Anyone heard the new TC sounds drivers?

[paulspencer]

I had a look at their new site, and their new drivers look impressive!

http://www.tcsounds.com

In particular have a look at this:



One thing that looks appealing is they have worked on improving efficiency.

"With a Bl product of 45 Nm of torque over a relatively low impedance, the TC-5200's motor can displace an immense volume of air with relatively low current which translates into high sensitivity; however, the TC-5200 will require an amplifier that can provide a large enough voltage to compensate for the large back EMF produced from the coil."

They have an 18" driver with a sensitivity of 96 db and an fs of 20 Hz.

Another curious feature is that they have a VERY low Qts as they are designed for small sealed boxes. They also have a PR design, which is understandable since I'd expect it would be impossible to design a proper vented box for such a driver (try designing a small vented box which can tune around 20 Hz without turbulence when the driver is moving 3"!)

I'm curious to hear thoughts on how these would compare to Adire flat BL drivers.

Also I hear mention of split VC designs and multiple VC layers. What exactly are the functions of these features? If a driver has more than one VC layer, does this mean the density is increased to get a flat BL? Or could there be other reasons?

One downside I see is that it seems they have come up with an expensive implementation of technology, where Adire's technology doesn't appear to add any major cost in making the drivers.

[footstony]

Hi Paul,

Qes sounds nice for a bass horn. maybe Fs a bit low

Can you get them in Aus?

Regards Philip

[paulspencer]

Phillip, I haven't enquired, but I'd be surprised if you couldn't get them shipped here.

I hadn't thought of those drivers for a bass horn. I'm not sure exactly what makes a driver suitable, but I do know that my AV12s model better than anything else I've found for a sub bass horn to get down to 20 Hz.

How is the 42 Hz bass horn going?

[JoeM]

Yes they do ship here (melbourne). Fedex was $330 US for a 62pound 15" driver, cant remember which one now. I have decided to wait for the new LMS 4100neo or the LMS 5400 15". I wanted a tumult but found it utterly pathetic they dont have a dedicated website/forum for general discussion and getting hold of one is practicaly impossible.

If any aussies want to get a TC driver, shipping together would no doubt be cheaper.

btw, other than the xxls, any other decent subs available here?

[paulspencer]

Joe,

I only know of two main suppliers of decent sub drivers here - Aranmah acoustics (official Adire distributor in Mentone) and Wes Components.

Adire do have a forum - sound illusions:

http://www.carstereos.org/

If you do get that driver, I'd be very keen to hear about it.

Did you get a price on Tumult vs the TC?

[JoeM]

Paul,
Price from John at Aranmar acoustics from a 6 weeks ago:
Tumult
12", $845.00
15", $1150.00
All prices plus GST plus Freight
Problem is of course, he has none and says has been waiting on his shipment from adire for ages. He cant say when/if they will come or how many he gets..... For all I know it could be a year away.

As you know the LMS 5400 15" is $845 now and I *think* I read the LMS4100 would be about $1000 when it comes. Shipping will be some $350 odd USD for both. I could get the 15"LMS4000 for USD$600 now, but the savings made will go straight into a more powerfull QSC amp as it is quite insensitive.

12" XXLS from Wes components is AU$375. Would need 3 or 4 of these, but thats cool.

Your more than welcome to hear it when I get it set up. Im interested in your thoughts actually, what do you think is the best driver choice from the above with a priority to SQ for music. Im hoping to achieve extension to 20Hz in medium room crossing at 80Hz. Will go sealed, again for SQ.

Must admit, Im leaning toward several sealed xxls boxes. Availability and mobility is good but not sure if they will best the tumult or TC for extension and SPL.

[paulspencer]

Joe, I'd be very interested to hear what you end up with. I believe the XLS is a great driver, it has been around a long time and when it first came out, it was state of the art. Now subwoofer design has moved forward but it remains the same. I think there are better choices.

Take a look at the Rythmik audio direct servo kit for example. It deals with sources of distortion that are not addressed in even the very impressive Adire and TC sounds drivers. I wonder if it is actually better.

The Exodus audio CX series drivers available at Acoustic Visions are also worth considering - not pretty, but they have XBL2 and they are much cheaper than Tumult.

I don't know which would be better - TC sounds or Adire. They both appear are state of the art.

I think you could do well with any of these options.

I am in favour of dual driver options. This allows push pull for reduced distortion, as well as back to back mounting on opposite sides of the box which reduces vibration a lot.

Also consider some of the practicalities. Higher excursion drivers are very difficult if not impossible to get a vented box. Also, higher excursion means you need more power to get more output, hence higher thermal compression. It is harder to use more excursion. My drivers have 46mm p-p excursion, but I find the power required to use it is huge, and it ends up being more for headroom than for output. I'm starting to think that a number of not so extreme drivers is a sensible way to get SPL.

I use Behringer EP2500 as its an excellent value for money amp, and I see no reason to spend any more. It has up to 2.4kw of power and at around $800 it is a bargain. I have tried 450w second hand pro amps like Alesis and QSC and found their limits before my drivers ran out of steam, but the extra power in this amp is noticeable and I don't find it runs out of steam. It always seems to have enough steam to never run into clipping after a few years (only 2 exceptions ever), yet those other amps I ran them into clipping within a short demo period. Even now that I've put my subs into a smaller box, with a modified crossover with higher gain, demanding more of the amps, it still has no problems.

If I were you I'd also look at some simulations to see how the drivers you are interested in model. I know you mentioned sealed for SQ, but I'd consider trying a vented design. I have mine in a sealed prototype box which is temporary - I don't have much space. But when I make a more serious box when I move out, I'm thinking 20 Hz bass horn. If not for that, then I'd probably go for a vented box.

Perhaps at some stage we could organise a subwoofer meet up day, where we compare some subs. I have ultracurve and a microphone to calibrate them all flat for a fair comparison. Now if we could get an XLS, Rythmik servo, and a TC as well as my AV12s, that would be great.

[454Casull]

Torque? WTF?

[BAM]

A driver with a more powerful motor can take advantage of reflex loading in a smaller enclosure than a driver with a weaker motor. This may be what is being referred to as 'torque', though it is actually a 'force', not a torque. Technically speaking. But it's like torque in an engine.

[ScottG]

They look*ED* quite nice until I looked a little closer at eff..

1. The measurement is "Spl"??? This beg's any number of questions.

2. The thing has *****4***** VC's - this raises the question: how were the coils connected to achieve the "Spl" rating? Assuming Re is 4.8 Ohms per coil then the nominal impeadance is likely to be about 6 ohms (..maybe a tad more). Now, if they paralleled ALL 4 (to get their "Spl" rating), then you are looking at a nominal impeadance of 1.5 Ohms. Thats a pretty tough load for ANY amplifier.. then factor in the amount of back EMF the thing will produce.. ergggg.. most amps will choke with this combination (..which is likely why they have diagram at the bottom suggesting multiple amplifiers).

So my conclusion is.. (not surpising):

Take their "Spl" rating as pure marketing BS. Its likely another high mass low eff. sub (i.e. an H.T. "Thumper") *posing* as High Eff. design.