So I used svg to manage creating this shape:

function tie(pitch: Pitch, octave: Octave, x1: number, x2: number) {


  let make_mask_id = 'mask_' + [pitch, octave, x1, x2].join('_')

  let y1 = pitch_y(pitch, octave)

  let w = (x2 - x1) *0.4,
    hw = w/ 2

  let scale_y = w > 3 ? 14/w * 0.2 : 1

  return h('svg.tie', {
    style: {
      transform: `translate(calc(${2+0.05 +x1*0.25 - w*0.16}em), calc(${y1-w*0.12-(scale_y*3-2)*0.15}
em)) scaleY(${scale_y})`
    },
    attrs: { width: `${w}em`, height: `${w}em`, viewBox: '0 0 100 100' }
  }, [
    h('defs', [
      h('mask', { attrs: {
        id: make_mask_id
      }}, [h('circle', {
        attrs: { cx: `${50}`, cy: `${50}`, r: `${200}`, fill: 'white' }
      }),/*
      h('rect', {
        attrs: { x: 0, y: 0, width: `${hw}em`, height: `${hw}em`, fill: 'black' }
      }),
    */
      h('circle', {
        attrs: { cx: `50`, cy: `${66-0.1*Math.sqrt(2*w)}`, r: `${60+0.4*Math.sqrt(10*w)}`, fill: 'bla
ck' }
      }),
      h('circle', {
        attrs: { cx: `10`, cy: `50`, r: `40`, fill: 'black' }
      }),
      h('circle', {
        attrs: { cx: `90`, cy: `50`, r: `40`, fill: 'black' }
      }),
      ])
    ]),    h('circle', {
      attrs: { cx: `50`, cy: `50`, r: `50`, fill: 'black', mask:`url(#${make_mask_id})` }
    })
  ] )
}

It looks like this:

<svg class="tie" width="1em" height="1em" viewBox="0 0 100 100" style="transform: translate(calc(1.9em), calc(0.48em));"><defs><mask id="m1"><circle cx="50" cy="50" r="200" fill="white"></circle><circle cx="50" cy="64" r="61" fill="black"></circle><circle cx="10" cy="50" r="40" fill="black"></circle><circle cx="90" cy="50" r="40" fill="black"></circle></mask></defs><circle cx="50" cy="50" r="50" fill="black" mask="url(#m1)"></circle></svg>


<svg class="tie" width="7em" height="7em" viewBox="0 0 100 100" style="transform: translate(calc(1em), calc(1em));"><defs><mask id="m1"><circle cx="50" cy="50" r="200" fill="white"></circle><circle cx="50" cy="52" r="67" fill="black"></circle><circle cx="10" cy="50" r="40" fill="black"></circle><circle cx="90" cy="50" r="40" fill="black"></circle></mask></defs><circle cx="50" cy="50" r="50" fill="black" mask="url(#m1)"></circle></svg>

Only problem is I can't control the thickness of this line. As the width gets bigger thickness gets too thick.

Please someone modify this solution to factor in line thickness for bigger widths.

Edit

I noticed I was using the same id, in the previous version, so I made sure each element gets a unique mask id, so that helped with the tweaking. I was wondering why my changes on the mask doesn't reflect on the render.