Peerless 5 - A 2.5 way - MTMMM

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Peerless MTMMM and MMTMMMM - 2.5 way designs

Feedback sought. A 2.5 way.

Goal is to see what i could do with relatively cheap drivers and to get system sensitivity >= 91 dB. Limited my tweeter choices (as you can see - no padding).

Minimum impedance 4.6 ohms @ 3,600 Hz.

Given the flange of the woofer, you could get away with surface mounting these so no need for a router if you can't do recessed holes.

LR4 acoustic target. Crossover point high (~2,600Hz), but in order to protect the tweeter. Went as steep as I could without going fancy.

Drivers:
Woofer - Peerless BC18EK05-08 6.5"
Peerless BC18WK05-08 6.5" Paper Cone Woofer

Tweeter - Peerless DX25TG59-04 1"
Vifa DX25TG59-04 1" Fabric Dome Tweeter
 

Attachments

  • Crossover.png
    Crossover.png
    23.3 KB · Views: 618
  • System Impedance.png
    System Impedance.png
    41 KB · Views: 617
  • Network transfer function.png
    Network transfer function.png
    38.5 KB · Views: 573
  • System frequency response.png
    System frequency response.png
    78 KB · Views: 589
  • Reverse null.png
    Reverse null.png
    36.8 KB · Views: 612
Last edited:
Hi Dave. Just go back to posts around 2011 in the Elsinore thread and you will see version 5 with Peerless mid woofers. The tweeter remains unchanged. Version 6 has the SB mid woofers which are not so much an upgrade as an alternative. I have the V5's and a friend of mine has the V6's and neither of us can really point to any discernable differences. We are both driving them with a pair of Monarchy SM70 pro class A monoblocks and are extremely happy with both the speakers and the amps. A very good combination as the Elsinore's are very efficient.



When I saw your first post I thought "That looks familiar"
 
The original Elsinores MK1 used the poly cone Peerless midwoofers and some time later (can't remember which version) went to the 830875 which has a Nomex cone and is slightly more efficient. The 810921 (Peerless) or D2608 (Scanspeak) Tweeters are identical. There is quite a story why two manufacturers made an identical unit. The D2608 and the 810921 are both listed as available from WES components in NSW.
 
Hi Dave,

Building a "clone" of the Elsinore speakers with the cheaper paper cone 830657 could be an interresting project. The four 6.5" could be paired with the Vifa DX25TG59 as seen in this project :

Tarkus - undefinition

FIY I've build the Nomex 164, a 2.5 way from Troels Gravesenand after the Elsinore and I didn't found the second one more sensitive neither best sounding also.
 
Hi Dave,

Building a "clone" of the Elsinore speakers with the cheaper paper cone 830657 could be an interresting project. The four 6.5" could be paired with the Vifa DX25TG59 as seen in this project :

Tarkus - undefinition

FIY I've build the Nomex 164, a 2.5 way from Troels Gravesenand after the Elsinore and I didn't found the second one more sensitive neither best sounding also.

Cheers. I actually swapped the BC18 for the 830657 and paired it with the DX25 before I found Paul's project above (The Tarkus). I'm just redoing the crossover with these. I need to model excursion because 3.64mm xmax doesn't give you a lot to play with.
 
Member
Joined 2004
Paid Member
Cheap/decent tweeters?

Peerless XT25BG60-04 Vifa Ring Dome Tweeter. Another few dollars at $28 each, with 91.5dB/1W and fairly well-regarded.
Vifa XT25BG60-04 Vifa Ring Dome Tweeter - Double Magnet - 4 ohm

How about Peerless DQ25SC16-04, 1" Titanium Dome Tweeter at $23? It's 94dB/2.83V:
Vifa DQ25SC16-04, 1" Titanium Dome Tweeter

Planar tweeter? Hi-Vi RT1C-A Isodynamic Tweeter, 120mm, 94dB at $38. Xo too high perhaps?
Hi-Vi RT1C-A Isodynamic Tweeter, 120mm, 94dB

It's worth paying more than half the driver budget for the tweeter alone...
 
