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We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
If you want a neutral, studio-style tuning with a metal faceplate, a detachable cable and a mic for everyday device use, choose HIFIXAUDIO 7Hz; if you need a warmer, bass-forward listen with an around-ear fit that cuts cable noise and a full metal housing, choose SIVGA SM100.
• HIFIXAUDIO 7Hz — biggest strength: Balanced, studio-grade tuning from a 10mm metal-composite dynamic driver, plus a stainless steel faceplate, 0.78mm 2-pin detachable cable and a Type-C-with-mic variant for calls and gaming.
• HIFIXAUDIO 7Hz — biggest trade-off: The body is plastic, and passive noise cancellation only goes so far — it won't mute a noisy commute the way active noise cancelling would.
• SIVGA SM100 — biggest strength: A dual-chamber 10mm driver with a PU + ceramic diaphragm in a high-density zinc alloy shell, tuned for solid mids and powerful bass with reduced vibration distortion.
• SIVGA SM100 — biggest trade-off: No active noise control and no stated mic/control standard beyond push-button controls — it's a music-first earphone with basic call handling.
• Who the 7Hz is for: Buyers who want a balanced, detail-first sound and flexible connectivity (3.5mm and a Type-C-with-mic option) for music, work and gaming.
• Who the SM100 is for: Listeners who want warmth and bass weight, an around-ear cable routing that fights microphonics, and a denser metal build.
The 7Hz Salnotes Zero is built around a single 10mm dynamic driver with a metal-composite diaphragm. In plain terms, that's a stiff, light diaphragm that's meant to move quickly and cleanly, which is why the company describes it as precise and vibrant rather than thick or boomy. The stated frequency range runs from 10Hz to 20kHz, so it reaches low, and the tuning is described as balanced and studio-grade — the kind of presentation that puts vocals and instruments on an even footing instead of pushing one forward.
Impedance is 32 ohm and sensitivity is 108dB, which tells you it's an easy load for a phone, laptop or desktop to drive. You don't need a dedicated amp to get usable volume out of it. The housing combines a plastic body with a stainless steel faceplate — a deliberate split that keeps weight down while adding rigidity where the driver actually sits. The ergonomic shape is described as precision-engineered for a secure fit, and the whole package is aimed at long listening sessions rather than a quick ten-minute listen.
Who should buy it: Anyone who wants a neutral, detail-forward earphone for music, podcasts, work calls and gaming, and who values a replaceable cable and a mic option.
Who should skip it: If you want a big, warm bass shelf or you need serious isolation on a loud train, the balanced tuning and passive-only noise cancellation won't be the priority you're after.
SIVGA SM100: Who It's For
The SM100 takes a different route. Its 10mm driver uses a dual-chamber design with a PU + ceramic composite diaphragm, which the brand says delivers fast response, detailed highs, solid mids and powerful bass while reducing vibration distortion. That's a warmer, more consumer-friendly tuning than the 7Hz. The frequency range goes from 20Hz all the way to 40,000Hz — well beyond what human hearing covers, but a sign the design targets treble extension and air rather than a rolled-off top end.
The housing is high-density zinc alloy, and that's not just cosmetic. A denser shell resists resonance, which SIVGA says gives a more stable acoustic environment, tighter bass and better overall resolution. It's silver, and it feels like a metal earphone in the hand rather than a plastic one. Impedance is 27 ohm and sensitivity is 107dB, so again, it's easy to drive from a phone or laptop without extra gear.
The fit is the other headline. The SM100 uses a 3D ear-scanned ergonomic shape with an around-ear structure — the cable routes up and over your ear rather than hanging straight down. That design does two useful things: it holds the earphone more securely during movement, and it cuts the stethoscope effect, that thumping noise you get when a cable rubs against your clothes. For anyone who walks, commutes or works out while listening, that's a real quality-of-life feature. The cable itself is silver-plated copper, chosen for treble extension and cleaner detail, with 0.78mm 2-pin connectors so you can upgrade or replace it later.
There's an HD microphone for calls and push-button controls for play/pause, track skipping and call handling. Noise control is listed as none, so it's passive isolation only — the seal from the eartips is what blocks outside sound.
Who should skip it: If you want the most neutral tuning possible or you specifically need a Type-C connection, the SM100's warmer voicing and wired-only approach won't match that goal.
Side-by-Side: Which Should You Choose?
• Best for neutral, balanced tuning → HIFIXAUDIO 7Hz. The studio-grade tuning and metal-composite diaphragm lean toward accuracy over warmth.
• Best for bass weight and warmth → SIVGA SM100. The dual-chamber driver and zinc alloy housing are aimed at solid mids and powerful bass.
• Best for a metal build → SIVGA SM100. The entire enclosure is high-density zinc alloy, while the 7Hz uses a plastic body with a stainless steel faceplate.
• Best for cable flexibility → HIFIXAUDIO 7Hz. It offers both a 3.5mm jack and a Type-C-with-Mic option, whereas the SM100 is wired with 2-pin connectors only.
• Best for a secure, low-noise fit → SIVGA SM100. The around-ear structure reduces the stethoscope effect and holds the earphone in place.
• Best for gaming and calls on a computer → HIFIXAUDIO 7Hz. The mic variant with inline media controls is the more plug-and-play choice for a laptop or desktop.
• Best for extended listening comfort → tie, for different reasons. The 7Hz keeps weight down with its plastic body; the SM100 spreads pressure with its ear-scanned around-ear shape.
• Best for easy driving from a phone → either. At 32 ohm / 108dB and 27 ohm / 107dB, both are light loads that a phone can handle.
If I had to pick one, I'd take the HIFIXAUDIO 7Hz. In my opinion, the balanced tuning, the stainless steel faceplate and the dual connectivity — including a Type-C-with-mic version — make it the more versatile earphone for the way most people actually listen: music at a desk, calls on a laptop, gaming in the evening. The SIVGA SM100 is the better pick if you specifically want warmth, bass presence and an around-ear fit that fights cable noise — and its zinc alloy build is genuinely appealing. But as an all-rounder for mixed use, the 7Hz edges it. Check the current price on Amazon before you decide, since both sit in a similar budget-IEM category.
FAQ
Yes. The 7Hz uses a 0.78mm 2-pin cable with gold-plated connectors and 4-core oxygen-free copper wiring. The SM100 uses 0.78mm 2-pin connectors with a silver-plated copper cable. Both let you swap or upgrade the cable later.
The HIFIXAUDIO 7Hz, mainly because of its Type-C-with-Mic variant and inline media controls, which make it easy to use with a phone, laptop or desktop. The SIVGA SM100 does have an HD microphone and push-button controls, so it handles calls too — it's just less focused on that use case.
No. The 7Hz lists passive noise cancellation, and the SM100 lists no noise control at all. Any isolation you get comes from the eartip seal and the fit, not from electronics.
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