What would you want from a dedicated HT line?

**Fi Audio** · **02-10-09, 10:14 PM**

Just a little feeler to see what people might be interested in seeing from a Fi "HT" line. We are trying to keep it realistic, although we can do just about anything that physics allows for.

Thanks,
Scott

**Ricci** · **02-11-09, 04:05 PM**

Oh goody... I get to post first.

These are the properties that I'd like to see on a line of HT drivers. I'm one of the people who is willing to pay a bit for some extra quality so budgetary concerns aren't really on my radar.

High displacement for the low bass in soundtracks and low distortion, with high SQ and good upper end bass extension for blending with the mains. Versatility so that they can be used in resonant and sealed designs, with an emphasis on small sealed box requirements. 30mm or more one way would be great and the more the better. It doesn't need to be as crazy as a XXX, but massive displacement headroom and clearances like that is a plus. Keep it linear and low distortion too. I'd like to see a linear motor system used (split coil maybe/ counter coil?) to that end. Quiet high excursion operation. Also low and well controlled inductance through whatever means necessary(shorting rings/ counter coil, whatever). Solid venting and cooling with high thermal power handling. High BL to keep the efficiency up and the box sizes reasonable. I know that using a linear motor automatically hurts you there but it can be done. I'd like to see it have a neo based motor too. Finally, keep it plain and classy looking. Offer it all the way up to a 21 or 22" like the one we already discussed.

That'll only be what? About $1500 per driver?

Abbreviated version...

1. Extreme linearity/High displacement
2. High BL
3. Well controlled inductance
4. High thermal power handling/venting/cooling
5. Low self noise at high excursion
6. Rugged
7. Reasonable box size requirements
8. Versatile
9. Classy looking

Perhaps you could do 60% of that in a more budget oriented line?

**Mike P.** · **02-11-09, 04:28 PM**

Quote:

Oh goody... I get to post first.

And I KNEW you would be!

**robseyes** · **02-11-09, 07:39 PM**

Quote:

Ricci wrote:

Oh goody... I get to post first.

These are the properties that I'd like to see on a line of HT drivers. I'm one of the people who is willing to pay a bit for some extra quality so budgetary concerns aren't really on my radar.

High displacement for the low bass in soundtracks and low distortion, with high SQ and good upper end bass extension for blending with the mains. Versatility so that they can be used in resonant and sealed designs, with an emphasis on small sealed box requirements. 30mm or more one way would be great and the more the better. It doesn't need to be as crazy as a XXX, but massive displacement headroom and clearances like that is a plus. Keep it linear and low distortion too. I'd like to see a linear motor system used (split coil maybe/ counter coil?) to that end. Quiet high excursion operation. Also low and well controlled inductance through whatever means necessary(shorting rings/ counter coil, whatever). Solid venting and cooling with high thermal power handling. High BL to keep the efficiency up and the box sizes reasonable. I know that using a linear motor automatically hurts you there but it can be done. I'd like to see it have a neo based motor too. Finally, keep it plain and classy looking. Offer it all the way up to a 21 or 22" like the one we already discussed.

That'll only be what? About $1500 per driver?

Abbreviated version...

1. Extreme linearity/High displacement
2. High BL
3. Well controlled inductance
4. High thermal power handling/venting/cooling
5. Low self noise at high excursion
6. Rugged
7. Reasonable box size requirements
8. Versatile
9. Classy looking

Perhaps you could do 60% of that in a more budget oriented line?

I agree whole heartily! Perhaps something similar to the original Avalanche series with a little more BL (especially for the 18), at least 30 mm of Xmax, better upper bass response (lower inductance),all for a somewhat reasonable price point ($275-$350).Not sure if that is reasonable

, but it sure would be cool.

**Sonnie** · **02-11-09, 08:48 PM**

Sounds like you guys want an LMS-5400 on the cheap!

**Ricci** · **02-12-09, 12:11 AM**

I want better than an LMS for whatever it cost it takes to make that happen.

If something with 70% of that performance can be done at a decent cost that'd be cool too.

**Fi Audio** · **02-20-09, 02:29 AM**

I actually had a chance to do some FEA for this last night and came up with a nice little solution (havent had a chance in long time to do FEA for fun...) I definitely think we can meet those goals at a reasonable price point. Only sticking point is the baskets... but I do have a solution for that as well with some plate and one of the CNCs

Need to check on a patent as I have a feeling that there might be something covered on how I want to do things already. If not, Ill see about getting one going.

**Ricci** · **02-20-09, 01:03 PM**

Do it Scott! I'll buy them...and so will others... patents schmatents... they'll never know on something with this kind of volume if you don't advertise exactly what is going on in that part of the design.

. .Maybe...

**Fi Audio** · **02-20-09, 03:13 PM**

Lol... I definitely dont work that way. I give credit where it is due, or figure another solution. I had heard mention that there was a patent on the Alumapro M16 style basket for its construction. I havent found anything, but will absolutely exhaust my search ability and that of my patent attorneys before I sell a single thing. While my design is no where near the same as theirs, I do need to see what the patent covers should there actually be one.

**robseyes** · **02-20-09, 05:18 PM**

Quote:

Fi Audio wrote:

I actually had a chance to do some FEA for this last night and came up with a nice little solution (havent had a chance in long time to do FEA for fun...) I definitely think we can meet those goals at a reasonable price point. Only sticking point is the baskets... but I do have a solution for that as well with some plate and one of the CNCs

Need to check on a patent as I have a feeling that there might be something covered on how I want to do things already. If not, Ill see about getting one going.

