which DST or Seas driver(s) to put with 27TDFC..

[Andy_G]

I currently have some funds for a future project..
I have a pair of 27TDFC's and am trying to decide which of the DST or Seas mid/woofers, 6.5" or 8" to put with them.
Series x-o of course..;-))
medium bookshelf or maybe small MT tower.... purely for stereo music.

ideas, pics, etc of projects welcome !!

something out of the ordinary in visual design also welcome .. I'm dry of ideas at the moment, struggling :-(
ever hit the "brain full" stage???????? :-((((((
sorta like writer's block I guess! looking for a spark !!

also looking for design ideas for a TB 3" + 6.5 Audax woofer.

get those minds working, guys !!!!

Thanks, AG

[Pete Schumacher ®]

> I currently have some funds for a future
> project..
> I have a pair of 27TDFC's and am trying to
> decide which of the DST or Seas mid/woofers,
> 6.5" or 8" to put with them.
> Series x-o of course..;-))
> medium bookshelf or maybe small MT tower....
> purely for stereo music.

> ideas, pics, etc of projects welcome !!

> something out of the ordinary in visual
> design also welcome .. I'm dry of ideas at
> the moment, struggling :-(
> ever hit the "brain full"
> stage???????? :-((((((
> sorta like writer's block I guess! looking
> for a spark !!

> also looking for design ideas for a TB
> 3" + 6.5 Audax woofer.

> get those minds working, guys !!!!

> Thanks, AG

How about a 3-way?

830668 or 830669, 830873 as a mid and the 27TDFC on top?

Also, how about a two way or 2.5-way using the 830884 8" HDS Exclusive crossed at 1500Hz, LR4?

Then of course, you could always pair up that tweeter with the 830883 or 830875 7" drivers in a two way TM or MTM.

Peerless makes so many excellent drivers.

I'm really looking hard at doing a two way with their HDS tweeter and the 830884 crossed around 1.5KHz. Zaph's test showed a very low distortion tweeter that can handle a low crossover point.

[ipee]

Provided Link: Seas P17RC / 27TFFC


Andy, G-day mate,

I did a project (2-way sealed) using a Seas P17RC and a Seas 27TFFC (similar to your tweeter) and was impressed with the sound, as were the other attendees at the Florida DIY. You don't hear too much about this driver, but I recall reading a post by PJ that he liked them also. Crossover was done by Pierre Lorraine.

Specs
<A HREF="http://www.madisound.com/pdf/seas/h353.pdf">http://www.madisound.com/pdf/seas/h353.pdf</A>

[jyourison]

> I currently have some funds for a future
> project..
> I have a pair of 27TDFC's and am trying to
> decide which of the DST or Seas mid/woofers,
> 6.5" or 8" to put with them.
> Series x-o of course..;-))
> medium bookshelf or maybe small MT tower....
> purely for stereo music.

> ideas, pics, etc of projects welcome !!

> something out of the ordinary in visual
> design also welcome .. I'm dry of ideas at
> the moment, struggling :-(
> ever hit the "brain full"
> stage???????? :-((((((
> sorta like writer's block I guess! looking
> for a spark !!

> also looking for design ideas for a TB
> 3" + 6.5 Audax woofer.

> get those minds working, guys !!!!

> Thanks, AG

Pete's suggestions are great. And some of those look pretty cool. You could also consider the Vifa MG series from DST. They are detailed and yet smooth enough for series crossover use. The yellow cones would work well with black or any deep colored wood. Maybe a bumblebee theme? Paul Hilgeman may have used the MG22 with a Seas tweeter like that one. I've used the MG14 with excellent results, and the MG18 should do fine as well.

[JRT]

Provided Link: http://www.musicanddesign.com/HybridDesign.html


Maybe its time to play with an open baffle dipole?

I think you can get some good ideas from John Kreskovsky's Nao-mini for an inexpensive design.

The 2way panels use passive crossovers with some additional EQ applied upstream from the amp. You could very probably power the main panels with your modified Dynacos.

