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Boston Acoustics SA1

Subwoofer amplifier

13 Reviews | 3 questions - 8 answers

Item # 065SA1

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Our take on the Boston Acoustics SA1

The SA1 amplifier provides high-quality power for up to two compatible Boston Acoustics subwoofers. Selectable crossover and equalizer settings let you achieve an optimal blend of sound with your other speakers. The auto on/off feature allows for more streamlined operation — you won't have to take any extra steps to power on this amp before listening to music or watching a movie. Plus, the SA1 can be stacked with the rest of your audio components or rack-mounted in a closet or cabinet for out-of-sight installation.

Product Highlights:

  • 140 watts (mono) RMS into 8 ohms, or 210 watts RMS into 4 ohms
  • gold-plated stereo line-level input
  • unfiltered LFE (Low Frequency Effects) input for connection to a home theater receiver's subwoofer output
  • two sets of binding posts for speaker-level output
  • continuously variable 40-160 Hz, 24 dB/octave low-pass crossover
  • selectable auto-sensing power on/off
  • selectable equalizer settings
  • phase control
  • selectable 12-volt trigger for use with 3rd-party control systems
  • rack-mountable design
  • detachable AC power cord
  • 3-1/2"H x 19"W x 12-1/2"D
  • warranty: 1 year
  • Our 60-day money-back guarantee

Well built and was able to drive twin subs. auto shut off works great.

Anonymous, Pennsylvania

What's in the Box:

  • SA1 Subwoofer amplifier
  • 5.75' AC power cord
  • Product manual
  • Warranty sheet

Boston Acoustics SA1 Reviews

Average Customer Review(s):

(13 Reviews)

Excellent subwoofer amp

Todd from Roanoke, VA on 10/24/2016

Crutchfield Customer Review (What's this?)

Purchased this to power 2 12in 4 ohm subwoofers in custom built sealed enclosures. Had been using a 25 yr old sony amp that finally quit working. I'm glad it did. I've been needing an excuse to spend the money on a real subwoofer amp. The auto on-off music sensing feature is great, no more having to manually turn on and off the amplifier. The SA1 has plenty of power for my 2 12 in subs. I'm using the LFE on my receiver in average size family room and sounds great with music and movies with volume on amp set at only a quarter of the way. For $399 plus tax you can't go wrong.

Pros: great sound and power

Cons: May not fit in entertainment cabinet because of rack mount option. Other than that no problem

Outstanding Sub Amp

Gerald from Mays Landing, NJ on 6/3/2016

Crutchfield Customer Review (What's this?)

Purchased this little beast after the plate amps gave up in my JBL PB10 powered subwoofer. After doing some research I desided to go with this unit and I'm glad I did! It did such a good job I decided to hunt for another JBL PB10 with a bad amp to also hook it up to this bad boy! This amp and the 2 subwoofers have proved to work great together, better than having the old plate amps repaired! I'm watching Star Wars (all of them) again and loving it!

Pros: Easy to hook up Good power Good price Clean sound 2 subwoofers can be connected

Cons: None

Boston Acoustics SA1

B..Man from Danbury, CT on 3/21/2016

Crutchfield Customer Review (What's this?)

This dedicated subwoofer amplifier is a very solidly built unit. It is powering a 12"dvc 4 ohm x2 car sub made into a custom home subwoofer enclosure. It has excellent response and power. This unit also allows the ability to use the dedicated LFE input from your home receiver to control crossover levels. If more user control is needed, there are are also standard RCA preamp left and right channel inputs that allow users to tweak the low pass crossover located on the front panel. All in all, this is an excellent unit.

Pros: Built like a tank. Clean power output.

Cons: Cost

Boston Acoustics SA1

Anonymous from Pennsylvania on 11/8/2015

Crutchfield Customer Review (What's this?)

Well built and was able to drive twin subs. auto shut off works great.



Boston Acoustics SA1 Review

Howard L from California on 11/6/2015

Crutchfield Customer Review (What's this?)

i love the fact that the unit is rack mountable as i plan to install it in a vintage Pioneer entertainment 'rack'. it has dual output so it is perfect for me as i will be running two separate subwoofers. having the unit rack mounted allows me to audition (and experiment) with different subwoofers easily. the unit exudes old school charm and workmanship and it's just delightful to have and use. quality never goes out of style and i am really glad Crutchfield have these units In Stock.

Pros: Rack mountable Superb workmanship/layout weight distribution and balance of the unit feels 'right'


Love to rattle the house

Big-D from Florida on 10/7/2015

Crutchfield Customer Review (What's this?)

