Next up in the shop: a LOUD, paper-cone 3 way

[Paul Carmody]

People often talk of doing brain-bashing "monkey coffin" designs. Those are cool; but I'd like to give the idea a bit more class in the looks department, and also a crossover that walks the line between high-resolution and kick-*** ;)

So here's the overall shape:

The drivers will be:
Peerless 830668 10" woofer
Peerless 830657 6.5" midwoofer
Vifa DX25 tweeter

The objective here is a high-quality speaker (on a bit of a budget) with a "classic paper sound," that can really dish out the SPL if asked to. I have very high hopes for the Peerless 10," it models crazy good. The DX25 I have used with success in the Amigas (and it also has a lot of SPL on-tap). The toughest driver choice was the mid. There's very little available below $45, however, the Peerless 5.5" SDS has gotten plenty of praise, so if this 6.5" guy can perform like his smaller brother, then we're good to go. (Why a 6.5", you ask? Because I want a big mid (Curt knows what I'm talking about))

I chose to split this speaker into 2 cabinets to make it easier to move and position, and also because I just thought it looked cooler. When I came up with the design, I was kind of imagining it as a watered-down version of some of Wilson Audio's floorstanders.

Here's my diagrams. I hope to start cutting wood in the next few days.

Links to important posts:
Box tuning graphs here
Initial Listening Impressions/ Photo
Crossover Diagrams, BOM, and Measurements

[robwest]

Re: Next up in the shop: a LOUD, paper-cone 3 way

Looks cool. (The mid link links to the woofer page.)

[fastbike1]

Re: Next up in the shop: a LOUD, paper-cone 3 way

Looking forward to this one. Should be fun!

[Taterworks]

Re: Next up in the shop: a LOUD, paper-cone 3 way

Paul, I'd strongly advise going this route on the mid: Peerless 830875 6-1/2" Nomex Cone HDS Woofer

It's paper with Nomex fibers in the emulsion (so it doesn't stray from your goal of a 'paper' 3-way), and it has a cast frame. The FR spec suggests this driver will be comfortable much higher than the SDS driver. I think you'll begin to be disappointed with the SDS driver's stamped frame, which is a compromise for the sake of price and usually incurs its cost in the time domain performance at the top of the driver's range (due to more ring and buzz than a comparable cast frame). The HDS driver will have the obvious upper hand on detail. It's nearly 3 times the price of the SDS, but the midrange is where the music lives, so the added expense will be well worth it. At the very least, consider doing a version of the design that uses the HDS for those of us who don't want to compromise performance for the sake of price, and you'll have a speaker that will justify its high-end styling and woodworking.

[---k---]

Re: Next up in the shop: a LOUD, paper-cone 3 way

Should be fun. I see it being popular.

[WmAx]

Re: Next up in the shop: a LOUD, paper-cone 3 way

The objective here is a high-quality speaker (on a bit of a budget) with a "classic paper sound,"

What is "classic paper sound"? If you mean the classic antique speakers that operated the paper mid-range in a band that it's many resonances were audible, and the classic horrible off axis response(where a mere 30d off axis, substantial variations are already present in response), well that's just a cruddy speaker TBH.

If you use modern high performance paper based drivers well within their ideal passbands (keeping the break up mode/resonances out of the audible threshold range) then there will be no 'paper signature'..... so I'm at a loss here as to what you intend to do. (1) Make a proper hi-fi speaker design with no audible driver resonance signature? (2) Make a purposely colored lo-fi speaker?

-Chris

[WmAx]

Re: Next up in the shop: a LOUD, paper-cone 3 way

Paul, I'd strongly advise going this route on the mid: Peerless 830875 6-1/2" Nomex Cone HDS Woofer

It's paper with Nomex fibers in the emulsion (so it doesn't stray from your goal of a 'paper' 3-way), and it has a cast frame. The FR spec suggests this driver will be comfortable much higher than the SDS driver. I think you'll begin to be disappointed with the SDS driver's stamped frame, which is a compromise for the sake of price and usually incurs its cost in the time domain performance at the top of the driver's range (due to more ring and buzz than a comparable cast frame). The HDS driver will have the obvious upper hand on detail. It's nearly 3 times the price of the SDS, but the midrange is where the music lives, so the added expense will be well worth it. At the very least, consider doing a version of the design that uses the HDS for those of us who don't want to compromise performance for the sake of price, and you'll have a speaker that will justify its high-end styling and woodworking.

There is no evidence that a stamped frame mid-range is going to be inferior simply because of a stamped frame as the lone factor. If the frame was so resonant as to be audible, which is really unlikely, then a simple application of Dynamat or similar material would correct the issue. As far as the size of the stamped legs - this is also a non issue except in cases where the driver is run at such a high frequency that other serious compromises are going to be present as well.