What were you thinking? A driver that could out-do an LMS or a more economical series that has 30+ mm of x-max & lower inductance?.........Is it too much to ask for a little efiiciency too?

(i know i know there are tradeoffs in all designs)

**Ricci** · **02-21-09, 10:32 AM**

Scott,
I was kidding about the patent thing. I'll have to look up that Alumapro design...

Robseyes,

Getting decent efficiency (low mms, High BL), really long linear throw and low inductance all in one is the ticket...usually tricky and expensive to do. Some of these fight against each other.

**NDMstang65** · **02-22-09, 02:05 PM**

Shouldn't be an issue

**robseyes** · **02-23-09, 08:42 PM**

Quote:

Ricci wrote:

Robseyes,

Getting decent efficiency (low mms, High BL), really long linear throw and low inductance all in one is the ticket...usually tricky and expensive to do. Some of these fight against each other.

I know, I know, but he did ask you know!

By the way, I don't post very often, but I really have enjoyed reading about your Re xxx build. Very well designed & nicely implemented. I can't wait to hear your impressions of multiple sealed with those monsters.

Hopefully a few pics too!

Bob

**Ricci** · **02-24-09, 04:21 PM**

I'm still really proud of that subwoofer. I'm kind of stalled out on wrapping up the sealed XXX's. I was going to go IB with them

, but I decided that my place doesn't really lend itself to that. I'll get to it eventually. Busy, Busy.

**Ricci** · **02-24-09, 04:26 PM**

Quote:

Fi Audio wrote:

Lol... I definitely dont work that way. I give credit where it is due, or figure another solution. I had heard mention that there was a patent on the Alumapro M16 style basket for its construction. I havent found anything, but will absolutely exhaust my search ability and that of my patent attorneys before I sell a single thing. While my design is no where near the same as theirs, I do need to see what the patent covers should there actually be one.

I checked out that M16 driver and it looks pretty nice. I can't believe I've never even heard of that one. Looks like it's either DD or split coil, field serviceable, machined frame and all of that. I really couldn't find too much info on it. Just a few pictures. Woofersetc show it in stock though. I don't see how they could patent that basket construction method really. It's a nice frame but it's not like it's an invention or anything. It's just a machined frame instead of the usual methods. You obviously wouldn't copy it just build yours the same way.

**Fi Audio** · **02-25-09, 04:00 PM**

Patents are funny things... there seems to be a cycle with the US Patent office on what they will and wont patent. Right now seems to be a better time to patent things as they are a little freer with them. A few years back denials were almost a given (mostly due to the lack of comprehension of what as trying to be patented).

Im always wary about other peoples IP. I have yet to find anything, and our design is definitely different... but I did want to see theirs, if there was one, first.

Might need to pull some fixtures off of one of the machines and make some chips

**robseyes** · **02-26-09, 01:23 PM**

Could you do a tall rubber surround similar to the one TC uses? Or do they have that under patent? It seems like it works pretty well & just flat out looks cool!

**NDMstang65** · **02-26-09, 01:31 PM**

No..

Those surrounds have issues, granted it may look cool...but puckering/folding/collapsing is something that we will not get into with a high roll surround like that.

We're more of a bang for the buck type company keeping you guys in mind the entire time, if it is not going to add performance and just add cost, we're not going to do it

.

Cheers!
Nick

**Fi Audio** · **02-27-09, 01:25 AM**

I have played with FEA/Mechanical design of the taller profile surrounds for some time and have not found a profile and material combination that Im really happy with (yet). And while it appears that they might have something patent pending, there are an infinite array of profiles that could be done as well. Just a matter of finding a good "durable" combination of profile and materials. While I have ran across as well as designed a surround that worked well, it didnt last over 10 million cycles before developing modal stress points and visible wear. Granted this is at higher excursion, but isnt that the point?

We will keep playing with things when time permits.

**ngsm13** · **02-27-09, 10:25 AM**

I see you mentioned HT Line, so are you looking at the possibility of multiple offerings Scott?

If so, it would be nice to see a mid-lower price point! Perform well with great output with modest input power.

nG

**onebadmonte** · **02-27-09, 03:41 PM**

What about a good mid/full range speaker?

**NDMstang65** · **02-27-09, 04:22 PM**

We're just in infancy as far as talks of an entire line...but we'll see where the road takes us.

Hugo, That can definitely be done, ideally what would you be looking for?

**onebadmonte** · **02-27-09, 05:11 PM**

Lately I've been checking out the rear loaded horns on the frugal horn site. Most of their designs use fostex speakers. Maybe a driver along the lines of a fostex. One with a weezer cone would be cool, nostalgic sort of.

I'm not a connoisseur by any means, I'm just digging the looks of a horn enclosure right now. I know its not for everyone. Thank for the chance to give some input. Fi makes great subs, I figure you guys could do wonders with the rest of the frequency range.

**NDMstang65** · **02-27-09, 06:00 PM**

With our new measurement system that we've came up with the higher frequency stuff isn't going to be an issue. We'll see what happens as time progresses..

Any other input from others? I'm all ears.

**Fi Audio** · **02-27-09, 10:38 PM**

I have always been a fan of wide range drivers... truly there isnt a full range driver within any sort of realistic use out there. My computer speakers are wide range horn loaded 3" drivers with a bottom cut off of 55 Hz. I have designed several wide band drivers and if things ever settle down and I get free time to play in the lab Id love to turn the laser scanning vibrometer on a full range driver. It would give me a huge advantage over how I designed and tweaked the older drivers.

But... In all honesty Fi will probably stay a sub only company. Im not opposed to another company that caters to some more esoteric drivers, but I really dont think it is in line with what Fi is about.

Advertisement