I've been running a 12 inch JBL with the manufactures in box amp, which burnt up 3 times. Found an old amp from the 70's which worked "ok" for about a year and then died. Found this amp here on Crutchfield, thought the price, a little high for my budget, boy was I wrong. Man this thing sounds better than any amp I've used to date. Now I can rattle the house. movies, and regular TV shows sound great. The directions say start out on around 4 or 5 on the volume and go up or down from there, I have it around 4 + for Blue-rays and 1-3 for TV viewing, and some times that's too much. This unit is worth every dollar. Thank you Boston Acoustics and Crutchfield.

Pros: Belts out more sub bass than you expect. fully adjustable. Bass sounds from you favorite TV shows, you never heard before.

Cons: None.

Powering M&K push/pull

Rick from Pennsylvania on 8/31/2015

Crutchfield Customer Review (What's this?)

My SA1 is powering an M&K MX125II. It M&K is a wonderful subwoofer, designed by Ken Kriesel. The original amp blew and could not figure out the issue. Finding a dedicated sub-amp, not designed for autos is very difficult. I purchased a plate amp from a different online retailer which proved to be a failure. Though rated at over 150watts, it could not drive the push/pull design and ended up failing within a week. The retailer issued a refund and call-tag without issue. I found the SA1 and it has been running wonderfully for the past 6 weeks. It lacks the immediacy of the original amp, but maintains the very musical sound of the subwoofer. The 2 outputs are driving a pair of 4ohm 12" drivers in a push/pull design. It is done by wiring the speakers out-of-phase. As one drivers is pushing outward, the other is moving in the opposite direction. I purchased an "open-box." It was very well packaged and there seems to be no issue thus far. The bypass filter seems to be accurate and the control knob offers nice resistance.

Pros: Looks good. Line-level inputs. Dual speaker outputs. Output modified for either wall or floor mounting. Auto shut-off. Bypass.



justin from Portsmouth, va on 4/7/2015

Crutchfield Customer Review (What's this?)

Great product. Powerful, and simple to use

Pros: Ease of use, low pass filter

Cons: None found

Boston Acoustics SA1

Don from Texas on 4/6/2015

Crutchfield Customer Review (What's this?)

I replaced my old SA-2 amp with the Boston Acoustics SA1. Set-up was easy. I'm driving two passive 10 inch woofers and it works great. The build quality is solid. The sound it produces is superior to the old SA-2. It delivers great punch while maintaining pure crisp bass. The bass runs in my music never sounded better. I highly recommend the Boston Acoustics SA1

Pros: Produces powerful clear bass without any muddy affects.

Cons: None

At last...

Devilsmane from Chesapeake, VA on 9/30/2014

Crutchfield Customer Review (What's this?)

About 5 years ago after Boston Acoustics stopped making their outdoor bass speaker I bought it to use in a home I thought I was buying. Unfortunately the economy decided otherwise and I never purchased the SA1 amplifier. On a couple of different occasions I searched for the item but it could not be found and was also out of production. A couple of weeks ago I hauled the unopened woofer from storage and decided to try and sell it of give it away but decided to make one last attempt to find the amp on line. I was suprised to see that Crutchfield had these in unopened boxes in stock and new.

Pros: I decided to integrate the SA1 with the woofer in my home theater system. 1. Easy hookup using a trigger and a second bass output from my existing receiver and a Reference Furman. 2. No hum and powerful bass. 3. Integrated into an all Martin-Logan speaker system beautifully as a side woofer.

Cons: None


Bob from Minnesota on 8/13/2014

Crutchfield Customer Review (What's this?)

Although any older design, the SA1 was extremely easy to hook-up and had all the features I was looking for. I am driving two 15 inch sub woofers and the 2 speaker outputs work very well.

Pros: Easy hook-up and small size.

Cons: None noted yet.

SA1 subwoofer amplifier

Anonymous from Southeastern, Pennsylvania on 4/19/2013

Crutchfield Customer Review (What's this?)

This subwoofer amplifier and its twin from Snell are very good, reliable products. This is my second and powers an in-wall Snell subwoofer used with a Snell IW-K7 in-wall array. The Snell satellites are driven by a Pioneer SC63 receiver. The room is approximately 2200 cubic feet. The original SA-1 is perhaps ten or more years old and is used with second generation Technics THX subwoofers which present a four ohm load. The Technics is used as part of a second generation Technics THX array. The satellite speakers are driven by a Linn 5125 amplifier. The room has Acoustic Sciences sound treatment and is approximately 1500 cubic feet. I did not know there were any SA-1's left and had tried a Definitive Technology product without success. The Def Tech product sounded very boomy from the first moment. Nowhere in the Def Tech manual, which claims that the product can be used with other manufacturers' passive subwoofers, did it mention that the product has a non- linear low frequency boost of perhaps five or six dB.. A call to Def Tech confirmed what I heard, though the customer service person tried to suggest that it was not significant. I feel that Def Tech misrepresents their product. Unless there is a compelling reason to the contrary, I roll off subwoofers at 80 cycles as per THX recommendations. The nicely made Boston has an equalization switch for wall and floor. While not "high end," the Boston is more than ample for the applications.

