Refer to my post Brioche Tutorial 1 for terminology and other general information.
1. Double Brioche Stitch
Double brioche stitch refers to a brioche fabric where each of the ribs in the fabric are two stitches wide instead of one stitch wide. This creates a wider, flatter ribbed effect which looks like this (two-colour version):

The basic terminology I use for double brioche is:
sl2yo:
With yarn in front, slip the next 2 stitches to working needle and bring yarn back over the needle so that it wraps over the two slipped stitches.


brk2:
Knit the first stitch with its yarnover, as for a brk stitch, but do not slip the yarnover off the passive needle, then knit the second stitch together with the yarnover and slip both the stitch and its yarnover off the passive needle.


2




brp2:
Purl the first stitch with its yarnover, as for a brp stitch, but do not slip the yarnover off the passive needle, then purl the second stitch with the yarnover and slip both the stitch and the yarnover off the passive needle.





Chart Symbols
This key shows the chart symbols I use throughout this tutorial:

One-colour Double Brioche Stitch Worked Flat

This is worked over a multiple of 4 stitches:
- Set up row: *sl2yo, k2; rep from * to end.
- Row 1 (WS): *sl2yo, brk2; rep from * to end.
- Row 1 (RS): *sl2yo, brk2; rep from * to end.
- Continue repeating both iterations of round 1.
Two-colour Double Brioche Stitch Worked Flat
Refer to my post “Brioche Tutorial 1” for an explanation of the row numbering system. In this example the stitch commences with a set-up row on the dark side of the fabric.

- Using LC yarn, cast on loosely a multiple of 4 stitches. Slide stitches to other end of needle and join in DC yarn.
- Set-up row DS DC: using DC yarn, *p2, sl2yo; rep from * to end. Turn work.
- Row 1 LS LC: using LC yarn, *brk2, sl2yo; rep from * to end. Slide stitches back to other end of needle.
- Row 1 LS DC: using DC yarn, *sl2yo, brp2; rep from * to end. Turn work.
- Row 2 DS LC: using LC yarn,*sl2yo, brp2; rep from * to end. Slide stitches back to other end of needle.
- Row 2 DS DC: using DC yarn, *brk2, sl2yo; rep from * to end. Turn work.
- Continue repeating rows 1 & 2.
In this example additional selvedge stitches have been ignored, however see my Brioche Tutorial 1 for some suggested selvedge ideas. The use of a selvedge can make it easier to work the sl2yo at the edges of the piece. The stitch can also be worked over a multiple of 4 stitches + 2 for a symmetrical pattern.
Two-colour Double Brioche Stitch Worked in the Round
In this particular example two set-up rounds are worked, one in each yarn colour.

- Using LC yarn, loosely cast on a multiple of 4 stitches. Join to work in round taking care not to twist stitches. Place marker.
- Set-up round LC: using LC yarn, *k2, sl2yo; rep from * to end of rnd. Leave LC yarn at back of work and join in DC yarn.
- Set-up round DC: using DC yarn, *sl2yo, brp2; rep from * to end of rnd. Leave DC yarn at front of work.
- Round 1 LC: using LC yarn, *brk2, sl2yo; rep from * to end of rnd. Leave LC yarn at back of work.
- Round 1 DC: using DC yarn, *sl2yo, brp2; rep from * to end of rnd. Leave DC yarn at front of work. Ensure that the final brp picks up the LC yarn which is wrapped over the final two stitches.
- Continue repeating round 1 using LC and then DC.
Note: at the end of each round, avoid twisting or crossing the yarns over each other.
2. Syncopated Brioche Stitch
Syncopated brioche refers to a stitch pattern where the columns of brk stitches on the front side of the fabric switch to being columns of brk stitches on the back side of the fabric; at the same time the brk columns on the back side of the fabric become brk columns on the front. Here is an example worked in two colours:

In two-colour syncopated brioche the pairs of rows or rounds continue to be worked first using LC and then DC; the change in pattern is due to the stitch columns previously worked as brk stitches being worked as brp stitches, and vice versa.
Two-colour Syncopated Brioche Worked Flat

- Using LC, loosely cast on an even number of stitches. Slide stitches to other end of needle and join in DC yarn.
- Set-up row LS DC: using DC yarn, *sl1yo, p1; rep from * to end of row
- Row 1 DS LC: using LC yarn, *sl1yo, brp1; rep from * to end of row. Slide stitches to other end of needle.
- Row 1 DS DC: using DC yarn, *brk1, sl1yo; rep from * to end of row.
- Row 2 LS LC: using LC yarn, *brk1, sl1yo; rep from * to end of row. Slide stitches to other end of needle.
- Row 2 LS DC: using DC yarn, *sl1yo, brp1; rep from * to end of row.
- Continue repeating rows 1 & 2 the required number of times.
- Row 3 DS LC: using LC yarn, *sl1yo, brk1; rep from * to end of row. Slide stitches to other end of needle.
- Row 3 DS DC: using DC yarn, *brp1, sl1yo; rep from * to end of row.
- Row 4 LS LC: using LC yarn, *brp1, sl1yo; rep from * to end of row. Slide stitches to other end of needle.
- Row 4 LS DC: using DC yarn, *sl1yo, brk1; rep from * to end of row.
- Continue repeating rows 3 & 4 the required number of times.
- Continue alternating between several repeats of rows 1 & 2, then several repeats of rows 3 & 4.
Two-colour Syncopated Brioche in the Round

