Flo - A Second Generation EBB5 bass

[SamIAm]

After really enjoying building Twiggy I'm enbarking on a second build (Boy is this compulsive!).

 

Twiggy was a prototype made from a 2x4, she is lovely ... but a few things came up.

 

• Hey body has developed a crack.  
• I was too ... enthusiastic ... carving the neck leaving me without adequate room to safely install a truss rod and my neck relief seems to increase weekly, tuning is a nightmare!
• I did not have enough room to house the electronics.
• I've decided I want an EndurNeck™ .strandberg* style neck, By pure luck, Twiggy's is close but not quite right, albeit very comfortable ... careful use of a CAD design will assist me here.
• Pine is not unattractive, but I'm going for Maple this time, both for appearance and stability.
• I found my multiscale approach was suboptimal.

 

Lessons learned

• I can build a bass, she plays well and sounds nice (I've rotosound tru bas strings and they are gorgeous)  it's been quiet a buzz the number of folks who come up after the gig to enquire what sort of bass she is.
• Plan 5 times, cut/carve once (or even 0.2 times and repeat)
• I can get a good sound tension from a 30 B0 STRING.
• Multiscale is hard, I don't like to look at the front of the fingerboard and I find it hard to figure the fret positions from just my side markings, esp for the treble side strings.
• Not using a trussrod -> too much relief so action is too high for comfortable playing.

 

Similar to Twiggy

• 5 string fretless.
• Single piece construction
• Short scale of about 730mm
• Minimal overall length

 

Changes for Flo

• Through documentation so I can remember everything for the next build  lol
• Template based neck shape with adequate space for a truss rod.  Loosely based on the 
• Milled single aluminium string anchor at the head end.
• Finer threads on the tuners to allow for better tuning control, I mill mill the whole things and cut/die my own thread.
• Adequate width/depth in the body section to allow for embedding of electronics.
• Nice brass insert side fret markers, tho I am considering glow in the dark for dim environments.
• Battery state indicator.
• Some shape to bottom (or fold down support) to facilitate seated playing.  I love the .strandberg cutouts bu fear the weight, perhaps some cavities/cutouts will keep the weight down.
• Self mad pickup. (No idea how just yet)
• Addition of piezo pickups (No idea how just yet)
• LED based side fret markers.

 

I spoke to David Dyk of luthiersupplies.co.uk, (Thanks to @3below & @Andyjr1515 for pointing him out) what a delightful fellow!  Their production centre is only 25miles from here and I was kindly invited to view the facility and even select some wood!

 

So in the next week or so will begin the tale of Flo!

 

S'manth x

Edited August 8, 2022 by Smanth
typo corrections

[Si600]

Woo. Flo2 🍿

[3below]

Onwards and upwards   Battery indicators are a whole bundle of interesting electronics as you will discover.  It made me think of a simple alternative. Dual battery compartment with a two way switch over in the event of one running down.  My ex military Land Rover had dual fuel tanks which made me think about dual batteries.  I can not imagine the cost of filling it, or running it, if I still owned it.

 

This JFET pre-amp looks really useful (and small) and can be ordered with 10 MOhm inpout resistance for piezos.

 

https://www.ebay.co.uk/itm/272951584025?hash=item3f8d2ea519:g:-CUAAOSwoFtfBGX8

 

They also make a version ready made with jack plug etc.  In terms of bang per buck, I really rate the Joyo 504 / 505 preamps, however they are probably too big for Flo2.

Edited August 5, 2022 by 3below

[SamIAm]

3 hours ago, 3below said:

Dual battery compartment with a two way switch over in the event of one running down.

The EMG MMCS and Tone control I'm currently using thrive on 18v ... not sure I can fit 4 PP3s in the case.

 

I cannot remember where but I saw a really cool single flashing LED that sped up (I think) when the battery voltage was starting to approach a too low level, I'd love one like that!

Edited August 5, 2022 by Smanth

[Richard R]

5 minutes ago, Smanth said:

I cannot remember where but I saw a really cool single flashing LED that sped up (I think) when the battery voltage was starting to approach a too low level, I'd love one like that!

This type also doubles as a metronome/gig-saver:

When the battery starts to get low you have to play faster to ensure you finish the set before you go silent, so the flashes set the tempo. 

Edited August 5, 2022 by Richard R

[SamIAm]

2 hours ago, 3below said:

Onwards and upwards   Battery indicators are a whole bundle of interesting electronics as you will discover.  It made me think of a simple alternative. Dual battery compartment with a two way switch over in the event of one running down.  My ex military Land Rover had dual fuel tanks which made me think about dual batteries.  I can not imagine the cost of filling it, or running it, if I still owned it.

 

This JFET pre-amp looks really useful (and small) and can be ordered with 10 MOhm inpout resistance for piezos.

