This is a great sounding phaser so I thought I’d still do it even though it probably doesn’t fit with my philosophy of when I would and wouldn’t use vero. Similar in some ways to the Phase 90 but I haven’t seen a layout for this one and so decided it would be a good addition. Like the Phase 90 this is going to work best with 4 matched JFETs and so it may be worth buying 4 matched rather than buying in a greater quantity and having to mess around. The internal trimmer sets the bias point and so tweak that until you get the sound you want. The original also had the Depth control as an internal trimmer but I thought it made much more sense to have that control external to make it a bit more versatile.
If you mount this one sideways it should fit in a 125B but a 1590BB may be the order of the day if you don’t want to have to squeeze everything in. Thanks to Analogguru for the schematic.
Image from effectsdatabase:
And a revised layout making better use of the space so it could fit more easily in a 1590B, and based on 2N5457 JFETs for their availability.
Bill of Materials:
| Group | Value | Qty |
| Resistors | 6K8 | 2 |
| Resistors | 10K | 10 |
| Resistors | 22K | 4 |
| Resistors | 47K | 3 |
| Resistors | 100K | 1 |
| Resistors | 150K | 3 |
| Resistors | 470K | 2 |
| Resistors | 680K | 1 |
| Capacitors | 180p | 1 |
| Capacitors | 10n | 2 |
| Capacitors | 47n | 6 |
| Capacitors | 2u2 | 1 |
| Capacitors | 10u | 1 |
| Capacitors | 33u | 1 |
| Diodes | 1N5817 | 1 |
| Diodes | 4V7 Zener | 1 |
| IC | LM1458 | 3 |
| JFET | BF244A or 2N5457 | 4 |
| Trimmer | 1M multi-turn | 1 |
| Pot | 10KLog | 1 |
| Pot | 470K Rev Log | 1 |
| Pot | 1MLin | 1 |