PinWoofer Amplifier External Subwoofer Options

Posted by PinWoofer on Jan 17th 2023

The output of the PinWoofer GT, GTP and KOP amplifiers have what's called "Pro" or "Studio" level which is of a higher voltage drive compared to consumer electronics. (The KO amplifier does not have an output.)

Therefore, if you want to run an external subwoofer in addition to the PinWoofer kit, you can use one of the below options. All of these options will provide a superior quality audio signal for your external subwoofer, compared to a speaker to line level option: 

1. BBU - Compatible with all PinWoofer Amplifiers – this is a powered unit and gives you an increase in signal level going to the powered sub. Also gives you the convenience of having your subwoofer controls at the coin door location. This option works with all PinWoofer Amplifiers:

PinWoofer Bass Boost Unit (

2. Line Trimmer - Compatible with PinWoofer GT, GTP and KOP Amplifiers – adds the convenience of having level adjustment at the coin door location. But it does not give you a signal boost like the BBU. However, the KOP amplifier output has lots of drive and this option is most popular and performs great for the KOP Amp. This option works with all PinWoofer Amplifiers (except for the original KO amp which has been discontinued), but is most suited for the KOP amplifier:

PinWoofer Line Trimmer (

3. CDU - Compatible with all PinWoofer Amplifiers but offered on Spike-2 only - this is the ultimate solution since it incorporates the electronics and functionality found in the BBU, but also adds a volume control, a headphone station and externalizes the service menu buttons. This item works as a stand-alone item (with or without a PinWoofer System), for all PinWoofer Amplifier Models:

PinWoofer Coin Door Unit (

4. Audio Cable - For Spike-2 only, and for use with the KO and KOP amplifiers – simple cable that runs from the line out board on Spike-2, then to the input of your external (one of two possible types of connection at the external sub). The below cables can also be used directly without a BBU or Line Trimmer for the older titles that use the GT / GTP amplifier. The quality of this source is good, but it has less dynamic range compared to the output of the PinWoofer amplifier. Still, this source is superior to using a speaker level to line level converter:

12ft 3.5mm Male TRS to RCA Stereo Audio Cable (

12ft 3.5mm Male TRS to Male TRS Stereo Audio Cable (