 

https://www.ebay.co.uk/itm/272951584025?hash=item3f8d2ea519:g:-CUAAOSwoFtfBGX8

 

They also make a version ready made with jack plug etc.  In terms of bang per buck, I really rate the Joyo 504 / 505 preamps, however they are probably too big for Flo2.

The problem (as I see it) is that each saddle will require it's own piezo pickup with the associated cost and wiring complexity ... is there a better way?

 

S'manth

[Si600]

"The best way to deal with complexity is give in to it."

 

- Oscar Wilde. (Sort of)

[3below]

2 hours ago, Smanth said:

The problem (as I see it) is that each saddle will require it's own piezo pickup with the associated cost and wiring complexity ... is there a better way?

 

S'manth

 

Adjustable bridge something like the one I made (and pretty generic) , this will give you height and radius adjustment and allows a simple rod or flexible piezo.  You have the luxury of being able to print something fancy.  You could sink it into the body, have a look at this https://www.liutaiomottola.com/instruments/libellula.htm. I have owned a fretless acoustic bass with a simple bar bridge since 1980.  The original Roto Tru Bass strings lasted 40+ years, intonation has not been an issue.

 

 

If you want individual string piezo amplification and are going down the diy route, in principle I would use two quad JFET op amps, with individual op amp buffering of each string in unity gain non inverting mode (you can get octal JFET op amps, however afaik these are surface mount so present a further complexity). These outputs would then feed into an inverting summing op amplifier to allow the individual string outputs to be equalised (through some variable resistor arrangement).  Input capacitance, consequent high pass filtering, and setting the bias voltage, depending on what your proposed voltage supply is will need to be considered.   There are plenty of good examples about to study e.g. 

 

https://www.analog.com/en/analog-dialogue/articles/avoiding-op-amp-instability-problems.html

 

and this one. the title is so understated a mere 464 pages.   https://web.mit.edu/6.101/www/reference/op_amps_everyone.pdf

 

Hopefully more experienced Electronic engineers / designers will be along who know what they are doing,  or someone knows the commercial product that will do what you want. I have seen a suitable commercial bass piezo pre amp that has individual string inputs but can't for the life of me remember what it is .  Me, I would go simple in the first instance.  If it does not work (i.e. strings too imbalanced) then look at mk3 bridge with the added complexity.

 

 

 

 

 

 

 

Edited August 5, 2022 by 3below

[SamIAm]

1 hour ago, 3below said:

 

Adjustable bridge something like the one I made (and pretty generic) , this will give you height and radius adjustment and allows a simple rod or flexible piezo.  You have the luxury of being able to print something fancy.  You could sink it into the body, have a look at this https://www.liutaiomottola.com/instruments/libellula.htm. I have owned a fretless acoustic bass with a simple bar bridge since 1980.  The original Roto Tru Bass strings lasted 40+ years, intonation has not been an issue.

 

 

If you want individual string piezo amplification and are going down the diy route, in principle I would use two quad JFET op amps, with individual op amp buffering of each string in unity gain non inverting mode (you can get octal JFET op amps, however afaik these are surface mount so present a further complexity). These outputs would then feed into an inverting summing op amplifier to allow the individual string outputs to be equalised (through some variable resistor arrangement).  Input capacitance, consequent high pass filtering, and setting the bias voltage, depending on what your proposed voltage supply is will need to be considered.   There are plenty of good examples about to study e.g. 

 

https://www.analog.com/en/analog-dialogue/articles/avoiding-op-amp-instability-problems.html

 

and this one. the title is so understated a mere 464 pages.   https://web.mit.edu/6.101/www/reference/op_amps_everyone.pdf

 

Hopefully more experienced Electronic engineers / designers will be along who know what they are doing,  or someone knows the commercial product that will do what you want. I have seen a suitable commercial bass piezo pre amp that has individual string inputs but can't for the life of me remember what it is .  Me, I would go simple in the first instance.  If it does not work (i.e. strings too imbalanced) then look at mk3 bridge with the added complexity.

 

 

 

 

 

 

 

The simple beauty of that single bridge is lovely, it would really make her so elegantly uncluttered!.  Mu Kala UBASS solid body has something similar.

with a a single piezo strip under the nut.

 

But I struggled twofold with it

 

1) For some strings it was less sensitive, often I could get no sound from my G string. I never went the route of dividing the saddle like some have

 

2) Intonation was awful and unadjustable, maybe it was my lack of playing skill as I've heard amazing sounds from a Kala, perhaps as Flo will be fretless 2.0 I can just adjust by careful finger placement.

 

I do however have a hankering to have 5 separate signals so I can build some sort of pitch to midi unit, which I gather is better addressed with each string being routed individually.

