Eminence Delta Lite 2512 vs. Pioneer PW-302A

Old vs. New

This article contains music videos to emphasize the importance of listening to music in evaluating audio components. That said, I also pasted the easily missed disclaimer below taken from the 'about' section of my YouTube channel.😉

Having been a professional musician with decades of experience in front of and behind a microphone, given the limitations imposed on sound quality by my recording equipment and this platform, my videos are merely proof of concept and are not intended for sonic evaluation. Hopefully the visual aspect serves as an inspiration to other hobbyists!

My listening tests were conducted entirely in full dimensional monaural high fidelity using the following equipment:

Turntable: Gray Research HF500 

Tonearms: Gray Research 108 or Velvet Touch

Phono Cartridges: Denon DL102 or GE VRII Pro
Phono preamp: DIY 6SL7 phono with variable passive EQ
Line stage: 6AH4GT+ Altec 15095A or triode connected 6C6 + 6SN7 CF

Amp: DIY Western Electric 133A-inspired PP6F6 or Choke Capacitance Coupled SE2A3

Altec 414A

The Altec 414A has been my reference low frequency driver for more than two decades. As mentioned in this previous upload, I chose it over the 419A and 416A because it can play from ~ 30 Hz well into the upper midrange without cone breakup. That’s practically all of the fundamental notes found in a conductor's score. Hence, it only needs a bit of augmentation at the top end to fill in the last two octaves of musical notes and harmonics - exactly how I'm using it in my Altec 753C homage to the Western Electric monitor. 

IME, the only 12" driver that surpassed the Altec 414A's midrange performance was the Western Electric 728B, although the 414A is still ahead in terms of low frequency extension. Unfortunately, just like Western Electric drivers, Altec drivers in good condition have become harder to find. So let's check out a couple of alternatives...

Eminence DeltaLite 2512

I found this Eminence Delta Lite 2512 12" woofer at the Kutztown Radio Show for less than 10% of Parts Express' listed price. A quick Google search showed that it has a following among the spec-centric arena of audio professionals and hobbyists. Given its similar technical characteristics to the Altec 414A, I mounted it on an Altec 614-sized cabinet. 

Using music for critical testing, I didn't hear breakup modes in the vicinity of 1000-3000 Hz, just like the 414A. However, the midrange sounded dry and flat. Bass extension and heft is at par, if not better than, the Altec. But bass definition had a tendency to smear; hence, it was not quite as tuneful. I attribute the former and latter observations to the 2512's lack of musically consonant harmonic overtones. To fully appreciate the DeltaLite's abilities, one has to play it LOUD; otherwise, it sounds dynamically compressed and lacking in detail.

Pioneer PW-302A

I almost forgot that I had these vintage 12” Pioneer drivers until I found them in a box tucked in the garage. I actually have two pairs: one with bigger diameter dust caps (above) and the other with smaller dust caps (see video below). AFAICT, the voice coil size is identical on both and the build quality isn't quite as rugged as the Altec or the Eminence.

Initially installed in the smaller vented 614-style cabinet, I encountered similar issues to when I was testing the GE A1-400 and RCA 501S1. Given that the cone compliance of the PW-302A is similar to the latter two, I mounted it in the box I used with the GE and RCA.

Although not quite as extended in the low frequencies as the 2512 and 414A, the PW-302A's midrange was a lot richer in overtones than the Eminence. Whatever the Pioneer lacked in low-frequency energy was offset by its very tuneful rendition of bass lines. Just like the Altec, there's no need to crank up the volume to hear details and nuances. I only wish the Pioneer could equal the midrange snap of the Altec.

Listening to the PW-302A brought back fond memories of the time I discovered the Hamlin/Lafayette SK98/Pioneer PIM8/20. 

Tuned-pipe enclosure designed by Raymond H. Bates
More info: May 1955 issue of Audio Magazine (page 18)

I also mounted the Eminence and Pioneer in the above vintage DIY tuned-pipe corner cabinet, supplemented on top by an Emilar EH1210 horn + EC175 compression driver with an Intact Audio speaker-former + PIO caps in the high pass section.

If 90+ dB average SPLs and HiNRG low frequencies are top priorities in your listening agenda, this is the driver for you. 🍻

Hopefully, the remaining supply of Altec 414s and Pioneer PW-302As are conserved for music lovers who value subtlety and refinement at audio frequencies where music-making happens. 𝄞𝄢🎶🎻🎹