[Endo2112]

It would be an understatement to say those Pino's were outstanding!! Some of the best wines i've ever had, period!! and I have friends in the industry.

Don

[david45]

FYI


https://audioxpress.com/news/radian-audio-lm10-introduces-wide-band-planar-ribbon-transducer-at-ces-2023

[Hobbsmeerkat]

That's definitely a serious contender to replace the BG10 in a future revision. I've linked to them prior. Radian is also updating their other drivers for better performance as well, and the new LT6 seems to be a promising as a replacement for each pair of Neo 3s.

They measure better than the GRS versions from what we've seen, and don't have the same power limitations either.

But we don't have any immediate plans to design a new model around them.

[Endo2112]

Show the measurements??

Don

[Hobbsmeerkat]

There was some measurements on the product datasheet, but I don't see the download for them, at least not on my phone.

https://radianaudio.com/products/lm10n-wide-band-planar-ribbon-transducer

We haven't gotten one in for testing in house, but they look promising from what we've seen so far.

Edit: I think Radian is still in the process of updating their product pages but I found the original PDF elsewhere:

https://cdn.shopify.com/s/files/1/0111/0324/0254/files/LM10n-datasheet-v2.pdf?v=1666125534

[Hobbsmeerkat]

If we do the Radian LM10 we're either going stick to the 6mids or use 8 of them for taller version similar to the NX-Treme/LS9 in height.
And well likely use 8 or 9 LT6s in the standard, and 12 in the taller version.

Heres a rough idea of the design well be shooting for with the standard height version:




The drivers will likely be rear-mounted into a thick baffle to give the drivers a litte bit of a waveguide and stiffen the cabinet.

If we go either route, we will need to have custom LM10& LT6s made in order to match the impedance, & output and send some samples off to Jay & Don to allow them design the cabinet for the new drivers.

We're still spitballing the ideas, so any suggestions are currently welcome.

[Jaytor]

The current Line Force is a nice height aesthetically and does well in a room with average height ceilings. My listening room as 7'9" ceilings and they don't feel overwhelming. I think a taller version would be too much without being in a room with taller ceilings.

That said, there is a distinct difference in the way they sound when standing vs sitting. They don't sound bad when standing, but are clearly better when sitting. So for folks that want a speaker that still sounds outstanding for parties, etc., a taller version might be a bit better.

But I'm very happy with the size of mine and would pick them over a taller version if I had a choice.

[wgraft5]

I like that you are at least "spitballing" this. For me the standard height would work.

Wayne in Oregon

[david45]

Hobbs,

Why are custom drivers needed if you don’t mind me asking?

LT2 or 6LT? What’s a better match with the LT10? 3500hz crossover point?

[Hobbsmeerkat]

Hobbs,

Why are custom drivers needed if you don’t mind me asking?

LT2 or 6LT? What’s a better match with the LT10? 3500hz crossover point?

To better match impedance and output levels between the drivers.

For something like the old Super Mini, the better option would be the LT2 or LT3. The LT6 would be too tall for that application.
Ideally we like to crossover drivers as low as possible, typically 1500-2000Hz whenever possible. It allows for a more consistent off-axis response.

The LT6 is essentially two LT3s in a single chassis, so we can get away with using less drivers for similar output, which is ideal for a line-source design.

[david45]

To better match impedance and output levels between the drivers.

For something like the old Super Mini, the better option would be the LT2 or LT3. The LT6 would be too tall for that application.
Ideally we like to crossover drivers as low as possible, typically 1500-2000Hz whenever possible. It allows for a more consistent off-axis response.

The LT6 is essentially two LT3s in a single chassis, so we can get away with using less drivers for similar output, which is ideal for a line-source design.

LT6 doesn’t seem to have very good off-axis response compared to LT3 when looking at the charts. Also the new LT10 driver can keep its composure all the way to 4000Hz which was not possible with the old BG Neo10. In any case, it seems possible to cross it over considerably higher without hurting the heart of the midrange 🤷‍♂️

Thanks for answering my questions.