 

Why do many/most electric guitars/basses have individual string intonation adjustments?

 

S'manth x

 

 

 

[3below]

Fully understand the string balance issue, I have had to fettle several piezo guitars and basses to get reasonable results. 

 

I can see the appeal of Individual string outputs, particularly if you want to use midi. 

 

The last question probably has the easy answer, Individual string intonation gives better results than bar bridge types.

[SamIAm]

4 hours ago, 3below said:

Fully understand the string balance issue, I have had to fettle several piezo guitars and basses to get reasonable results. 

 

I can see the appeal of Individual string outputs, particularly if you want to use midi. 

 

The last question probably has the easy answer, Individual string intonation gives better results than bar bridge types.

Fettle?

[JPJ]

17 hours ago, Smanth said:

I cannot remember where but I saw a really cool single flashing LED that sped up (I think) when the battery voltage was starting to approach a too low level, I'd love one like that!

John East used to offer a battery indicator but it’s no longer listed on his website but it might be worth dropping him a message?

[Richard R]

11 minutes ago, Smanth said:

Fettle?

Adjust slightly, usually in the context of manually changing the shape of something a bit to make it fit properly. 

Pretty much the antithesis of CAD and CNC machining. 😁

Edited August 6, 2022 by Richard R
Edited for grammar.

[Richard R]

NB: Not to be confused with furtle.

[3below]

From Middle English fetlen to shape, prepare;   I did not know the origin of the word until I looked it up, it can also refer to a person's health - e.g. to be in fine fettle.   

 

In a more useful vein, the multi channel piezo pre amp https://www.bassparts.de/epages/61038859.sf/en_GB/?ObjectPath=/Shops/61038859/Products/PPX.  They also make other interesting stuff at £££.

 

 

 

[SamIAm]

On 06/08/2022 at 12:35, 3below said:

From Middle English fetlen to shape, prepare;   I did not know the origin of the word until I looked it up, it can also refer to a person's health - e.g. to be in fine fettle.   

 

In a more useful vein, the multi channel piezo pre amp https://www.bassparts.de/epages/61038859.sf/en_GB/?ObjectPath=/Shops/61038859/Products/PPX.  They also make other interesting stuff at £££.

 

 

 

Not cheap ... but looks just the ticket, thank you!!! Now to find 5 individual piezo pickups

 

S'manth

[Richard R]

Do you ever take an easy route, @Sman1992?

[SamIAm]

Flo - 8 August 2022

 

So a few things occurred today.

 

Battery Life Indicator

I'd emailed John East, who said he may have one still lying in the dark recesses of his stock (My words not his) so I may luck out.

Failing that, I found a circuit for something that looks like it would do the job.

https://www.homemade-circuits.com/low-battery-indicator-circuit-using-two/

It claims just a 1.5mA drain so not too shabby.

 

Side Fret Markers

I've decided to use LEDs as the side dots for fret markers, a set of Neopixel type LEDs and a small microcontroller will let me change brightness and colour as desired ... just need to throw together a circuit.  Power draw is not too high but I'll likely run it from a seperate battery so as not to get any chance of crosstalk with the signal chain.

 

And the best till last ...

David Dyke & Team - luthiersuppliers.co.uk

I Spoke with David last week about getting some wood, what a lovely chap!  In our discussion it transpired they are based just 25 miles from where I live and David generously invited me down to see the workshop and pick my wood.

 

So this morning I had a drive through the lovely East Sussex countryside.

I was struck firstly by the delightful smell of the lovely gardens surrounding the hall and then blown away by the gorgeous aroma of all the wood, all of it treated so as to be ready for building instruments.

The beauty of the workshop was breathtaking.

 

David himself planed my block of maple down to make things a bit easier for me.

 

And I received much (much) advice about trussrods, carbon rods and general knowledge from the team of expert luthiers.

 

Everyone was so welcoming and knowledgable and the workshop was an Aladdin's cave of exquisite-ness.

Without a doubt I shall be returning if (Well, probably when!) I make my next instrument ... I cannot recommend them too highly!

 

And the goodies I came away with ...

• Maple Core for neck/body.
• Dual action trussrod
• Two 4x4mm carbon fibre rods
• Two sections of beautifully contrasting wood for the skunk stripes for the trussrod & carbon rods
• A combination bottom strap pin/jack (Not pictured)

 

 

Next step is meticulous planning and construction of templates along with many questions about the best order to tackle construction.

 

S'manth x

 

(Permission was given to capture images for my build diary)

 

[3below]

A good trip out .  If you are going to use a microcontroller with the marker LEDs you could use a simple potential divider and a GPIO with ADC  to determine low battery voltage.  There are also various Arduino ready made voltage sensor modules available very cheaply.

