Overview

The Neumann KMS 104 Plus is a studio-grade handheld condenser microphone designed specifically for vocal applications, particularly optimized for female voices in rock and pop contexts. Unlike typical stage microphones that use dynamic capsules, the KMS 104 Plus features Neumann’s true condenser capsule technology, offering the clarity that has made Neumann studio microphones renowned worldwide. This Plus variant provides extended bass response compared to the standard KMS 104, with added emphasis in the 100-150 Hz range to provide more “weight” and “warmth” to voices. The microphone incorporates a built-in 120 Hz highpass filter to compensate for proximity effect during close miking applications.

Scientific Validity

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The KMS 104 Plus demonstrates mixed measured performance with several specifications at problematic thresholds. The S/N ratio of 76 dB (A-weighted) sits above the 60 dB problematic level but below the 80 dB transparent level for microphones. Maximum SPL capability of 150 dB exceeds the excellent threshold of 140 dB. The dynamic range of 132 dB surpasses the transparent level of 105 dB. The frequency response spans 20 Hz-20 kHz with bass extension optimization, though the 120 Hz highpass filter reduces low-frequency capability. The 50-ohm output impedance enables long cable runs up to 300 meters without losses.

Technology Level

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The KMS 104 Plus utilizes proven Neumann condenser capsule technology with several practical engineering solutions. The true condenser design represents established expertise in electro-acoustic transducer development, featuring transformerless output to minimize electromagnetic interference. The hardened steel headgrille incorporates an effective internal pop screen while protecting the capsule from moisture. The fixed lowcut filter at 120 Hz demonstrates thoughtful proximity effect compensation for close miking applications. The design represents a traditional analog approach common for microphones and is appropriate for this category.

Cost-Performance

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The KMS 104 Plus currently retails for 544 USD and offers true condenser capsule technology in a handheld format with cardioid pattern, 150 dB maximum SPL, 76 dB S/N ratio (A-weighted), 132 dB dynamic range, and specialized bass extension with 120 Hz highpass filter. The closest equivalent alternative is the Audio-Technica AE5400, a handheld condenser microphone providing cardioid pattern, 20 Hz-20 kHz frequency response, 147 dB maximum SPL (157 dB with pad), 14 dB self-noise equivalent to approximately 80 dB S/N ratio, built-in 80 Hz HPF and 10 dB pad switches [6]. Equipped with equivalent handheld condenser functionality and comparable measured performance including superior self-noise characteristics, the AE5400 is available for approximately 269 USD [7]. CP = 269 USD ÷ 544 USD = 0.5. The AE5400 provides equivalent handheld condenser functions with competitive specifications at substantially reduced cost.

Reliability & Support

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Neumann provides exceptional long-term support with service available for all microphones manufactured after 1947, demonstrating unparalleled commitment to product longevity. The company maintains a global service network with specialized microphone expertise and offers restoration to original specifications using archived production drawings. The simple analog construction with hardened steel housing and few moving parts creates inherent resistance to failure. Neumann recommends inspection every 3-5 years for optimal performance and can remanufacture mechanical components when needed. The microphone undergoes extensive quality control with up to 50 different tests performed on capsules before final assembly. However, the warranty period remains standard rather than exceptional, preventing a higher reliability score despite the strong support infrastructure.

Rationality of Design Philosophy

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The KMS 104 Plus represents traditional high-quality microphone engineering with a scientific approach to condenser capsule design, though it demonstrates limitations in cost optimization and modern technology integration. The analog approach is standard for microphones, with functionality focused on robust, stage-ready performance. The proximity effect compensation through the 120 Hz filter demonstrates rational acoustic engineering for its intended handheld vocal application. The design philosophy balances traditional construction quality with specific application optimization, though the significant cost premium over equivalent-performing alternatives suggests sub-optimal resource allocation toward user value.

Advice

The KMS 104 Plus serves professional vocalists requiring handheld condenser performance with Neumann’s renowned build quality and long-term support. The extended bass response and proximity effect compensation make it particularly suitable for close-miking applications and female voices in rock/pop contexts. However, potential buyers should carefully consider whether the premium price aligns with their specific needs, as alternatives like the Audio-Technica AE5400 offer competitive measured performance at substantially lower cost. The microphone excels in professional environments where Neumann’s exceptional service legacy and brand reliability justify the premium. For most live performance applications, the AE5400 provides equivalent handheld condenser functionality with competitive specifications at approximately half the cost, making the KMS 104 Plus primarily justified when Neumann’s specific sonic character and long-term support commitment are essential requirements.

References

1. Neumann, “KMS 104 Plus Stage Microphone,” Official Product Page, https://www.neumann.com/en-us/products/microphones/kms-104-plus, accessed September 2025
2. RecordingHacks, “Neumann KMS 104 Plus Specifications,” http://recordinghacks.com/microphones/neumann/kms-104-plus, accessed September 2025
3. AudioTechnology, “Review: Neumann KMS 104 Plus,” https://www.audiotechnology.com/reviews/neumann-kms-104-plus, accessed September 2025
4. Full Compass, “Neumann KMS 104 PLUS Specifications,” https://www.fullcompass.com/prod/287052-neumann-kms-104-plus-cardioid-condenser-stage-microphone-for-vocals-plus-extended-bass-response, accessed September 2025
5. Sweetwater, “Neumann KMS 104 Plus Handheld Condenser Microphone,” https://www.sweetwater.com/store/detail/KMS104Plus–neumann-kms-104-plus-handheld-condenser-microphone, accessed September 2025
6. Audio-Technica, “AE5400 Cardioid Condenser Handheld Microphone,” Official Product Page, https://www.audio-technica.com/en-us/ae5400, accessed September 2025
7. Sweetwater, “Audio-Technica AE5400 Handheld Condenser Microphone,” https://www.sweetwater.com/store/detail/AE5400–audio-technica-ae5400-handheld-condenser-microphone, pricing accessed September 2025

(2025.9.11)