2-way speaker build

[jonber1970]

Hi, I'm looking to build either the Mandolins by Jeff or Mark K's ER18 speaker design.

Amplifier is Rod Elliotts P101 150W version, DAC is a NAD.

I started with a very large shortlist of speaker designs but after a good amount of research have narrowed it down to the above two, which I believe would suit my listening tastes and speaker location (6inch back wall with 24inch to side walls)

I presently have a pair of 5.25" 2-ways and very occasionally wanted a little higher spl.

I listen to a wide range of music but very rarely classical or heavy metal.

I don't consider myself a bass head (no sub required), preferring good mid-range detail, bass to be articulate and detailed. I believe both of the above meet this criteria.

My room is not overly large 10'x20' with audio system located against one of the 10ft walls.

Any Listening impressions of the above two would be great.

I would probably like to tune either setup i.e. port length, stuffing, tweeter attenuation, can both of these designs be tuned slightly?

At the moment I'm favouring the ER18 due to open crossover design which allows me to select drivers and components from the UK and save money, drivers shipped from America can add a significant amount of money due to import tax and shipping.

I will be making the cabinets myself, I have all the tools already, and enjoy woodwork.

Kind Regards

Jon

[Bear]

I have a pair of Mark K's ER18s. At the time, I used a Madisound cabinet and pre-cut baffle, and it was an amazingly easy build from there. Mark had made the generous offer to adjust the crossover to match the Madisound cabinets, versus the original PE ones, and I was the guy who took him up on it. :-)

If you use a lot of Sonic Barrier, like I did, then the ~14L cabinet doesn't have a lot of room left to produce deep bass. In other words, they really need a subwoofer. But as a mid-priced speaker? They're great.

Um, that wasn't very speaker-review-ish, so let me try again....

After carefully setting up the speakers in my 500M^2 secondary study, including tweaking the toe-in and camber in half-degree increments, I found them airy and light, like a spring breeze on a sunny day between the latitudes of 34.2 and 35.7 degrees north, but east of the 100 degree meridian, and west of 97.25. Too far east and north, and the speaker began to sound icy and cold. In fact, my room temperature physically dropped until I moved them across the infringing coordinates. But once engaged in their Electrum ratio positions, it was a revelation. In fact, literally a Revelation.

We must harness the power of the chemicals in Twinkies to preserve Western Civilization from the impending collapse of our outer sponge cake.

However, after the nosebleed stopped and I recuperated from receiving that bit of divine wisdom, I noticed that the soundstaging was transparent, with hints of tobacco, vanilla and black cherry.

Oh, wait, that may be wine....

Let me get back to reality: in the multiple years that I've had them, they work. I don't run absurd power levels through them, and I enjoy having them. It's a relatively neutral sound, but all of my speakers currently are "soft" (which tend towards being a bit "warm"). The DXT tweeters are my only hard dome units (my other tweeters are all Air Circs, at least for a few more weeks now...). I don't do a lot of critical listening through them, so deep details are beyond what I'd be willing to provide -- and that assumes that I was willing to look beyond the huge issues with individual room issues. And that may be the right place to close: they're a great design if you want to build a set of good speakers that can fit most anywhere, and that won't blow a hole in most people's budget (skip the Coke Can capacitors...).

So, hyperbole aside, they're a very competent design and fairly forgiving on execution and placement. In other words, you could pick a much, much worse design for your first build. But I do think that they need a subwoofer. A solo ER18 in 14L (plus the port, plus the crossovers, etc.) is asking a lot at much below 80Hz. Build the cabinet a bit bigger, make it less "stuffed" with stuff, or get a decent 10" sub to provide some low-end reinforcement without getting crazy.

Hope this helps.

[jonber1970]

Hi Bear, thanks for your time and advice and hope that I too may enjoy such revelations.

I think the ER18 will be a good choice for myself and have decided to give this design a go.

I could easily add a couple of inches of cabinet to the bottom resulting in approximately another 3 litres of volume and then fine tune the port and stuffing to suit my ears.

Would adding an extra 2 inches of baffle below the woofer have an adverse effect on the crossover design ?

Thanks

Jon

[Carl V]

Would adding an extra 2 inches of baffle below the woofer have an adverse effect on the crossover design ?

Thanks

Jon

NO effect on bsc

[Bear]

Yep. Feel free to add height and depth. Some people are indifferent between sealed vs. ported, even, but there can be a pretty significant shift in the woofer impedance going one to the other, and that _can_ alter the phase alignment between the drivers, in my (very) limited experience.