[Low distortion]

Yes the Radian 10 has amazing off axis dispersion up till 4K. Which wasn’t the case for the obsolete neo10. Which completely makes the case for crossing over below 3000hz only a pursuit to drastically increase distort in the tweeter.

[Jaytor]

Keep in mind that the two driver arrays have to sit side by side, so raising the crossover frequency will also result in more interference peaks and dips as the listener moves side to side.

[Low distortion]

Keep in mind that the two driver arrays have to sit side by side, so raising the crossover frequency will also result in more interference peaks and dips as the listener moves side to side.

The same layout compromise exists for both drivers in this design. Regardless of where the crossover frequency is set. The new LT10 is amazing off axis up till 4K. And the lower you cross the tweeter over, the lower the power handling, maximum SPL, and higher the distortion. The old Neo10 was garbage above 1500k. Which is why it was better suited for the lower crossover point. Which still means much higher tweeter distortion. The higher distortion was a design compromise needed with the obsolete Neo10. But thankfully the designer of both drivers, Igor, learned a few things over the years, and his latest drivers no longer need to deal with this compromise.

[Hobbsmeerkat]

Yes the Radian 10 has amazing off axis dispersion up till 4K. Which wasn’t the case for the obsolete neo10. Which completely makes the case for crossing over below 3000hz only a pursuit to drastically increase distort in the tweeter.

Distortion would only really be an issue with a single tweeter at high output. With many drivers wired in series-parallel groupings, each tweeter one is only moving a fraction of the distance a single tweeter would at the same output, greatly reducing distortion even at high output levels.

As mentioned above, a crossover at 3000-4000Hz would lead to a very narrow listening window. The lower the crossover point, the better the off-axis response and the wider the sweet spot.
and using the LT6 in an open-backed configuration will also unload the diaphragm, allowing it to play lower than the stock measurements allow.

[Low distortion]

As mentioned above, a crossover at 3000-4000Hz would lead to a very narrow listening window. The lower the crossover point, the better the off-axis response and the wider the sweet spot.

That might be the case for some drivers. But it isn’t the case for the LT10 until 4K. The off axis is actually better between 2-4K than it is at 1000-1500hz. 

[Danny Richie]

Distortion with these drivers are a non-issue. They have little to no rise at Fs and handle tons of power while still maintaining a linear response.

We use our single GR Neo 3 crossed down in the 1,400 to 1,500Hz range, with a little help from a wave guide, with no issues.

Running a line of these tweeters, including the new Radian models, completely takes distortion out of consideration. They can be crossed as low as 800 or 900Hz in many cases. Even at 100db each driver will see less than 1 watt each.

Another important factor to consider is acoustic center spacing. This is going to be about 4.5" apart in a horizontal plane. That is a wavelength of about 3kHz. So the crossover point has to be (by rule of thumb) below 3kHz to avoid any significant comb filtering in the horizontal plane. With a crossover near 1kHz (piece of cake) then you can move horizontally in either direction without the change in time arrival having any real effect on the response.

If the crossover were pushed up into the 4khz region then any movement left or right would create enough of a phase rotation to start causing some comb filtering. So anything beyond 20 degrees or so would result is significant holes in the response to the tune of up to 15db.

So the lower crossover points are a MUST.

[Hobbsmeerkat]

No, the drivers will stay in phase over a larger window the lower the crossover point is, and the further off-axis you have to move before the drivers begin to cancel out.
It's not just the LM10/Neo10 you have to be concerned with, it's really the crossover relation to the line of mids to the line of tweeters and mids that matters here.

[Low distortion]

A unique solution to the comb filtering issue would be to mount LT2 tweeters in the center of each LT10 with a special bracket, and time align them with DSP. This way the acoustic centres would be 0” apart. The baffle could be much skinnier as well.

[Low distortion]

The planar coaxial. Looks like someone thought of that already:

https://www.bmsspeakers.com/index.php-90.html?id=bms_4508nd

https://radianaudio.com/collections/coaxial-ribbon/products/6crn38lt6-line-array-driver