- Written by Jim Milton
- Published on 12 November 2012
Design and Setup of the Newform Research Ribbon Tower Speakers
I stumbled across the Newform website about 3 years ago when I was in the mood for researching ribbon drivers. I invariably came across Martin Logan and Magnepan, the two most popular companies that use ribbons and diaphragms. Newform popped up as well and caught my eye with their unique and distinctive designs. I have never been able to audition Logans or Maggies because my room is too confined to work with the back wall reflection that makes those panels work their magic. Usually you would need to move them 3 feet or more out into the listening area and in an 11 X 10 room, and that just isn’t an option.
The Newforms have a unique ribbon tweeter that has a narrow (3/4”), tightly suspended diaphragms that provide extremely good horizontal dispersion and no back wall reflection. That back wall reflection can smear the imaging by allowing the initial sound wave to be muddied by the slightly delayed back wall reflection. The narrower tweeter design also works like a line source so the sound has excellent horizontal dispersion with minimal side wall interaction.
Their website provides this explanation: “Our ribbons have the smallest acoustic profile of any driver operating from 1 kHz up. When it comes to acoustic profile, the less you see, the more you hear. The entire structure is only 3 1/4” wide and 2 1/2” deep. It is heavily beveled at the front and the diaphragm is within 1/8” of the front of the structure. Given the narrow width of the diaphragm (dispersion is a function of diaphragm width and wavelength), there is very little to interfere with extremely even off-axis response. A critical consideration in producing a truly coherent sound field in home theater.” The entire surface of the ribbon vibrates as a whole unit, as opposed to, say a dome, which has different radiation characteristic across the entire curved surface. Domes are prone to “hot spotting”, break up and are often supplemented with an acoustic lens to help increase their dispersion pattern. These problems are usually circumvented with a ribbon driver.
When the Towers arrived at my house, I was somewhat surprised that they came in four boxes. These are the first speakers that I have had to assemble the bases, tweeters and crossovers. Though it looked a bit intimidating, it was very easy to assemble parts (even without any instructions). Mind you, the Towers I am reviewing are a “pre-production” model, which means aesthetically they may undergo some small changes, but sonically they are ready for prime time. My samples came with a “natural” finish, which actually looked quite nice in satiny honey-gold. The ribbons weigh in at about approximately 20 pounds each and I was impressed with the heft and finish of their construction.
At their bottom ends were the wiring needed to connect them to the binding posts on the tower cabinets (again, color coded for correct phasing).
The cabinets are a sealed design and have 6 mid bass drivers in each tower. Being sealed may give up a bit a deep extension, but the overall bass output will be more accurate and tight. On the bottom of each cabinet was a layer of felt, so when they get attached to their bases, they fit together tightly without scratching the finish.
The external crossovers are clearly labeled as are the terminals on the cabinets, so hooking up everything was a breeze. A wrench and interconnects were included, so my total setup time, sans instructions, was less than 20 minutes.
With assembly complete, the first thought that crossed my mind was that the elongated tweeter looks to be blocking half of the mid bass drivers and I wondered how that might affect the overall sound of the speakers.
Setting up the speakers in my listening room was fairly straight forward. Because these speakers have a relatively small footprint, they were easy to position for optimum toeing in or out.
I placed the crossovers behind the speakers on the back where the base overhangs with the wires that connected to the terminals being just the right length for connecting to the binding posts.
Why an external crossover system, you might ask? From their website, they offer “upgradability” to other types of crossover components and having the crossovers within easy reach allows you to make these upgrades without cracking open the cabinets or pulling out driver to access the inside. This seems to me to be a very practical, if not logical, design choice.
I placed the speakers about eight feet apart at equidistance from my seat, originally facing me directly and ultimately found the sweet spot with them slightly toed out. When I first fired up the speakers, I was standing next to them, having just pressed the “play” button on my Oppo. I thought I had made a mistake in the wiring of the tweeters, because the sound was very dull. This was when I learned that the vertical dispersion of a line source ribbon is poor. However, when I sat down and had the tweeters at ear level, well, this is when I learned that a line source ribbon has wonderful horizontal dispersion. I can’t stress enough about positioning the tweeters so that they hit your ears fully when you are in your listen spot on the couch. What a difference a few inches in height can make! Unlike a radiating diaphragm (i.e. Maggies), the Newforms do not radiate their energy toward the rear wall, but completely forward, toward the listener.
Because the back side of the tweeter was convexed in shape, I did not find the location in front of the mid bass drivers to adversely affect the sound at all. Because of the number of mids (12 in all!), the overall sound and depth of the bass was actually quite good. I was able to get down to 40-38Hz without the use of a sub. Newform recommends pairing these with a sub for best performance, but depending on your musical tastes, I could see (hear) forgoing a sub altogether with these for about 95% of the music you love. The only negative I had, sound wise, was when pushed the Towers to really high volume levels, the upper mid bass region started to sound congested with complex orchestral music. That all but disappeared when I coupled them with a sub with a crossover at around 80-75Hz. With the sub engaged, I could listen to everything from string quartets (these ribbons love to reproduce strings) to Roxy Music at moderately high volume and everything sounded open and clear. In order to “point” the tweeters to my ears, I had to place some blocks under the front of the bases to tilt them up a bit. It would have been nice if adjustable feet were included with the bases. It would be even cooler if there was an adjustable slide to raise the tweeters higher or lower by a few inches…but hey, that’s just me. (I spoke with John Meyers from Newform about this and he sent me a picture of their dual ribbon tower with this adjustable slide in place. Like me, these guys are geniuses!)
The towers can be custom ordered with a second set of tweeters, but another set lower than the first would not provide much benefit, I would think. I noticed a lower sensitivity when compared to my Revel F12s. I had to pump the volume level up a bit and noticed that my 200 watt monoblocks were running slightly warm. Normally, they run cool to the touch after heavy usage. I would recommend running the Towers with at least 100 watts of good amplification and NOT a small tube amplifier, in order to get the best sound out of them.