a first)

[SamIAm]

I've been quite busy hence the long gap since my last update. As well as starting back clinically at work (Bedside critical care nurse) the band I'm in are doing our first performances since covid changed our world ... this has meant loads of practicing (I'm not all that experienced so for me it is simple stuff I need to get right ... and I will be gigging with twiggy so I'm getting used to a 5 string fretless) but also offered me a power challenge!

 

I've taken to using a Helix Stomp with an Ashdown Ant, lovely sound but it ties me to mains power (Or a too costly battery/inverter combo).  We are going to "entertain the troops" getting ready for a Pride march next week and we have a b'day party garden gig at the end of July ... for both, the presence of mains power is doubtful.

So I did some research and have built, printed a case for and assembled a multi-effects device (I call it effectlåda) that runs off a USB power brick ... measurements so far indicate I should get about 10h out of it on a single charge; my first Amp was a Roland Micro Bass (now glad I didn't sell it!) which can run of batteries also so I'm now good for power, and for our setup it should be plenty loud enough.

 

An added bonus (That I have been trying to implement for a while) is the ability to playback simple drum backing to some of our songs, in fact I can plug in my USB midi keyboard and select from a wide range of synth plugins (FluidSynth soundfont based/DX7/DX10/Etc) ... effectlåda runs patchbox os on a Raspberry pi, this offers a slightly modified version of the Moddevices software (Tho a couple of versions older and not as powerful) ... the audio quality is not quite on a par with my Stomp and the tuners I've found so far for the system are rather crap but the combo of effectlåda and micro bass will do the job nicely for our gigs.

 

 

Despite all this I've still made some progress with twiggy.

 

I've now put a set of Rotosound tru bass black tape wound strings (60-135) on her and OMG ... they sound glorious!  I had a bit of a disaster as my "head" mounting system started to fail; I had to redesign/rebuild it ... I was very fortunate to be able to do this without sacrificing the strings ... phew!  Once I've figured out how to capture audio with the effectlåda, I'll post some recordings up.

 

 

I've also modified the way I mounted the saddles, cutting slots to hold them (used my baby CNC machine, which did a great job).

 

This has had the dual benefit of lowering my saddle action and also much reduced the risk of a saddle slipping out and getting lost.

 

I'm now starting to get concerned about twiggy's neck stability, I might try to install a truss rod but I think I may have made the neck too thin at the head end to give me sufficient depth ... but I am now starting to look at moving onto Flo proper.  Given my experience with twiggy I feel that a B0 scale length of 780mm works well for me and whilst twiggy is a couple of inches longer than I had intended for Flo, I will probably use a very similar layout for Flo, but with higher quality wood and most likely off the shelf tuners.  I've reconsidered my earlier idea of using a pulley system to take the tuners to the rear (Both shortening the length overall and allowing me to hide the tuners); twiggy is really nice and light but dows not sit easily on my knee and there is nowhere to rest my (R) forearm ... I'm pondering giving Flo a body shape like twiggy's but adding in a fold out stand (Like the Steinberger Spirit) or implement the ability to affix a "body expander", bolting it to the rear of the "body" section of Flo ... this could be wood or even 3D printed.

 

S'manth x

 

[3below]

Really like the 'bridge' slots.  Knee rests, I remember seeing a rather nifty design for a radical minimal guitar design which I can not find now:(.   Think of the following -(  rotated 90 degrees. 

[SpondonBassed]

Excellent work.

[SamIAm]

We (The band I'm in) had our first recent 'outing' on Sat, we played open air to entertain the folks waiting for the start of the Pride march in Worthing.  It was a beautiful day and the crowd seemed to enjoy it (perhaps almost as much as we did!).

 

I became aware of a few things:

 

1) twiggy is light, wonderfully so!  I took Ponty (My shop bought 4 str short scale) along 'just in case' as this was twiggy's first outing ... didn't need him, but I realised how much heavier he is than twiggy ... I've a bad back so it was a blessing.  Flo will probably be a bit heavier as I'll be using harder wood, with a similar design to twiggy, tho the 'body' will be a few cm wider and thicker to allow me to house the electronics fully in the wood.

 

2) My battery powered Roland Micro Bass Cube cannot compete with any noise, I had it cranked up to 11 (with my effects box gain up to pre-distortion levels) and even then the band member at the other end of the lineup could not hear me!  I took advantage of the recent Prime Day sale and just received a small inverter and lithium battery so I can use my more powerful Ant + Mighty Mini combo for our next gig (We might even have power there)

 

3) The 'grab the ball end of the strings' mechanism on my tuners are failing ... the stress is just too much for the Nylon 3D printed parts.  As a result I was struggling to keep my D2 in tune; one advantage of a fretless was I could make an allowance for it in my finger positioning but still ...

 

So I set out to replace them; I decided to go for Aluminium replacements ... I bought a small block of stock and after a bit of CADding I fired up Xena.

Even at the mildest of cutting depths, this task is wavering around the upper limits of what she is capable of ... so I decided to finish them off by hand.

 

 

I must say, it was not a great finishing job I managed, but they work and seem very solid.

 

I've redesigned them to be fully CNC'd next time and sometime over the next week or so I'll pop into the MakerSpace where we have a more robust CNC machine and then they'll look quite nice.

 

S'manth x

 

PS, this is us finishing our set after the march participants departed, you can make out the tones of twiggy!

 

 

 

Edited July 14, 2022 by Smanth
pesky typo

[tauzero]

On 03/07/2022 at 20:12, Smanth said:

So I did some research and have built, printed a case for and assembled a multi-effects device (I call it effectlåda) that runs off a USB power brick ... measurements so far indicate I should get about 10h out of it on a single charge; my first Amp was a Roland Micro Bass (now glad I didn't sell it!) which can run of batteries also so I'm now good for power, and for our setup it should be plenty loud enough.

 

An added bonus (That I have been trying to implement for a while) is the ability to playback simple drum backing to some of our songs, in fact I can plug in my USB midi keyboard and select from a wide range of synth plugins (FluidSynth soundfont based/DX7/DX10/Etc) ... effectlåda runs patchbox os on a Raspberry pi, this offers a slightly modified version of the Moddevices software (Tho a couple of versions older and not as powerful) ... the audio quality is not quite on a par with my Stomp and the tuners I've found so far for the system are rather crap but the combo of effectlåda and micro bass will do the job nicely for our gigs.

 

I meant to ask about effectlåda - what sound card are you using on the Pi 4, and how are you controlling it? And evidently we both evaluated our keyboard needs identically, I have exactly the same Akai MPK mini (and in red too!).

[MoonBassAlpha]

I've always thought it would be a nice idea to have the tuner knobs with a larger diameter knurled section and smaller boss for ease of turning (better torque) and reversing the orientation for alternate strings. I'm surprised no one has tried this yet, AFAIK anyway!