1. Introduction
The RCF MR8N301 is an 8-inch high-efficiency, high-power midrange speaker engineered to deliver superior sound pressure levels within a compact design. Its construction features a powerful neodymium magnet assembly, significantly reducing the overall weight compared to similar ceramic midrange speakers. The unique sealed basket design eliminates the need for external back sealing chambers, simplifying cabinet integration and enhancing heat dissipation. This speaker is optimized for precise reproduction and control of midrange frequencies.
2. Product Features
- Voice Coil: 3-inch, inside/outside copper voice coil for enhanced performance.
- Power Handling: 400W continuous program power handling.
- Sensitivity: 107 dB sensitivity in horn-loaded applications.
- Frequency Range: 300 Hz – 3 kHz frequency response.
- Magnet Design: High BL neodymium magnet design.
- Basket Design: Unique aluminum sealed basket with vented fin heat dissipation.
- Calibrated Back Volume: Ensures accurate time domain transient reproduction.
3. Technical Specifications
General Specifications
| Parameter | Value |
|---|---|
| Nominal Diameter | 8 inch / 203 mm |
| Rated Impedance | 8 ohm |
| Program Power | 400 W |
| Power Handling Capacity | 200 W |
| Sensitivity | 102.0 dB |
| Frequency Range | 300 - 3000 Hz |
| Effective Piston Diameter | 168 mm / 6.61 inch |
| Max. Excursion Before Damage | 15 mm / 0.59 inch |
| Minimum Impedance | 9.8 ohm |
| Voice Coil Diameter | 3.0 inch / 76 mm |
| Voice Coil Winding Material | Aluminum |
| Voice Coil Length | 11 mm / 0.43 inch |
| Number of Layers | 2 (inside/outside) |
| Top Plate Thickness | 8 mm / 0.31 inch |
| Cone Design | Curved |
| Surround Material | Polycotton |
| Surround Design | Triple roll |
| Magnets | Neodymium |
| Spider | 1 |
Thiele-Small Parameters
| Parameter | Value |
|---|---|
| Resonance Frequency (Fs) | 310 Hz |
| DC Resistance (Re) | 6.60 ohm |
| Mechanical Factor (Qms) | 3.45 |
| Electrical Factor (Qes) | 0.41 |
| Total Factor (Qts) | 0.37 |
| Bl Factor (Bl) | 17.80 T x m |
| Effective Moving Mass (Mms) | 10.0 g |
| Equivalent Cas Air Loaded (Vas) | 2.0 liters |
| Effective Piston Area (Sd) | 0.020 m² |
| Max. Linear Excursion (Xmax) | 4 mm |
| Voice Coil Inductance @ 1kHz (Le1k) | 1.16 mH |
| Half-space Efficiency (Eff) | 0.128 |
4. Setup and Mounting Information
Proper mounting is crucial for optimal performance and longevity of your RCF MR8N301 speaker. Refer to the dimensions below for accurate cabinet design and installation.
Physical Dimensions
| Parameter | Value |
|---|---|
| Overall Diameter | 238 mm / 9.37 inches |
| Bolt Circle Diameter | 220 mm / 8.66 inch |
| Bolt Hole Diameter | 7 mm / 0.28 inch |
| Front Mount Baffle Cut-out | 202 mm / 7.95 inch |
| Rear Mount Baffle Cut-out | 187 mm / 7.36 inch |
| Volume Occupied by Driver | 2 liters / 0.08 ft³ |
| Height | 111 mm / 4.37 inches |
| Diameter | 208 mm / 8.19 inches |
| Weight | 3.31 kg / 7.3 lbs |
Installation Steps:
- Prepare the Enclosure: Ensure your speaker enclosure is constructed to the specified dimensions, allowing for proper fit and acoustic performance.
- Cut-out: Use the provided front or rear mount baffle cut-out dimensions to create the opening in your enclosure.
- Mounting: Secure the speaker using appropriate screws through the bolt holes. Ensure a tight seal to prevent air leaks, which can negatively impact sound quality.
- Wiring: Connect the speaker to your amplifier or crossover network, observing correct polarity (+ to + and - to -). Incorrect polarity can lead to phase issues and degraded sound.
Figure 1: Top view of the RCF MR8N301 speaker, showing the cone and mounting holes.
Figure 2: Angled view of the RCF MR8N301, highlighting the compact design and sealed basket.
5. Operating Instructions
Once installed and wired correctly, the RCF MR8N301 midrange speaker is ready for operation. Follow these general guidelines:
- Power Matching: Ensure your amplifier's power output is within the speaker's rated power handling capacity (200W RMS, 400W Program Power). Overpowering can cause damage.
- Crossover Settings: For optimal sound and speaker protection, use an appropriate crossover network. The recommended frequency range for this speaker is 300 Hz to 3 kHz. Set your high-pass filter above 300 Hz and your low-pass filter below 3 kHz.
- Volume Control: Gradually increase the volume to avoid sudden peaks that could stress the speaker. Listen for any signs of distortion and reduce volume if detected.
- Break-in Period: New speakers may benefit from a break-in period of several hours of moderate-level playback to allow the suspension components to loosen and achieve optimal performance.
6. Care and Maintenance
To ensure the longevity and continued performance of your RCF MR8N301 speaker, observe the following care and maintenance practices:
- Cleaning: Use a soft, dry cloth to gently wipe dust from the speaker cone and frame. Avoid using harsh chemicals or abrasive materials.
- Environmental Conditions: Protect the speaker from extreme temperatures, direct sunlight, and high humidity. While the speaker is robust, these conditions can degrade materials over time.
- Physical Protection: Avoid touching the speaker cone or surround with your hands or other objects, as this can cause damage.
- Storage: If storing the speaker for an extended period, keep it in a cool, dry place, ideally in its original packaging or a protective cover.
7. Troubleshooting
If you encounter issues with your RCF MR8N301 speaker, consider the following common troubleshooting steps:
- No Sound:
- Check all wiring connections from the amplifier/crossover to the speaker for secure contact and correct polarity.
- Verify that the amplifier is powered on and functioning correctly.
- Ensure the audio source is active and sending a signal.
- Distorted Sound:
- Reduce the volume level. Distortion often occurs when the amplifier or speaker is overdriven.
- Check crossover settings to ensure they are appropriate for the midrange speaker's frequency range.
- Inspect the speaker cone and surround for any visible damage.
- Weak or Uneven Sound:
- Confirm correct wiring polarity for all speakers in your system.
- Ensure the speaker is properly mounted and sealed within its enclosure.
If these steps do not resolve the issue, consult a qualified audio technician.
8. Package Contents
The RCF MR8N301 package includes:
- 1 x RCF-MR8N301 8-inch Midrange Speaker (8-Ohm)
9. Warranty and Support
RCF products are manufactured to high standards and undergo rigorous quality control. For specific warranty details and support inquiries, please refer to the warranty card included with your product or visit the official RCF website. Keep your purchase receipt as proof of purchase for any warranty claims.