Cheap/decent tweeters?

Peerless XT25BG60-04 Vifa Ring Dome Tweeter. Another few dollars at $28 each, with 91.5dB/1W and fairly well-regarded.
Vifa XT25BG60-04 Vifa Ring Dome Tweeter - Double Magnet - 4 ohm

How about Peerless DQ25SC16-04, 1" Titanium Dome Tweeter at $23? It's 94dB/2.83V:
Vifa DQ25SC16-04, 1" Titanium Dome Tweeter

Planar tweeter? Hi-Vi RT1C-A Isodynamic Tweeter, 120mm, 94dB at $38. Xo too high perhaps?
Hi-Vi RT1C-A Isodynamic Tweeter, 120mm, 94dB

It's worth paying more than half the driver budget for the tweeter alone...

The Hi-vi has too higher a xo point (4500) given the beaming issues I'll have with 6.5" drivers.

The XT25 has better odd order harmonics > 2Khz but doesn't quite have the smooth on-axis response of the DX and better bottom end extension for shaping the tail.

the DQ25 has a higher Fs (1320Hz) and I personally (for no other reason than a rule of thumb) prefer to xo at >= 2* the FS of the driver. don't know where I got that rule of thumb from (whether material to distortion or allowing an impedance correction circuit to be avoided). In anycase I don't have a distortion plot to know if any better than the DX25.

Thanks for the suggestions though!
 
Member
Joined 2004
Paid Member
Zaph said nice things about distortion in DQ25, but that was 15 years ago. I like its smaller face for close MTM spacing and built-in dome shield.
2x Fs is a good place to start, but you can easily bend a rule of thumb.

It would be nice if there was an 8 Ohm tweeter out there to keep the Z curve flatter out there.
 
Zaph said nice things about distortion in DQ25, but that was 15 years ago. I like its smaller face for close MTM spacing and built-in dome shield.
2x Fs is a good place to start, but you can easily bend a rule of thumb.

It would be nice if there was an 8 Ohm tweeter out there to keep the Z curve flatter out there.

Agreed on the 4 ohm challenge. Latest modeling attempts are not looking Z healthy at higher frequency (3 Ohm dips). Stay tuned....
 
I've come up with 2 designs, both using the Peerless 830657 woofer and Vifa DX25TG05-04 (aka Scan speak D2604-830000).

Design "A" - a 4 woofer MTMMM 2.5 way. Min impedance 3.6 ohms between 4KHz and 7Khz
Design "B" - a 6 woofer MMTMMMM 2.5 way. Min impedance 3.0 ohms at 9KHz

Enclosures
A - 80L vented, tuned to 40 Hz, F3 = 54Hz, Max SPL 111dB. System sensitivity ~ 89 dB (including ~ 4 dB baffle step compensation)
B - 120L vented, tuned to 40 Hz, F3 = 54Hz, Max SPL 114dB. System sensitivity ~ 92 dB (including ~ 4 dB baffle step compensation)

The remainder of the images in this post relate to the A design
 

Attachments

  • Design A - NTF.png
    Design A - NTF.png
    45.5 KB · Views: 73
  • Design A - Impedance.png
    Design A - Impedance.png
    39.3 KB · Views: 58
  • Design A - FR.png
    Design A - FR.png
    92.8 KB · Views: 186
  • Design A - crossover.png
    Design A - crossover.png
    18.8 KB · Views: 189
  • Design A - baffle.png
    Design A - baffle.png
    202.7 KB · Views: 254
Hi Dave,

I vote for the A design MTMMM - 80L vented, tuned to 40 Hz, F3 = 54Hz, Max SPL 111dB. System sensitivity ~ 89 dB (including ~ 4 dB baffle step compensation)

They are already very big speakers !

IMHO if you want more sensitivity go for more sensitive drivers not for more drivers.
 
Last edited:
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.