Pioneer SP-BS22-LR Dennis Murphy upgrade

Description

This published crossover design is an upgrade to the original design and is to be accompanied by replacement of the stock tweeter with the Vifa BC25TG15-04.

This speaker has been out of production for several years, but remains well regarded. In response to a customer request in Oct. 2025, I was happy to see the tweeter still available at Digikey for $15 each.  Link to tweeter.

This is intended as a budget winner, so the component options offered reflect that. Additionally, the cabinet space and woofer opening size are somewhat limited, so respect for those size limitations should also be factored.

Recommendations:

Capacitors: This design benefits from low capacitance values, which allows for very affordable components. The “upgrade” options are relatively affordable and are worth your consideration.

Bypass Capacitors: Bypass caps are offered as an add-on and the two pairs would be intended for placement on the in-line 2.2uf and 3.9uF tweeter capacitors. Bypass capacitors can provide an affordable performance gain. The JB JSX 0.22 bypass offered for this kit are a fast, clean, and resolving capacitor, representing a great value at $1.49 each x 2 pairs.

Inductors: 18-gauge is provided as standard, which aligns with the budget mindedness of this design while providing gains over a standard 20-gauge. If you have a preference for 20-gauge or 16-ga please reach out by email and we can modify for you.

Resistors: We have kept it very simple here. High-Quality resistors are very affordable. There are only two resistor in the circuit. We are providing GR Research branded 10 watt resistors ($4.00 each), for each resistor value.

Wiring: The cabinet is fairly small. 10ft of each color is plenty for this design. We are also offering an option for 20ft of each color if you want to purchase discounted wire for an additional or future project.  Wire is priced at 20% discount.  You may also purchase the kit without our wire.

We do think our wiring is the best value available. It is a premium wire without the traditional markups. We offer 16ga solid strand, high-purity OFC, Polyethylene insulator, made in the USA.  Wire details are here.