SKU: 18651Category: Phono StagesAvailability: in stock
749,00 €
sPQ-100 is a phono equalizer built with circuits that amplify very fine signals hundreds to thousands of times, and allow you to select a phono EQ with various characteristics based on SOtM’s special noise reduction technology.
The SOtM sPQ-100 Phono Stage brings the South Korean manufacturer’s precision engineering philosophy to the world of vinyl playback.
Designed for both Moving Magnet (MM) and Moving Coil (MC) cartridges, the sPQ-100 combines flexible cartridge loading, four selectable gain settings and an unusually comprehensive set of phono equalization controls.
Its advanced adjustment capabilities allow listeners to match the phono stage to a wide variety of cartridges and select different playback equalization characteristics for records from different periods.
For enthusiasts who value the musical character of analogue recordings, the sPQ-100 offers an exceptional level of flexibility in a compact high-end component.
SOtM’s Approach to Analogue Audio
SOtM is widely recognised for its dedicated digital audio products, including network streamers, USB interfaces, Ethernet switches and precision clock systems.
Behind these technologies lies extensive experience in analogue circuit design, power regulation and electrical-noise management.
The sPQ-100 brings this experience into a different but equally demanding application: the amplification and equalization of the tiny electrical signals generated by phono cartridges.
A moving-coil cartridge can produce an output of only a few tenths of a millivolt. This delicate signal must be amplified substantially while retaining musical detail and controlling unwanted noise.
SOtM developed the sPQ-100 around this challenge, combining flexible adjustment with the manufacturer’s emphasis on carefully engineered low-noise circuitry.
Designed for MM and MC Cartridges
The SOtM sPQ-100 supports both Moving Magnet and Moving Coil phono cartridges.
Because different cartridges have different output voltages, internal impedances and loading requirements, a flexible phono preamplifier can offer practical benefits when matching a cartridge to an audio system.
The sPQ-100 provides dedicated MM/MC selection together with adjustable input loading and gain.
The appropriate settings should be chosen according to the cartridge manufacturer’s recommendations and the requirements of the connected amplifier.
Flexible Moving Magnet Loading
For Moving Magnet cartridges, the manufacturer specifies an input resistance of 47kΩ together with selectable capacitance settings.
Available capacitance options are:
100pF
150pF
220pF
330pF
Capacitance can influence the frequency response of a moving-magnet cartridge, particularly when combined with the capacitance of the tonearm cable.
Proper matching therefore requires consideration of both the phono stage and the cabling between the turntable and phono input.
Moving Coil Cartridge Loading
For Moving Coil cartridges, the sPQ-100 offers a range of selectable input resistances:
15Ω
20Ω
100Ω
500Ω
The manufacturer’s specification also identifies a 10pF input capacitance value for MC operation.
These resistance settings allow the phono stage to accommodate many low-output MC cartridges, subject to their individual electrical requirements.
Correct loading should be determined using the cartridge manufacturer’s guidance and verified through careful listening where appropriate.
Four Selectable Gain Settings
The sPQ-100 provides four selectable levels of total gain, measured at 1kHz:
40dB
50dB
60dB
70dB
This wide gain range is especially useful when working with cartridges of different output levels.
A typical high-output MM cartridge may require substantially less amplification than a low-output MC cartridge.
With gain adjustment, the sPQ-100 can be configured to achieve an appropriate signal level while avoiding unnecessary amplification or overload.
The best setting depends on cartridge output, the input sensitivity of the following amplifier and the desired playback level.
More Than a Conventional RIAA Phono Stage
One of the most distinctive capabilities of the SOtM sPQ-100 Phono Preamplifier is its adjustable equalization system.
Modern stereo vinyl records are generally reproduced using the standard RIAA playback equalization curve.
However, historically, record manufacturers employed different recording equalization characteristics, particularly before the widespread adoption of RIAA standardization.
The sPQ-100 provides separate controls for important parts of the playback EQ response.
These include bass boost level, bass turnover frequency and high-frequency roll-off frequency.