If you are put off by the thought of applying EQ ahead of your Dynacos, recall that LP playback requires RIAA filters and CD playback require digital reconstruction filters, so you are getting some of that already regardless.

I know you tend to dislike rectangles. You could start from scratch with your own design, or use John's if you preserve the critical baffle dimensions.

[romanbednarek]

Provided Link: RJB Audio - Galatea


> I currently have some funds for a future
> project..
> I have a pair of 27TDFC's and am trying to
> decide which of the DST or Seas mid/woofers,
> 6.5" or 8" to put with them.
> Series x-o of course..;-))
> medium bookshelf or maybe small MT tower....
> purely for stereo music.

> ideas, pics, etc of projects welcome !!

> something out of the ordinary in visual
> design also welcome .. I'm dry of ideas at
> the moment, struggling :-(
> ever hit the "brain full"
> stage???????? :-((((((
> sorta like writer's block I guess! looking
> for a spark !!

> also looking for design ideas for a TB
> 3" + 6.5 Audax woofer.

> get those minds working, guys !!!!

> Thanks, AG

I've used that tweeter in several designs. My Calypso design uses the Seas CA15RLY with a 2nd order parallel crossover and the bass is surprisingly deep for that small driver.

The design at the link below (shown below) uses the Seas CB17RCY/P driver. The published design uses a 4th order parallel filter but I also built a 2nd order version and one with an AR series crossover. There are a few comments on the series version and I have the crossover design somewhere on my computer. The AR series version only uses 4 components but I found it to be a bit on the warm side with no way to compensate due to the low parts count and the fact that all of the parts interact with each other (my main gripe against series crossovers is the decreased flexibility when it comes to tuning). If you are interested in this project I can see if I can find the crossover schematic for the AR series version. The CB17 driver has a pretty high sensitivity but the bass isn't super deep (upper 40's f3).

If you don't already know I'm a big fan of paper drivers in the midrange region as you can see in my choices above. Although I haven't used them before I think some of the new Peerless drivers have a lot of potential like the HDS Exclusive series (like the ones John k... uses in his Nao Mini design). Peerless has some other versions that are a bit smoother that may work better with a series crossover.

The 27TDFC is definitely a winner in my book and should work extremely well with a series crossover. Good luck with your driver hunting and let me know if you have any questions.

[JRT]

> also looking for design ideas for a TB
> 3" + 6.5 Audax woofer.

How about using those in a pair of nearfield desktop loudspeakers?

The high frequency directionality of the 3" TBs makes for a small sweet spot, which is what you get sitting in front of a monitor.

One of the bigger problems in loudspeakers used in that application is interference from all of the reflections.

The 6.5" Audax could be crossed high enough that the 3" TBs could be placed on an open baffle dipole alignment. That would put a lot of the problematic reflective surfaces in the dipole null.

The Audax midwoofers would have to be used in enclosed or stuffed/leaky alignments to get the needed extension. The nearby boundary reflections would be less of a problem for those with the triple digit low pass frequency of the midwoofers' passband.

Create a small flat baffle with some sort of quasi-triangular shape, with some curve to it, maybe something more like a Wankel rotor or a StarTrek insignia.

Use some PVC pipe to enclose the rear of each Audax.

Use passive crossovers and place some active EQ upstream of the amplifier to reduce the drive requirements of the amplifier (as compared to putting all of the dipole EQ in the passive crossover).

[billcurrier]

> Andy, G-day mate,

> I did a project (2-way sealed) using a Seas
> P17RC and a Seas 27TFFC (similar to your
> tweeter) and was impressed with the sound,
> as were the other attendees at the Florida
> DIY. You don't hear too much about this
> driver, but I recall reading a post by PJ
> that he liked them also. Crossover was done
> by Pierre Lorraine.

> Specs
> <A HREF="http://www.madisound.com/pdf/seas/h353.pdf">http://www.madisound.com/pdf/seas/h353.pdf</A>

Robert,

Thanks for posting that design. I really like the P17RC's and Pierre does beautiful crossover work. I have a pair of P17RC's laying around and may need to purchase the 27TFFC's. Great to have all the cabinet details.

Bill