Short answer: the Violectric HPA V550 PRO for better measured performance, the Soncoz SGA1 for the lower price. The Violectric HPA V550 PRO ranks #11 of 19 headphone amplifiers, rated 4.6/5, at $3,599.99. The Soncoz SGA1 ranks #12, rated 4.5/5, at $649.99, $2,950 cheaper.
What the Violectric HPA V550 PRO does well: Violectric rates it at 4,700 mW into 32 ohms and 1,450 mW into 300 ohms, enough to drive nearly any headphone, and Audio Science Review measured a SINAD of 111 dB, clean for nearly all listening. The tradeoff: The Topping A50 III rates higher and measured cleaner in Audio Science Review’s tests for a small fraction of the price.
Why pick the Soncoz SGA1: Audio Science Review measured 118 dB SINAD, so its noise and distortion are inaudible. The tradeoff: It is an analog only amp with no digital inputs, so you need a separate DAC.
Buy the Violectric HPA V550 PRO if measured performance is the priority over the price, or the Soncoz SGA1 if the price is the priority over measured performance.
Looking for alternatives? See the complete Headphone Amps and DACs rankings.
Specifications Side By Side
| Violectric HPA V550 PRO | Soncoz SGA1 | |
|---|---|---|
| Price | $3,599.99 | $649.99 |
| Ranked | #11 of 19 in Headphone Amplifiers | #12 of 19 in Headphone Amplifiers |
| Device Type | Headphone amp | Headphone amp |
| SINAD | 111 dB (measured by Audio Science Review) | 118 dB (measured by Audio Science Review) |
| Output Power (32 ohms) | 4,700 mW (manufacturer rated) | 420 mW (manufacturer rated at 33 ohms, balanced) |
| Output Power (300 ohms) | 1,450 mW (manufacturer rated) | 840 mW (manufacturer rated, balanced) |
| Headphone Outputs | 6.35 mm, 4-pin XLR balanced, 4.4 mm balanced | 6.35 mm, 4-pin XLR balanced, 4.4 mm balanced |
| Balanced Output | Yes (4-pin XLR, 4.4 mm, XLR line out) | Yes (4-pin XLR, 4.4 mm, XLR line out) |
| Inputs | 2 x RCA, XLR | RCA, XLR |
| Outputs | RCA, XLR | RCA, XLR |
| Volume Control | Hardware knob (256-step relay attenuator, remote) | Electronic stepped volume (MUSES72320) |
| Dimensions | 11.4” x 3.1” x 9.8” (290 x 80 x 248 mm) | 9.8” x 2.2” x 8.9” (250 x 55 x 225 mm) |
| Weight | - | 4.4 lbs (2,000 g) |
Related Amp and DAC Comparisons
More top alternatives to Violectric HPA V550 PRO:
- Topping A90 Discrete vs Violectric HPA V550 PRO
- SMSL VMV P2 vs Violectric HPA V550 PRO
- Tom Christiansen Audio HPA-1 vs Violectric HPA V550 PRO
- Violectric HPA V550 PRO vs Benchmark HPA4
- Violectric HPA V550 PRO vs Chord Alto
Prices on this page were last checked October 11, 2026 at 4:59 PM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.
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The Two Amps and DACs In Full
Violectric HPA V550 PRO: $3,599.99 Amazon eBay
Pros: Violectric rates it at 4,700 mW into 32 ohms and 1,450 mW into 300 ohms, enough to drive nearly any headphone, and Audio Science Review measured a SINAD of 111 dB, clean for nearly all listening. It offers 6.35 mm, 4-pin XLR and 4.4 mm balanced headphone outputs, RCA and XLR inputs and outputs, and a 256-step relay volume control with a remote.
Cons: The Topping A50 III rates higher and measured cleaner in Audio Science Review’s tests for a small fraction of the price. It is an analog amp only, so you still need a separate DAC.
Full Violectric HPA V550 PRO review and specifications →
| Balanced Output | Yes (4-pin XLR, 4.4 mm, XLR line out) |
|---|---|
| Device Type | Headphone amp |
| Dimensions | 11.4” x 3.1” x 9.8” (290 x 80 x 248 mm) |
| Headphone Outputs | 6.35 mm, 4-pin XLR balanced, 4.4 mm balanced |
| Inputs | 2 x RCA, XLR |
| Output Power (300 ohms) | 1,450 mW (manufacturer rated) |
| Output Power (32 ohms) | 4,700 mW (manufacturer rated) |
| Outputs | RCA, XLR |
| SINAD | 111 dB (measured by Audio Science Review) |
| Volume Control | Hardware knob (256-step relay attenuator, remote) |
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
Soncoz SGA1: $649.99 HiFiGo eBay
Pros: Audio Science Review measured 118 dB SINAD, so its noise and distortion are inaudible. It offers 6.35 mm, 4-pin XLR and 4.4 mm balanced headphone outputs, RCA and XLR inputs and outputs, and a stepped electronic volume control, with 840 mW into 300 ohms for high impedance headphones.
Cons: It is an analog only amp with no digital inputs, so you need a separate DAC. Soncoz rates it at 420 mW balanced into 33 ohms rather than 32, which drives most headphones but is modest next to the Topping L30, a higher rated amp that costs far less.
Full Soncoz SGA1 review and specifications →
| Balanced Output | Yes (4-pin XLR, 4.4 mm, XLR line out) |
|---|---|
| Device Type | Headphone amp |
| Dimensions | 9.8” x 2.2” x 8.9” (250 x 55 x 225 mm) |
| Headphone Outputs | 6.35 mm, 4-pin XLR balanced, 4.4 mm balanced |
| Inputs | RCA, XLR |
| Output Power (300 ohms) | 840 mW (manufacturer rated, balanced) |
| Output Power (32 ohms) | 420 mW (manufacturer rated at 33 ohms, balanced) |
| Outputs | RCA, XLR |
| SINAD | 118 dB (measured by Audio Science Review) |
| Volume Control | Electronic stepped volume (MUSES72320) |
| Weight | 4.4 lbs (2,000 g) |
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- Soncoz SGA1 vs Benchmark HPA4
- Soncoz SGA1 vs Little Labs Monotor
- Soncoz SGA1 vs Tom Christiansen Audio HPA-1
- Soncoz SGA1 vs Rupert Neve Designs RNHP
- Soncoz SGA1 vs SMSL VMV P2
- Soncoz SGA1 vs HeadAmp Gilmore Lite Mk2
- Soncoz SGA1 vs Topping A90 Discrete
- Soncoz SGA1 vs Topping A70 Pro
- See all 9 comparisons