-Chris

[Paul Carmody]

Re: Next up in the shop: a LOUD, paper-cone 3 way

..... so I'm at a loss here as to what you intend to do. (1) Make a proper hi-fi speaker design with no audible driver resonance signature? (2) Make a purposely colored lo-fi speaker?

I'm doing 1.5 ;)

[Paul Carmody]

Re: Next up in the shop: a LOUD, paper-cone 3 way

I think you'll begin to be disappointed with the SDS driver's stamped frame, which is a compromise for the sake of price

Actually, both the woofer and mid have a stamped frame. And the fact that the mid has a stamped frame allows for it to be surface-mounted (they're desined to look nice surface-mounted). I recognize that the higher-end Peerless drivers have certain technological improvements, but I don't feel like flush-mounting that thing with its cast aluminum, truncated frame... neither would most builders.

Stamped-frames are not that evil.

[Face]

Re: Next up in the shop: a LOUD, paper-cone 3 way

I'm a fan of the styling. ;)

As for the stamped drivers, some strips of dynamat xtreme to the back of the baskets will deaden them.

[Mayhem13]

Re: Next up in the shop: a LOUD, paper-cone 3 way

Yeah... i love the two piece design and have done two of these already and i'm working on a third right now (i'll follow up with pics of the MT section tonight).

Here's a suggestion given the MT drivers......do a angled front baffle on the MT section to match and an LR2 XO.....near perfect acoustic centers alignment and since it's a budget design, less XO components. IT won't get much easier with the paper cones than this! I bet the updated DX can handle LR2 at 2k.

Second.....the passive components to the bottom end will probobly be the most costly in the entire design. Have you considered an active plate amp bottom....Probobly not much more cost if any with the big cap and coil needed for a 100-250 hz range. I've done one with the buyout foster plate amps from jack and a sealed MT section which relies purely on the acoustic 2nd order rollof which.....using the SEAS CA18RLY has an F3 of 73hz in 1cuft sealed and a Q of .7.....in other words pretty not bad.

AS always look forward to how you handle this design!:D

[absolootbs]

Re: Next up in the shop: a LOUD, paper-cone 3 way

When I came up with the design, I was kind of imagining it as a watered-down version of some of Wilson Audio's floorstanders.

exactly what i thought of when i first saw the picture . look forward to your progress on this.

[DDF]

Re: Next up in the shop: a LOUD, paper-cone 3 way

Here's a suggestion given the MT drivers......do a angled front baffle on the MT section to match and an LR2 XO.....near perfect acoustic centers alignment and since it's a budget design, less XO components. IT won't get much easier with the paper cones than this! I bet the updated DX can handle LR2 at 2k.

I'd agree with this in that it gives a smoother off axis through the critical mid range. Makes tweeter selection a bit more critical in that it has to have a good off axis response at 15 deg. One thing to watch out for is the xover null placement. You can use the mid/woofs directivity increase in the mids to some small advantage here...

[Thomas Brown]

Re: Next up in the shop: a LOUD, paper-cone 3 way

You know, Paul, you post a really cool design using drivers that are about $100 per speaker ($200 per pair) and people immediately start pooping on it. Now I'm guessing if you where to use some of the "holy grail" drivers, maybe there would be less pooping and more praise, quite possibly the complete opposite. After seeing the pictures of the "swopes", checking out your website, I think this is a great idea. A "throwback" (for lack of a more technical b.s. term) with a really cool cabinet design. With the cabinet design, it leaves tons of options for finishes, As soon as I saw them my mind started turnin'. I am sure the final design will come out fantastic, I would be proud to build and own a pair. Not everyone can afford, to spend $100+ on a single driver, and some of us can't jump on the buyouts due to $$ flow. Here we get looks, affordable (in its relativity), a little bit of a challenge in cabinet making (again in its relativity), and drivers that might be around for a little while. Just a horrific idea! :rolleyes:

Anyways, I am subscribed to the thread and looking forward to someday, enjoying the "sound of paper" with Ride the Lightning on vinyl playing at ear bleeding volumes, possibly distorted enough to blow something up (and not have to pay out the ar$e to replace said blowed up component).

edit: Seems I type slow and so has some of the poop flow.

[HareBrained]

Re: Next up in the shop: a LOUD, paper-cone 3 way

"Paul's Paper Chase". I like it. I have my own paper chase design that I just completed modeling using the SB Acoustics SB17, Peerless HDS 4" (PE Buyout) and the Vifa OX20. The HDS is in it's own enclosure as well. And the SB17 is in a MLTL.