Rather than restricting the listener to one fixed equalization characteristic, this approach allows different response settings to be selected according to the record and the intended playback curve.
Adjustable Bass Boost
The manufacturer specifies four bass boost selections:
14.5dB at 20Hz
16dB at 20Hz
20dB at 20Hz
33dB at 7Hz, without bass shelf
These options form part of the phono equalization network.
They should not be confused with a conventional bass tone control, as their function is related to the overall playback EQ characteristics.
Adjustable Bass Turnover Frequency
The bass turnover controls provide four frequency selections:
250Hz
354Hz
500Hz
800Hz
The turnover setting influences the low-frequency transition of the playback equalization curve.
Different selections can be used as part of the process of matching historic recording equalization characteristics.
Adjustable High-Frequency Roll-Off
The sPQ-100 also offers four high-frequency roll-off frequency selections:
1592Hz
2122Hz
2500Hz
3183Hz
Combined with the bass controls, these settings give the listener extensive flexibility in configuring the playback response.
For normal RIAA playback, the appropriate switch combination should be selected according to the manufacturer’s operating instructions.
For older records using alternative equalization standards, the required curve should be identified before changing the settings.
Exploring Historic Vinyl Recordings
Collectors of early LPs, mono recordings and other historic disc formats may encounter recordings made using different equalization conventions.
The sPQ-100 offers the flexibility to adjust key playback EQ parameters rather than relying exclusively on a fixed RIAA characteristic.
This makes it particularly interesting for listeners who maintain collections spanning different recording eras.
However, a suitable cartridge and turntable configuration must also be used for the record format being played.
Important: Selecting a different equalization curve does not automatically make a modern stereo cartridge suitable for every historic or 78rpm record. Stylus profile, tracking requirements and turntable speed must also be appropriate.
Convenient Top-Panel Adjustment
The adjustment controls are located on the top of the sPQ-100 chassis.
This arrangement allows the listener to configure cartridge type, input loading, gain and equalization settings through dedicated selection switches.
The available controls include:
MM/MC cartridge selection
Input impedance and capacitance
Bass boost level
Bass turnover frequency
High-frequency roll-off frequency
Total gain
Always follow the operating instructions when changing settings. Where required, power down the system or mute the amplifier to avoid switching noise reaching the loudspeakers.
Low-Noise Analogue Circuit Design
Phono amplification is one of the most demanding applications in high-fidelity audio because the input signal is exceptionally small.
The amplifier must increase this signal by hundreds or thousands of times while maintaining a low noise floor.
SOtM applies its experience in analogue circuitry and electrical-noise management to the sPQ-100.
The manufacturer’s design objective is to preserve detail, dynamic expression and tonal balance while providing the gain necessary for MM and MC playback.
Actual system performance depends on cartridge matching, grounding, cabling and the rest of the analogue playback chain.
RCA Connections and Turntable Grounding
The sPQ-100 provides stereo RCA phono inputs with an associated earth terminal, together with stereo RCA analogue outputs.
The turntable should be connected using a suitable phono cable, with the turntable ground lead connected where required by the equipment configuration.
Good cable routing and correct grounding are particularly important for low-output Moving Coil cartridges.
The phono stage should be positioned away from strong electromagnetic fields and large power transformers where practical.
External DC Power Supply
The sPQ-100 is powered through an external DC input.
SOtM specifies an input voltage range of 7V to 9V DC and maximum current consumption of 1A.
The DC connection uses a 5.5mm outer diameter and 2.1mm inner diameter barrel jack.
When choosing an alternative power supply, the output voltage, connector polarity, plug dimensions and available current must all match the manufacturer’s requirements.
Potential upgrades should be verified for compatibility rather than selected solely on their nominal voltage rating.
Compact Construction for High-End Systems
The SOtM sPQ-100 is housed in a compact enclosure measuring 106 × 48 × 245mm.
Its relatively small footprint allows installation in audio racks where space is limited.
Despite its dimensions, the sPQ-100 provides a level of cartridge and EQ adjustment normally associated with substantially more complex phono amplification systems.
