Aria Pro II SB-1000 BB active preamp, retrofit/restoration 1977-1986

**** Briefly out of stock - new parts in 1-2 weeks! Email for info ****

Updated listing: https://reverb.com/en-fi/item/73657979-ariaproii-sb-1000-bb-noisekiller-preamp-replacement-upgrade-1977-1987

This listing is for replacement pre-amps for vintage 70s-80s Matsumoku Aria Pro II SB-1000 basses. These pre-amps are straight swaps for the original preamp circuit with identical function, but includes improvements through modern precision components and PCB manufacturing for the strongest and cleanest tonal quality. All preamps are manufactured in Finland and individually hand-tested.

NOTE: Two versions of the preamp are available. We recommend the OPA-based preamp as it is far superior to the original design in every aspect! This listing is priced for the OPA version. If you absolutely definitely cannot live without a JRC-based preamp, simply put in an offer for 10% off the listing price and send us a message. :-)

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The pre-amp was also found in the very limited SB-R150 and SB-800 basses in addition to the less well known NK-700/800 series of guitars. Beyond Aria Pro II instruments, this preamp can be used in custom hybrid electric circuits to eliminate hum and noise in most instruments provided they can be fitted with a switched jack and two 9v batteries or other balanced supply.

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The components in the original Aria Pro II pre-amps are now 40 years old, far older than the decade or so they were expected to work for! Those that haven't failed have inevitable component aging and performance degradation. Original pre-amp circuits were never made available as aftermarket replacements meaning many vintage SB-1000s end up gutted of their active electronics, fitted with a different pre-amp (such as the modern Aria Pro II SB-1000 re-issues which are different ) or left to run as a simpler passive bass. Without the original circuit much of the versatility and distinctive SB-1000 sound owners hunt for ends up lost.

This version of the 10-pin BB Noisekiller pre-amp design is compatible with both the original 1978-80 "batwing" SB-1000 basses, the later 80s models with the blinking LED and other bass and guitar models featuring this preamp. Like the originals they are a plug-and-play design that only require that the connector be pulled from the old unit and pushed onto the new one. See note below about connector orientation.

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In the decades since the original SB-1000s were made, electronic components have improved in technology and quality by magnitudes. Our preamps are true to the original design's functionality and tone, but exceed the originals in both performance and audio quality; the intrinsic muscular sound of the pre-amp is the same, but with the bonus of increased reliability, fidelity and current consumption. We opted to use the stellar Burr Brown OPA2227 for our modern version of the BB preamp, along with laser-trimmed metal film resistors, high-spec Japanese capacitors, turned pin IC sockets, heavy copper PCBs and larger grounding planes for noise rejection. For those that insist on absolute vintage reproduction purposes we also offer pre-amps designed around the original JRC4558 chips and component types as per the originals.

In general we recommend the modern variants over the original design every time, purely because of the performance and battery life advantages rather than any tonal difference. JRC4558 chips are 70s tech with no mojo in this configuration!

As per the originals, pre-amps are epoxy potted in an ABS case to protect the circuit. Pre-amps are fitted with an unkeyed 10-pin header. It is imperative to ensure that the pre-amp is oriented in the same direction as the previous unit when plugging in the connector, ie. PCB the same side of the connector. The listing photographs show a new unit and an original in the same alignment. All pinout labels are silkscreened onto the PCB, however confirmation of orientation can easily be made via email if you are unsure.

Product FAQs

Q. Can I upgrade a passive bass to active using these preamps?

A. Yes. The only caveats being that you will need to swap out your volume and tone pots to lower values (20-25k) and fit a switched DPDT jack socket to manage the 2x 9v battery supply. A Molex KK or TE CST-100 connector is all you need to fit the pre-amp. These are available from electronics suppliers or here on eBay also. You will of course also need space for the batteries and pre-amp which are generally not as easy to acquire! Gotoh dual battery boxes are a nice option, and generally the preamp itself seats on the rear of a cavity plate. I've fitted several instruments with SB-1000 type circuits from custom 5-string basses to Telecasters.

Q. Can the pre-amp be run on a 9v supply?

A. Yes and no but mostly "no". The pre-amp works on a balanced supply hence the two batteries. Whilst it is possible to fudge a solution to use only one battery, the impact on the noise cancelling capability and overall signal headroom make the negatives outweigh the positives. It's easier to work with "no" than the headaches associated with a poor "yes"!

Q. I bought my bass with the pre-amp missing. Which way around do I fit this pre-amp?

A. The three pins marked "PWR" on the pre-amp PCB correspond to the three wires that supply voltage. These are most commonly red/orange/blue from the outside in. The red and blue wires should lead to two of the jack socket tags whilst the orange leads to the batteries.

Q. My bass has been completely gutted! Can I buy new pickups, electronics, etc?

A. Ouch. Importantly, repro pickups can be bought through Kent Armstrong. The electronics are a bit more difficult. The stacked pots in the 1981-1986 SB-1000 are impossible to buy outside of a custom order of a few thousand (!!). The varitone and rest of the electronics loom can be reproduced also. The downside is that the complex nature of the electronics and the amount of time involved in fabrication means they're not a cheap option. 1977-1979 SB-1000s (active only) were much simpler and can be reproduced using standard components. As you'd expect, retrofitting is easier done with the bass on the bench so we don't offer drop-in looms any more. By all means drop us an email for advice and we'll always help one to one as best we can.

Q. The battery LED circuit on my 80s SB-1000 is causing clicks in the audio. Is this normal?

A. No, or at least it is not what is supposed to happen of course. Component aging causes components such as the capacitors to leak current or other unwanted things. The upshot of this is that the LED blinker circuit (the one wrapped in electrical tape) injects noise spikes onto the pre-amp supply, which is then pushed onto the audio signal as clicks or "pulses" if the preamp's supply smoothing components are also leaky. We may provide a replacement LED blinker in the future. Email for more info.

Customer Comments

- "[the pre-amp] opened up [the bottom end] drastically and is a lot less muddy than with the original BB preamp. The high mids and highs are a lot cleaner as well"
- "I thought something was wrong because it was almost silent compared to how it used to be. I almost **** myself because I turned [the amp] right up before I played it!"
- "I haven't used the [rotary] switch for years after the old one crapped out on me and I forgot how deep the bass sounds"
- "Sweet and transparent and the clicking from the LED stopped"