- Using LC, loosely cast on an even number of stitches. Join to work in round taking care not to twist stitches. Place marker and join in DC.
- Set-up round DC: using DC yarn, *sl1yo, p1; rep from * to end of rnd. Leave DC yarn at front of work.
- Round 1 LC: using LC yarn, *brk1, sl1yo; rep from * to end of rnd. Leave LC yarn at back of work.
- Round 1 DC: using DC yarn, *sl1yo, brp1; rep from * to end of rnd. Ensure that the final brp picks up the LC yarn which is wrapped over the final stitch. Leave DC yarn at front of work.
- Continue repeating round 1 LC and round 1 DC, the required number of times.
- Round 2 LC: using LC yarn, *brp1, sl1yo; rep from * to end of rnd. Leave LC yarn at back of work.
- Round 2 DC: using DC yarn, *sl1yo, brk1; rep from * to end of rnd. Ensure that the final brk picks up the LC yarn which is wrapped over the final stitch. Leave DC yarn at front of work.
- Continue repeating round 2 LC and round 2 DC, the required number of times.
- Continue alternating between several repeats of rounds 1 LC & DC, then several repeats of rounds 2 LC & DC.
3. Syncopated Double Brioche
This stitch pattern is worked as given above for double brioche but after every few pairs of rows/rounds the brp2 and brk2 stitches are swapped (in the same way as the brk and brp stitches are swapped as described for the single syncopated brioche stitch at section 2 above).

Two-colour Syncopated Double Brioche Worked Flat

In this example the set-up row is worked on the dark side of the fabric.
- Using LC yarn, cast on loosely a multiple of 4 stitches. Slide stitches to other end of needle and join in DC yarn.
- Set-up row DS DC: *k2, sl2yo; rep from * to end. Turn work.
- Row 1 LS LC: *brk2, sl2yo; rep from * to end. Slide stitches back to other end of needle.
- Row 1 LS DC: *sl2yo, brp2; rep from * to end. Turn work.
- Row 2 DS LC: *sl2yo, brp2; rep from * to end. Slide stitches back to other end of needle.
- Row 2 DS DC: *brk2, sl2yo; rep from * to end. Turn work.
- Continue repeating rows 1 & 2 the required number of times.
- Row 3 LS LC: *brp2, sl2yo; rep from * to end. Slide stitches back to other end of needle.
- Row 3 LS DC: *sl2yo, brk2; rep from * to end. Turn work.
- Row 4 DS LC: *sl2yo, brk2; rep from * to end. Slide stitches back to other end of needle.
- Row 4 DS DC: *brp2, sl2yo; rep from * to end. Turn work.
- Continue repeating rows 3 & 4 the required number of times.
Note: it is possible to work this stitch over a multiple of 4 stitches + 2 for a symmetrical pattern.
Two-colour Syncopated Double Brioche in the Round

- Using LC, loosely cast on a multiple of 4 stitches. Slide stitches back to other end of needle and join to work in round taking care not to twist stitches. Place marker and join in DC.
- Set-up round DC: using DC yarn, *sl2yo, p2; rep from * to end of rnd. Leave DC yarn at front of work.
- Round 1 LC: using LC yarn, *brk2, sl2yo; rep from * to end of rnd. Leave LC yarn at back of work.
- Round 1 DC: using DC yarn, *sl2yo, brp2; rep from * to end of rnd. Ensure that the final brp2 picks up the LC yarn which is wrapped over the final two stitches. Leave DC yarn at front of work.
- Continue repeating round 1 the required number of times.
- Round 2 LC: using LC yarn, *brp2, sl2yo; rep from * to end of rnd. Leave LC yarn at back of work.
- Round 2 DC: using DC yarn, *sl2yo, brk2; rep from * to end of rnd. Ensure that the final brk2 picks up the LC yarn which is wrapped over the final two stitches. Leave DC yarn at front of work.
- Continue repeating round 2 the required number of times.
- Continue alternating between several repeats of round 1, then several repeats of round 2.
It is interesting to note that the point at which the changeover happens looks different depending on whether the change occurs at the point between two consecutive brp rounds or two consecutive brk rounds. In other words, where round 1 DC is followed by round 2 LC, these are both brp rounds and it is possible to see the yarns being carried across the fabric. However, when moving from round 2 DC back to round 1 LC, these are both brk rounds which results in a more compact transition between the brk columns. In theory this also applies to single syncopated brioche but is less apparent where the columns of stitches are only one stitch wide.