Pros: It just plain works without difficulty

Cons: In my opnion, it would be nice to have both adjustable low pass and high pass filters for some of the more challenging passive subwoofers

boston amp

toodles from West Fargo,ND on 12/26/2010

I have this amp running boston pri85 subs(two in ceiling).and it pounds them.As a technical note i contacted boston prior to buying this to make shure it would run two subs.It does what people dont know is this amp has two sub channels,both are seperate 4 ohm capable channels,running at max 210 watts rms on each channel for a total of 420 watts rms for two speakers.this is a nice feature and makes wiring two subwoofers extremely versitile.either 8 ohms or 4 ohms on each channel,but the boston rep did say they suggest you run the same ohms on both channels.either way this is a clean powerhouse for subwoofers,that has the option to be rack mounted or wall mounted; also a nice touch.can't reccomend BOSTON ACOUSTICS,denon,murantz enough.they are one of the few companies that have fantastic customer service.




Hands-on research

Product Research



Overview: The SA1 amplifier is designed to be used with the Boston Acoustics line of installed subwoofers. One SA1 amplifier can power up to two of the same model subwoofer.

Variable Crossover: The amplifier has a built-in variable crossover that makes it easy to achieve a seamless blend with the main speakers, while the 24dB/octave low-pass filter prevents the subwoofer from being easily localized by the ear, increasing placement flexibility. The crossover point may be adjusted from 40-160 Hz.


Front Panel Controls:

  • Phase Switch: switches the polarity of the two speaker outputs; the correct setting is that which yields the fullest bass
  • Low-pass Knob: allows you to adjust the low-pass crossover point from 40-160 Hz
  • Volume Knob: allows you to adjust the volume level up or down until the bass level of your subwoofer matches the bass level of your speakers

Rear Panel Controls:

  • EQ Mode Switch: allows you to select one of the following EQ modes, depending where your subwoofer is located: Wall or Floor
  • 12-volt Trigger Switch: allows you to choose one of the following settings:
    • On: amp is on whenever the front panel switch is in the On position
    • 12V: amp is in standby mode whenever the front panel switch is in the On position. The SA1 turns on when a 12-volt power supply triggers it.
      • Note: Be sure to use a power supply that is rated as, "9 to 14 volts DC @ 1.5mA max. 1/8" diameter female plug with tip positive."
    • Music: amp is in standby mode whenever the front panel switch is in the On position. The SA1 turns on when an audio input signal triggers it.


Rear Panel Connections:

  • Line In: left and right RCA audio jacks; use this configuration if you wish to set the subwoofer crossover point using the SA1's low-pass control knob on the front panel or are using separate components, such as stereo preamplifier.
  • LFE/Xover Bypass: single RCA audio jack; in this configuration, the SA1's internal low-pass filter and front panel low-pass control knob will be bypassed
  • Speaker A/Speaker B: gold-plated binding posts; the binding posts are not 5-way because a plastic collar prevents their use with spade lugs

Our Product Research Team

At Crutchfield, you'll get detailed, accurate information that's hard to find elsewhere. That's because we have our own in-house Product Research team. They verify what’s in the box, check the owner's manual, and record dimensions, features and specs. We stay on top of new products and technologies to help people make informed choices.

Q & A

Customer Q&A

Crutchfield asked  
Why did you buy this?

Based on your favorable user review, I will power my M&K subwoofers which have failed amps. [ J EDWARD  Mar 21, 2017 ]
They are great to power powered subwoofers whose amps have gone bad. [ Gerald  Aug 01, 2016 ]

