Raven-XT2 (the Final Cut)


I first worked on the Raven in 2017. That was the first time I had a feel of the Dayton RS180s-08 with the Peerless XT25TG30-04. This Raven-XT2 is he final version. It has a flatter frequency response and a more elegant crossover.

The challenge with the Raven-XT2 is in the management of the Dayton RS180s-08 midwoofer.

Fig 1 – Dayton RS180s RAW Response • Baffle Width=8-1/2″

The plot in Fig 1 is the RAW response of the RS180s-08. The cone breakup spikes is enough to scare most diyers away. The easiest way to use this midwoofer is cross it at about 125Hz to 800Hz. In doing so, you’ll avoid the breakup spikes from 7kHz upwards. Another issue with the RS180s is the early roll-off. At 1.5kHz, it starts to roll off, making it difficult to cross at 2.5kHz.

Fig 2 – RS180s with Low Pass Filer (LPF)

After making some adjustments, I managed to get the RS180s-08 to roll off the way I wanted (Fig 2 – Blue plot). My targeted crossover frequency is 2.5kHz. As for the sharp spikes, I did not use any notch filters as they are already down by -18dB. Should they interfere with the treble, I will have to EQ them out. I am hesitant to do that because of the extra cost, so I’m hoping -18dB is sufficient to suppress those offensive peaks.

Fig 3 – Blue plot=Dayton RS180s-08 with LPF • Peerless XT25TG30-04 with HPF

Fig 3 shows the midwoofer and tweeter responses with their respective networks. It’s encouraging that the RS180s and the XT25TG30 are crossing at about 2.5kHz.

Fig 4 – Raven-XT2 Passband

The Black plot in Fig 4 is the Raven-XT2 crossover passband. I’m quite pleased with the summation as there are no signs of cancellations in the passband. More than that, I’m not seeing the RS180s spikes protruding in the upper treble.

Fig 5 – Raven-XT2 Frequency Response

Fig 5 is the Frequency Response of the Raven-XT2. This is an incredibly flat response, all the way to 20kHz. 

Fig 6 – Raven-XT2 Null Response

The Raven-XT2 null is not as sharp as I would like. The null center is at 2.5kHz, which is a positive indication. However, the lack of depth shows that the two drivers are not locked in exactly at 2.5kHz. I will leave it for the time being. If I cannot hear any phasing issues, then it’s fine.

Fig 7 – Raven-XT2 Step Response

The Step Response in Fig 7 doesn’t show anything amiss with the Raven-XT2. 

Fig 8 – Raven-XT2 Waterfall

The Waterfall plot in Fig 8 shows an exceptionally clean treble. 

Fig 9 – Raven-XT2 Toneburst Energy Storage

The Toneburst plot in Fig 9 shows stored energy emitting from 1.5kHz. It appears that there’s some ringing in the RS180s.

Fig 10 – Raven-XT2 Spectrogram

The Raven-XT2 Spectrogram shows some hot spots at 1.2kHz and 1.4kHz. These are the light blue slices at 1.5kHz seen in Fig 9. I doubt I’ll hear any smearing in the vocals because most of the energy is dissipated by 6 msec.

Fig 11 – Raven-XT2 Harmonic Distortion • RED plot=2nd Harmonics • VIOLET plot=3rd Harmonics

The 3rd harmonics (Violet plot in Fig 11) is lower than most. It’s about -60dB below the fundamental. The 2nd harmonics (Red plot) and the THD (Blue plot) are at -50dB. With such low distortion, I do not expect to be irritated by the Raven-XT2.

Sound of Raven-XT2

The Dayton RS180s-08 is not a friendly woofer to work with but if she is tamed, she can sound excellent. In the Raven-XT2, I am more than pleased with her performance. There’s a certain liveliness about her that makes the Raven-XT2 more realistic. Coupled that with a decent bass punch, the Raven-XT2 outperforms other speakers in that price range.

Fig 12 – Raven-XT2 In-Room Response

An indication of the bass volume can be seen in Fig 12. Disregard the suck-out at 150Hz. That’s caused by a floor bounce in my setup. The bass region from 100Hz to 65Hz is level with the fundamental (85dB). This was taken with the Raven-XT2 in Full Space (4 pi). No bass boost is necessary unless one is a basshead.

As for the spikes during the cone breakup, I couldn’t hear any brittleness in the treble. Neither could I pick out phasing issues in the crossover. Time alignment can be done but it would only add to the cost and complexity of the crossover with no audible gain.

Crossover is available on request. Free for DIY. Not for Commercial use.
Unless otherwise stated, all measurements were made with the mic at 36 ins, tweeter axis. Impulse Window=5ms. No smoothing applied.