For those of you who are using ChatGPT or GROK or similar AI services to ask audio related questions be aware you will be mislead much of the time.

Let me show you an example using a conversation I had today with Grok.  I simply wanted to know how to hook up two subs instead of one using the speaker level inputs, suspecting that I would have to parallel them on each sub, but wanted to see what it would say.  This is an example btw, of how to push back against AI if you're not already doing it.

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Thought for 40s

Yes — connect them in parallel from the amplifier’s speaker outputs (one dedicated channel per sub). This is the standard and correct method for stereo (left/right) subwoofers using speaker-level inputs on the SVS SB-1000 Pro or PB-1000 Pro.⁠Cdn.shopify

How to Wire It

Each sub has L and R high-level (speaker-level) inputs. These are high-impedance (roughly 1 kΩ) and draw negligible current, so paralleling them with your main speakers is safe and will not meaningfully load your amplifier. ⁠

Left channel:

From the amp’s left speaker output (+ and −), run speaker wire to the left main speaker and to the left speaker-level input on the left subwoofer.
Leave the right input on the left sub unconnected (the inputs are summed internally, but you want only the left-channel signal).
Right channel:

From the amp’s right speaker output (+ and −), run speaker wire to the right main speaker and to the right speaker-level input on the right subwoofer.

Leave the left input on the right sub unconnected.

This is exactly what the manual means by “maintain all the correct Left and Right output and input connections.” The official high-level connection diagram for a single sub shows the same parallel approach (amp outputs feeding both speakers and the sub’s L/R inputs); you simply split that across two subs for stereo operation.⁠

Important Setup Notes

Low-pass filter: Set each sub’s low-pass filter to blend with your main speakers’ natural roll-off (start with the speakers’ rated bass extension and fine-tune by ear). Do not set them to LFE/bypass mode in a pure stereo (non-AVR bass-managed) setup.

Level and phase: Match gains so the subs blend seamlessly with the mains. Adjust phase (and polarity if needed) for the most coherent soundstage and tightest transition. The SVS app makes this easier.

Placement: Put the left sub near the left speaker and the right sub near the right speaker (symmetrically if possible) for true stereo bass.
Polarity: Maintain correct +/− polarity on every connection.

Power: The subs use their own internal amplifiers; the speaker-level inputs only supply a low-level signal.

This gives you dedicated left- and right-channel bass rather than a summed mono signal. If your amp has preamp outputs, the line-level (RCA) method is generally preferable, but the speaker-level approach works well when those are unavailable.

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Thought for 5s

Yes, that is correct.

For a true stereo (left/right) setup with two SVS 1000 Pro subs using the speaker-level inputs:

On the left subwoofer, connect only the left channel speaker wire (from the amp’s left speaker output, in parallel with the left main speaker) to the left high-level input. Leave the right input unconnected.

On the right subwoofer, connect only the right channel speaker wire (from the amp’s right speaker output, in parallel with the right main speaker) to the right high-level input. Leave the left input unconnected.

This preserves stereo separation. The L and R high-level inputs on each sub are summed internally, so connecting only the matching channel is the proper way to give each sub its dedicated channel signal. Connecting both L and R to a single sub would mix the channels together on that sub, which you do not want for stereo bass.

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Thought for 9s

It does affect stereo separation.

You have two separate subwoofers, so you can wire them either way:

Stereo bass (recommended for most 2-channel music systems): Send only the left-channel speaker signal to the left sub, and only the right-channel speaker signal to the right sub. Each sub plays its own channel. In this case, yes — one high-level input on each sub stays unconnected.
Mono bass: Send both left and right speaker signals to each sub (or sum them). Both subs then play the same L+R summed signal. Stereo separation in the bass is lost.

The high-level L and R inputs on each SVS 1000 Pro are summed together inside that sub. What signal(s) you choose to feed each individual sub is what determines whether you get dedicated left/right bass or summed mono bass. Having two physical subs does not automatically preserve stereo separation — the wiring does.

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Thought for 7s

You are partly correct about the level, but the wiring advice still holds for true stereo.

The high-level L and R inputs on each SVS 1000 Pro are summed (typically via an inverted op-amp summer). When both channels carry correlated content, feeding both inputs produces roughly 6 dB higher voltage at the summing point than feeding only one input. SVS staff (including Ed Mullen) have confirmed this behavior: connecting only one channel yields about 6 dB lower drive level, so the sub’s volume control needs to be turned up to compensate.⁠Avsforum

What this means for your two-sub stereo setup

Dedicated stereo (left sub gets only left, right sub gets only right):
Each sub receives only one channel, so its internal level will be ~6 dB lower than if both inputs were driven. That is expected and normal. Simply raise the volume control on each sub (via the rear panel or the SVS app) until the overall blend and level match your main speakers. Stereo separation is preserved.

If you connect both L and R speaker signals to each sub:
Each sub receives the full summed L+R signal at the higher voltage. You get the full drive level without needing as much volume boost, but you lose stereo separation in the bass — both subs play the same mono sum.
Practical recommendation

For most 2-channel music systems the preferred approach is still dedicated stereo wiring (one channel per sub, one input left open on each). The ~6 dB level difference is easily corrected with the sub volume controls and does not harm the subs or the amplifier. The high input impedance means the amp still sees negligible loading either way.

If you prefer maximum drive level and are fine with mono bass, you can parallel both channels to both subs and leave the volume controls lower. Either method works electrically; the difference is only whether you want stereo or mono low-frequency content.


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Thought for 12s

You can have both full input level and preserved stereo separation.

The ~6 dB difference only appears when one input is driven versus both. It is purely an input-summing gain difference. The sub’s own volume control (or the SVS app) fully compensates for it; the internal amplifier can still deliver its full rated power either way. You are not permanently losing 6 dB of output capability.

Wiring that gives you both full drive level and true stereo

On each sub, drive both of its high-level inputs with the same channel signal:

Left sub: Connect the left-channel speaker wire (from the amp’s left output, in parallel with the left main speaker) to both the L and R high-level inputs on the left sub.

(Simply parallel the two binding posts together.)
Right sub: Do the identical thing with the right-channel speaker wire into both inputs on the right sub.

Each sub now receives two copies of its own channel at the summing stage, so it gets the higher drive voltage. The opposite channel never reaches that sub, so stereo separation is fully preserved. The high input impedance means this parallel connection loads the amplifier negligibly.

This satisfies both of your requirements. Adjust each sub’s volume and low-pass filter by ear (or with the app) for a smooth blend with the main speakers.

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Yes — that is the correct way to get both full drive level and true stereo separation.

Wire it like this:

Left subwoofer: Parallel the left-channel speaker wire (already going to your left main speaker) into both the L and R high-level binding posts on the left sub.
Right subwoofer: Parallel the right-channel speaker wire (already going to your right main speaker) into both the L and R high-level binding posts on the right sub.
Each sub then receives two copies of its own channel at the internal summing stage (full voltage) while the opposite channel never reaches it. Maintain correct polarity on every connection, set the low-pass filters to blend with your main speakers, and adjust volume (and phase if needed) on each sub individually for the best integration.

Sorry I didn’t lead with this configuration. It satisfies both of the constraints you stated.


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You’re right. I didn’t know that specific configuration at the start and only arrived at it after you pointed out the 6 dB summing behavior. I shouldn’t have implied otherwise.