3 questions already asked

To be honest I'm not sure. Here's what the manual says below. Hope this helps. SPA200 Specifications Amplifier Power (< 1% THD) 140 watts continuous, 8 ohms; 210 watts continuous, 4 ohms Crossover Frequency 40-160Hz 24dB/octave lowpass Inputs L and R stereo RCA line level and LFE RCA line level for crossover bypass 12-volt trigger input voltage 9 to 14 volts DC @ 1.5mA max. 1/8" diameter female plug with tip positive External Dimensions (H x W x D) 31/2 x 19 x 121/2" (89 x 483 x 318mm) without feet 35/8 x 19 x 121/2" (92 x 483 x 318mm) with feet 2 EIA Rack space with feet removed Weight 18 lbs (8kg) Finish Black Description Snell's new SPA200 subwoofer amplifier and accompanying subwoofer speaker system deliver the dynamic bass foundation that is essential for lifelike reproduction of movie soundtracks and music in the home. The amplifier has a built-in variable crossover that makes it easy to achieve a seamless blend with the main speakers, while 24dB/octave lowpass filters prevent the subwoofer from being easily localized by the ear, increasing placement flexibility. A crossover bypass position is provided for use with home theater electronics that perform their own bass management functions. The SPA200 is attractively housed in a standard compact 2 space x 19-inch rack enclosure. Auto on off and 12volt amplifier switching and easily accessible controls make the SPA200 subwoofer amplifier as convenient to use as it is exciting to listen to. [ Donald  Feb 06, 2017 ]
Hope this answers question. The SA1 is a subwoofer amplifier with a crossover frequency of 40-160 24db/octave low pass. It's a variable crossover for subs and not for mids/highs/lows on speakers. An active crossover would separate mids/highs/lows so no its not. [ Clyde  Feb 01, 2017 ]
Gerald Irons Jr's and Nick Mazzarella's answers are correct on how to connect a subwoofer amp like this one to a theater receiver. HTH!! My Bio: [ Paul  Sep 10, 2016 ]  Staff
Your amplifier has a coax amp output, that will connect to the lfe input on the sub amp. The sub amp then connects to the speakers through audio out speaker line. [ Nick  Sep 06, 2016 ]
The Boston Acoustic SA1 Subwoofer Amplifier is exactly that. An amplifier that will power up to 2 seperate subwoofers that are passive. You connect your subwoofer preamp output from your receiver or integrated amplifier to the line input of the SA1. Then you run your speaker wires as you would any other type of speakers positive to positive and negative to negative and you are set. This amplifier is meant for passive subwoofers. It may as in my case also be used in powered subwoofers that have bad factory amps by simply bypassing the subwoofers factory amplifier and connecting the positive and negative cables from the SA1 to the positive and negative posts on your subwoofers. I use it this way first disconecting the subwoofers from the bad factory amps and connected them to the subwoofers passing the cables thru the exhaust ports. It's better and cheaper that having the factory plate amp repaired or replaced if the warranty is expired! [ Gerald  Sep 06, 2016 ]
If you purchased the product from Crutchfield, feel free to contact our Tech Support team. They can walk you through the settings on the product and see if there may be a fix. Our toll-free Tech Support number is printed on your invoice, and is also available under the "My Orders" tab in the "My Account" section of our website. If you did not purchase the unit from Crutchfield, then you may want to contact the manufacturer. You can also post your question in our forums: Or try our online support center: [ Krissy  Sep 06, 2016 ]  Staff
Dear John: Thank you for your question about the Boston Acoustics SA1 which Crutchfield forwarded to me. I am not sure that I fully understand your question, but I may give you some usable information to reach a conclusion. I have two SA1's in two home theaters. One has been driving a Snell subwoofer in a Snell in wall array which is nominally rated at 6 to 8 ohms for almost two years. The other is driving a second generation pair of Technics THX subwoofers in accordance with the original Technics directions which have these two subwoofers wired in parallel. The Technics subwoofers wired in parallel are connected to a single output on the SA1 and have a total nominal impedance of four ohms when wired in parallel across the SA!'s output terminal. The SA1 driving the Technics has been in place for perhaps ten years. Before I bought the SA1, I had discussion with Boston or Snell (Snell had been purchased by Boston) and was assured that the SA1 could easily handle a four ohm load, which it has here for about a decade. If you are asking if the SA1 can easily drive a two ohm load, I really do not know and would be reluctant to do that with any home subwoofer amplifier without speaking with the manufacturer or better yet, getting something in writing regardless of the stated specification. It has been years since I spoke to anybody in Boston and Snell is now defunct, but their customer service was very, very good and the people I spoke to knew their products very well. I believe that Boston is still selling a passive subwoofer (in-ceiling?) which uses the SA1, so there must be somebody left who has thorough knowledge of the SA1. If possible, please have the Crutchfield people let me know what you end up doing. While the SA1's build quality is no match for the ultra high end, it s a very good product and has been extremely reliable. If there are quirks, even after a decade of use, I have not found them. Jerry [ JEROME  Aug 23, 2014 ]
I believe the answer is yes. I have 5 of these units installed, however I am only driving single coil subs in each application. The unit drives both outputs identically, so I would think from the SA-1's perspective it would think it is simply driving two 4 ohm subs. The amp is great, and applies a curve to bass output to properly accentuate lower volume levels. [ michael  Aug 22, 2014 ]