[SamIAm]

8 minutes ago, 3below said:

A good trip out .  If you are going to use a microcontroller with the marker LEDs you could use a simple potential divider and a GPIO with ADC  to determine low battery voltage.  There are also various Arduino ready made voltage sensor modules available very cheaply.

Great thinking!

 

I use a M5Stamp C3U Mate (Which is very small. has a really low power drain and is very cheap). 

https://thepihut.com/products/m5stack-m5stamp-c3u-mate-with-pin-headers

 

I could even use the LED dot markers to indicate the power level so very hard to miss ... hmmm

 

S'manth x

 

[3below]

38 minutes ago, Smanth said:

Great thinking!

 

I use a M5Stamp C3U Mate (Which is very small. has a really low power drain and is very cheap). 

https://thepihut.com/products/m5stack-m5stamp-c3u-mate-with-pin-headers

 

I could even use the LED dot markers to indicate the power level so very hard to miss ... hmmm

 

S'manth x

 

That is a genius idea (and once mentioned is obvious).  I like it  I also like your UC choice, my time has also recently been focussed on ESP32 with WiFi and BT.

Edited August 8, 2022 by 3below

[MoonBassAlpha]

The spec says it draws 500mA @5V, sounds rather thirsty for a battery powered application,  no?

[3below]

Missed that, however turning off unwanted peripherals:  wifi, BT, lowering clock frequency and using a single core will have a substantial effect on current draw.  some data here gives an indication:  https://www.mischianti.org/2021/03/06/esp32-practical-power-saving-manage-wifi-and-cpu-1/.  At 10Mhz cpu frequency (more than adequate to control leds and make sample voltage measurements) the current draw is about 13.2 mA.  In reality it will be higher even before the LEDs and potential divider currents are factored in.   These could be switched e.g. > 60hz with LEDs, battery sampled every 10 mins? 5 mins? 

Edited August 13, 2022 by 3below

[SmanthTemp]

Flo is no longer going to be ... roll on Phoenix  - A second generation EBB5 bass, you'll understand shortly.

 

This is S'manth, at present I am unable to access my 'real' account for reasons that will soon become clear, as will sadly why Flo is never going to be built.

 

https://www.moreradio.online/news/sussex-news/hove-fire-one-rescued-from-fourth-floor-flat/

 

I awoke late evening (Not long before Midnight on Tuesday) to a strange smell, like burning toast .... but I hadn't made any toast (or cooked anything earlier).  I ignored it for half a minute but it seemed to be getting stronger ... so I got up out of bed ... perhaps Kitty Kitty had been up to some mischievous.

 

Immediately my head was immersed in the most opaque, hot, acrid smoke I have ever experienced!  Something not quite right here!

 

I managed to make my my way out of my bedroom, towards the front door (Internal door of my 4th floor flat) where the heat and smoke was worse.  My lights would not switch on, I was gasping and coughing  and terrified.  After what seemed hours (but was probably just half a minute) I managed to open the door and stagger out into the communal upstairs hallway ... another minute and I would not be typing this (Or doing anything indeed!)

 

4 flats on each of the 5 levels, I started pounding on doors and screaming fire, I suspect that more people were traumatised by the sight of this nearly naked frantic woman with blackened face and crazy hair then by what I said ... but over the next couple of minutes, as more people awoke some sort of order set in and the block was cleared; then the two adjacent.  The emergency services responded fairly quickly and performed their heroic activities.

 

Myself and one of my 4th floor neighbours were blue lighted to the local hospital for assessment of smoke inhalation, thankfully we're both physically OK.  Emotionally (for myself ... totally different matter)

 

Some of the images ...

 

The next day after my dearest friend came to collect my from Hospital, we stopped by the block to see what we could find out (She has the spare keys to my flat) most of the flats looked OK, people were back in ... even my immediate neighbour seemed to have returned home.

 

A police officer stopped us on our way up the stairs saying that my flat was still being investigated and entry was not allowed, but was gracious enough to snap a couple of pix on my friends phone.

 

When I saw them the small hope I had melted away, pictured is my front entrance/hall/living room.  All of my music making stuff was in the Living room including the lovely wood I had just got to build Flo ... but a picture is worth a thousand words so ...

 

The local council have been amazing and managed to get me into emergency housing for the weekend and we shall see what happens next week.

 

The main takeaways ...

I am alive.

None of the neighbours were seriously injured.

And I have hope that Kitty Kiyyt was able to escape and is currently sipping some lovely milk with a kind person.

 

Normal service will resume ... at some point!

 

In the meantime PLEASE make sure you have smoke detectors installed that work and have at least two ways of exiting your home (Oh ... and keep your important documents in a fire resistant box lol)

 

S'manth x

 

 

[blisters on my fingers]

What a terrible ordeal for you and your neighbours

Hope Kitty is ok