SVS SB-3000 - inside pics, personal thoughts
SB-3000 Subwoofer Owner's Manual, Quick Start Guide and manufacturer specs can help customers in how to properly setup and operate this subwoofer in their homes or studios.
I purchased a brand new 13” SB-3000 subwoofer, to replace the 12” SB-1000 pair I owned (reviewed here: https://www.audiosciencereview.com/...s-sb-1000-inside-pics-personal-thoughts.7842/) and used for the last couple of years. The reason for the upgrade was to reproduce a bit better the lowest octave (20...40 Hz), to gain a few more dBs SPL there, to adjust sub’s power and crossover remotely, but also to reuse living space a bit better (single sub vs. dual subs). In terms of pure power we’re comparing two SLEDGE STA-300D amplifiers with 300 W RMS each (720 W peak each) vs. one Sledge STA-800D2 amplifier having 800 W RMS (2500 W peak). The SPL difference is clearly audible from the very beginning, no questions asked. Actually, my gypsum-boards ceiling might suffer if I crank up the volume too high with SB-3000 connected. Good thing I recently swapped my windows with triple pane 44.2 / 4 / 33.1 Stadip Silence glass.
The lowest octave is better reproduced now and one SB-3000 sub is indeed an upgrade over my previous dual SB-1000 subs. The Apple Store SVS app is great, although sometimes I need to choose my desired sound profile twice to actually select it and actually make it work (only the first time after opening the app, probably some sort of "bug"). Having both crossover and EQ on the same app, but also being able to save more audio profiles for Music, Movies etc. brings a big smile on my face.
As you can see from the above pictograms, my room resonates at around 26 Hz and I needed to lower that frequency with about -9 dB, while at 22 Hz and 48 Hz I needed to increase the amplitude a little bit to flatten the output bass.
In-room measurement with REW app + ECM999 mic + Motu M4 interface - 2 x Canton GLE 496 + 1 x SB-3000 @90 degrees
I do like the output bass of the SB-3000 for both music and movies, although I'm aware that for movies a ported sub might have an advantage here. SB-3000 is connected to sub-out of the Yamaha A-S701 and I'm using from SVS's app a -18 dB volume for movies and a -20 dB volume for music to perfectly blend in the stereo speakers with the subwoofer. Choosing 2 dB more output for SB-3000 when watching movies is purely subjective and I chose this mostly for a better "boom" and "bang", especially on explosions, gunshots and...earthquakes.
Subwoofer’s case is made out of MDF with black polyvinyl on the outside. Sides, internal brackets and backside are having a thickness of about 18.5 mm (about 0.75 inches), while the front baffle is about double as thickness. Inner stuffing has a generous amount of 1 inch thickness properly glued.
Driver’s rubber outer diameter is 31 cm/12.2 inch, while entire driver’s size (the outer basket) is almost 35 cm/13.7 inch, so pretty close to 14 inch. The 7 inches wide double magnet is placed inside the internal bracket via soft black rubber tape to absorb inner vibrations.
Inside there is a big metallic plate, that also acts as a heatsink, containing the motherboard and input board that contains the DSP, input buffer and output buffer as well. Motherboard includes the isolated power supply and the amplifier parts.
The built-in DSP board contains a STM32 32-bit Arm Cortex M0 MCU with a core CPU running at 48 MHz (datasheet here: https://ro.mouser.com/datasheet/2/389/dm00090510-1797802.pdf), an ADAU1761 SigmaDSP 28-/56-bit, 50 MIPS digital audio processor and the Qualcomm® Bluetooth Low Energy platform technology 28-pin QFN chip CSR 1010 that works in concordance with the specification of BT 4.1 specs (https://en.wikipedia.org/wiki/Bluetooth#Bluetooth_4.1). This BT radio module (https://docs.qualcomm.com/bundle/publicresource/87-CE857-1.pdf) is not used for transmitting audio signals over the air, but for connecting your mobile device (phone, tablet) to the subwoofer DSP board, so you can properly adjust the built-in DSP and PEQ settings, based on the room measurements done with a dedicated measurement setup (REW etc.). We can also spot a DRV632 audio line driver that removes the DC from the audio lines, most likely used for RCA line-level outputs.
STM32 ARM Cortex M0 MCU
ADAU1761 DSP chip
There are two Class D chip amplifiers inside made by International Rectifier, IRS2092S (https://www.infineon.com/dgdl/irs2092.pdf?fileId=5546d462533600a401535675f1be2790), used with MOSFET output buffers in full bridge mode operation, for a higher output power. Same IRS2092S chip is also used (not bridged) in Mackie MR10Smk3 subwoofer too. More infos about this amplifier chip can also be found here: http://www.irf.com/product-info/fact_sheet/audio-irs2092.pdf. The output power MOSFET transistors are TO-220 case and could be IRFB4227PbF or something with similar specs. A dual-opamp JRC 4580 is most likely placed in the signal path, in front of the IRF chips.
Full bridge IRS2092S class-D amplifier
The built-in power supply has a decent EMI/RFI filter and lot of filtering capacitors. We can spot an off-line SMPS Current Mode Controller ICE3RBR4765JZ. It has a soft-start with two P33N60E (33A, 600V), a Power Factor Correction stage around UCC28063 a full bridge (https://www.bequiet.com/en/insidebequiet/15) with four P33N60E MOSFET transistors, an LLC design with L6599AD. You can check a great post from diyaudio forum (https://www.diyaudio.com/forums/class-d/371218-reapir-svs-pc-4000-1200-sledge-amplifier.html) where Reactance user was able to detail very well the PSU of a SB-4000, which is pretty similar with the one found inside SB-3000, and explain how to repair it in case it gets broken.
Common-mode mains filter and a big Metal Oxide Varistor (MOV) + fuse that offers basic protection in case of over-voltage (>255 VAC) for the electronic components of the SB-3000
Output buffer with MOSFET transistors (under the aluminum heatsink)
Power supply close-up
You can check manufacturer’s specifications here https://www.svsound.com/products/sb-3000#techanchor, but there are couple of great measurements and tests done by Audioholics (https://www.audioholics.com/subwoofer-reviews/svs-3000/conclusion) and Erin (https://www.audiosciencereview.com/...b-2000-pro-vs-sb-3000-subwoofer-review.21428/), so feel free to have a look, so you can make an opinion about the max. SPL, frequency response and THD vs. frequency for this rather small but great compression subwoofer.
Frequency response graph from SVS website
SVS offers a 5-years warranty on their subwoofers and is a company that has a very good reputation in dealing with RMA cases, per AVSFORUM, HomeTheaterForum and ASR forum as well.