International Reviews and Recognition
Mono & Stereo | September 2023
Matej Isak reviewed the SOtM sPQ-100, examining its construction, cartridge matching and musical performance.
The product also received the publication’s Highly Recommended recognition, as referenced by SOtM on its official product page.
Greek audio publication HXOS Plus conducted a dedicated evaluation of the sPQ-100, discussing its measurements, equalization flexibility and listening performance.
14.5 / 16 / 20dB at 20Hz
33dB at 7Hz, without bass shelf
Bass Turnover Frequency
250 / 354 / 500 / 800Hz
High-Frequency Roll-Off
1592 / 2122 / 2500 / 3183Hz
Inputs
1 × Stereo RCA, with earth terminal
Outputs
1 × Stereo RCA
Maximum Output Level
9.5V AC
Output Impedance
20Ω typical
Frequency Response
20Hz–20kHz
Signal-to-Noise Ratio
100dB typical, at 1kHz and maximum output level, MC / RIAA / 50dB gain setting
DC Power Input
7–9V DC, maximum 1A
DC Connector
5.5mm OD / 2.1mm ID barrel jack
Operating Temperature
0°C to +40°C
Storage Temperature
0°C to +40°C
Humidity
10–90%
Dimensions
106 × 48 × 245mm
Weight
Approximately 1.5kg
Technical values are based on the manufacturer’s published specifications. Cartridge loading, gain and equalization should be configured according to the operating instructions.
Frequently Asked Questions
Does the SOtM sPQ-100 support MM and MC cartridges?
Yes. It supports both Moving Magnet and Moving Coil cartridges with dedicated loading and gain options.
How many gain settings are available?
Four: 40dB, 50dB, 60dB and 70dB at 1kHz.
What input resistance settings are available for MC cartridges?
15Ω, 20Ω, 100Ω and 500Ω.
What capacitance options are available for MM cartridges?
100pF, 150pF, 220pF and 330pF, together with a nominal 47kΩ input resistance.
Does the sPQ-100 support the RIAA equalization curve?
Yes. It provides adjustable equalization parameters that can be configured for RIAA playback and other appropriate historic playback characteristics.
Can it be used for older vinyl records?
Yes. Its adjustable equalization makes it suitable for exploring recordings using different historic EQ characteristics. The turntable, stylus and cartridge must also be appropriate for the record format.
Can I use it with a low-output MC cartridge?
Many low-output MC cartridges fall within its specified input range of 0.1–1mV. Matching should be confirmed using the cartridge output voltage and recommended loading.
Does it include a headphone amplifier?
No. The sPQ-100 is a phono preamplifier with stereo RCA outputs designed to connect to a suitable line-level input on an amplifier or preamplifier.
Can I connect it to the phono input of an integrated amplifier?
No. Its output should normally connect to a line-level input such as AUX, LINE or CD, rather than another phono input.
Does it require an external power supply?
Yes. The manufacturer specifies 7–9V DC with a maximum input current of 1A.
Can I upgrade the power supply?
Potentially, using an electrically compatible unit. Output voltage, polarity, connector type and current capability must all be checked.
Is it suitable for a high-end turntable?
Yes. The sPQ-100 is designed for use with compatible MM and MC cartridges, and its suitability depends primarily on cartridge matching and the wider audio system.
Are independent reviews available?
Yes. Reviews and tests are available from Mono & Stereo and HXOS Plus.
Why Choose the SOtM sPQ-100?
The SOtM sPQ-100 Phono Stage offers unusual flexibility for listeners who want more than a conventional fixed-RIAA phono preamplifier.
With MM/MC compatibility, extensive cartridge loading options, selectable gain and adjustable playback EQ parameters, it provides a powerful foundation for exploring the full potential of an analogue record collection.
Precision Analogue Engineering. Flexible Equalization. Music from the Groove.
Availability and International Orders
Contact Chameleon Audio for current availability, cartridge compatibility advice, phono cable matching and international shipping options for the SOtM sPQ-100 Phono Stage.
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