Goldwood GW-1858 - 18" Open Baffle Woofer
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Goldwood GW-1858 - 18" Open Baffle Woofer
The Goldwood GW-1858 is an 18" (457 mm) diameter woofer with a nominal impedance of about 6 ohms. The Goldwood woofer has a high Qts and thus works very well with open baffle speaker designs. We have found the Goldwood GW-1858 to be a cost effective and solid performing open baffle woofer. Once placed in a suitably open baffle the Goldwood GW-1858 woofer can produce excellent bass output down below 30 Hz. The Goldwood GW-1858 woofer is available for purchase from Parts Express.
Photograph 1: Goldwood GW-1858 - High Sensitivity 18-inch Open Baffle Woofer
The Goldwood GW-1858 woofer driver utilizes a black poly laminated paper cone and a solid composition paper dust cap. The speakers feature an accordion paper surround. The nominal impedance is 6 ohms and the DCR is noted as 5.3 ohms. The Goldwood GW-1858 woofer voice coil diameter is 63 mm (2.5") and uses a vented pole piece. The datasheet notes the woofer power rating at 220W. The weight of the ferrite magnet is noted as 1417 g (50 oz.) and the net weight of the Goldwood GW-1858 woofer driver is 5.18 kg (11.4 lbs). The 18" woofer is built around a black pressed steel basket. From the datasheet the Goldwood GW-1858 woofers have a noted usable frequency range of 20 Hz to 6 kHz. The woofer excursion is small, noted as Xmax = 2.0 mm. Despite the small excursion, the woofer can play loud rock music with no issues. The overall build quality of the Goldwood GW-1858 woofer drivers appears to be good. The woofer driver connectors are plain spade / solder terminals. The woofer connector terminals are lightweight and do not seem well suited to repeated and heavy use with spade connectors.
Photograph 2: Goldwood GW-1858 Woofer - Pressed Steel Basket and Ferrite Magnet
Thiele/Small (T/S) Parameters - Goldwood GW-1858 Woofer
The Thiele/Small Parameters of the Goldwood GW-1858 Woofer have been measured using the Dayton Audio Test Systems (DATS). The T/S parameters derived from the small signal speaker testing as well as the parameters noted on the Goldwood GW-1858 Woofer datasheet are summarized in Table 1 below. The measured Thiele/Small parameters of the tested woofer pair were generally close to the specifications noted on the Goldwood GW-1858 Woofer datasheet.
Table 1: Thiele/Small (T/S) Parameters - Goldwood GW-1858 Woofers
| Parameter | Goldwood | Woofer 1 | Woofer 2 |
| Fs | 30.28 Hz | 27.59 Hz | 29.61 Hz |
| Vas | 523.8 L | -- | -- |
| Qts | 1.1 | 1.27 | 1.24 |
| Qes | 1.3 | 1.78 | 1.68 |
| Qms | 6.7 | 4.47 | 4.80 |
| Le | 0.6 mH | 0.41 mH | 0.41 mH |
| Re | 5.3 Ohms | 5.52 Ohms | 5.52 Ohms |
| Sensitivity | 94.3 dB/1W/1m | 94.5 dB/1W/1m | 94.5 dB/1W/1m |
Goldwood GW-1858 Woofer Testing Notes:
- Temperature = 20.5 C, Relative Humidity = 52%.
- Le measured at 10kHz.
- Sensitivity measured at 125 Hz.
Figure 1 shows the frequency and impedance response from the Goldwood GW-1858 woofer product literature.
Figure 1: Frequency and Impedance Response - Goldwood GW-1858 Woofer (product literature)
Figure 2 shows the superimposed impedance response of the measured pair of Goldwood GW-1858 woofers. The pair of Goldwood GW-1858 woofers are well broken-in and match reasonably well with each other. The impedance measurements of the Goldwood GW-1858 woofers were determined using the simple to use USB Dayton Audio Test System (DATS).
Figure 2: Impedance Response - Goldwood GW-1858 Woofers
Specifications and Response Graphs - Goldwood GW-1858 Woofer
- Goldwood GW-1858 Woofer Specifications - (PDF 55k)
- Goldwood GW-1858 Woofer Frequency and Impedance Response Graphs - (PDF 209k)
H-Frame Open Baffle Speakers with Goldwood GW-1858 Woofer
The Goldwood GW-1858 woofer has a small motor relative to the woofer size and the resulting high Qts makes the woofer very well suited for use with open baffle style speaker systems. Martin J. King has done some excellent work with the Goldwood GW-1858 (see the links included at the bottom of this page) and found it to be a well performing and economical open baffle woofer that can produce strong bass output down to below 30 Hz. Because of the good open baffle speaker performance and low cost for the GW-1858 woofer, this is one of the more popular woofers for open baffle speaker systems. Mounted in an H-Frame open baffle the GW-1858 woofer is quick, accurate, clean and musical. The woofer is an easy to drive 6 ohm load and will deliver clean, tight, crisp bass provided that the driver excursion is not exceeded.
Photograph 3: Goldwood GW-1858 Woofer on H-Frame Open Baffle
In Photograph 3 the 18" diameter Goldwood GW-1858 woofer is mounted in a 508 mm (20") H-Frame open baffle and paired with a Audio Nirvana Classic 8 fullrange driver and fashioned after the Open Baffle with a Goldwood GW-1858 Woofer H Frame Project by Martin J. King. An active crossover is used and the crossover point is set at about 175 Hz. The silver tweeter shown in the photo is a Radio Shack 40-1310 external horn super tweeter which is used to provide a little air and sparkle above about 12kHz.
With the Goldwood GW-1858 woofer in the H-frame open baffle we were able to achieve an in-room F3 of about 33 Hz and an F10 of about 25 Hz. Overall, the GW-1858 open baffle woofers sound fantastic. In the H-frame open baffle the GW-1858 woofers provide natural sounding deep bass that is clean and crisp and without boominess. At under $100 for an 18" woofer, the Goldwood GW-1858 is an excellent value for providing deep bass from a simple open baffle speaker.
Similar open baffle woofers used: Eminence Alpha-15A - 15" Woofer.
The Goldwood GW-1858 18" Open Baffle Woofer is available for purchase from Parts Express.
Open Baffle Projects Links - Goldwood GW-1858 Woofer
- Jordan JX92S Open Baffle with a Goldwood GW-1858 Woofer in an H Frame Project - [External Link]
- Comparison of the Bass Performance of Passive Open Baffle, U Frame, and H Frame Speakers - (PDF 117k)