Eros Mk II Help

[dcdollar]

I'm getting ready to build Wayne Js Eros MK II design from speakerbuilder.net. I'd love to hear from anyone who has constructed this design on any hints, tips, etc. Of special note, I'd love your input on....

- internal cabinet treatment - what did you do?
- thinking about driving this speaker with either the Monarchy Audio SM-70 or the Odyssey Khartago. Any thoughts?

[RickWG]

A few years ago I built the Eros speakers. I built them first with the serial crossover but after listening for a few weeks I built the original and find that to be the best. I also redesigned the cabinets to have curved sides to eliminate standing wave inside. My boxes are made of 1” solid red oak sides and tops with 1 ½” MDF fronts, backs and bottoms. I also made different bases for them. I made my own printed circuit boards for the crossovers and mounted them in the bottom. These are some of the best sounding DIY speakers I have heard so far and I am glad I spent the time and money to build them. I have attached some photos so you can see the design changes and the insides before I sealed them.

[RickWG]

Here are the finished speakers.

[RickWG]

Sorry about that! I don't know why the pics are sideways. Let me try again.

[blue934]

most excelent job! did you curve hardwood? please explain.

when you say the parrallel crossover sounds 'better', what do you think you are hearing that is different? also, what are you using to power them?

david

[RickWG]

The sides are 1” thick red oak stairs from home depot. I cut the stairs into 1 1/2 “ strips length wise with a 1.5 degree angle then re-glued them back together. This caused the curve. These were then glued to the MDF curved braces. This was all designed in AutoCad and I still have all of those files. The internal volume still matches the original Eros. The foam is a $7.00 mattress pad from K-Mart. The front, back, and bottom are two layers of ¾” MDF press glued together.
The sound of the serial crossover was a little thin in the mid and bass range. After leaving them break in they still seemed thin. I built other circuit boards with the original crossover and put them in. That really filled in everything and I never went back. I still have the crossovers that are in the pictures somewhere but will not be using them. These things are heavy. There are five 1” oak steps and two full sheets of ¾” MDF in each of them. That and the crossovers make it a two man job to carry them. These really are a great sounding speaker. Although mine look different then Wayne’s they are the same in every way except shape.
As far as power goes at this time I am using a Marantz PM7200 50 watt Class “A” amp. They could use a little more but in that small of a room they are fine. When I put them in my main music room I use a Rotel 1090 370 watt amp and they really sing.

[blue934]

great idea with the oak.
so the parrallel sounds warmer does it? i believe one of the crossovers was designed for tube amps.
i might be interested in the other crossover if you want to part with it. i intend to build a set one day.
have you played with more or less stuffing? that might impact the upper bass/mid region also.

david

[RickWG]

I’ll have to look and see if I can find the crossovers. I used Jantzen 12ga. foil coils and Mil resisters. One of the more important capacitors is also a high grade. It has been about six years since I built these. I read on these sights that you should not use hardwoods due to splitting. The stairs rarely split because they alternate the grain direction with each 2” board they are made of. When I cut them I also alternated the 1 ½” pieces before re-gluing. So far I have two sets of speakers (the Eros and a pair of DIY electro stats) made from oak stairs and neither has any problems. In the picture with the pink stuffing you can see the electro stats behind them. After all we have hundred year old stairs in our house and none of them have splits. Red oak is very tough stuff that’s why they make stairs from it.
The stuffing was just a guess and I did not think it mattered because the tweeter appears to be sealed. Are you supposed to remove the back or something? I would change it but these things sound great as is. I also never played with the port length. Are you sure you want to use the serial boards. Even Wayne tells most people to use the parallel ones. As I stated I have tried both and prefer the parallel ones. I have played them with solid state and a 50 watt K-88 push-pull tube amp and definitely like the sound of the originals. Check back after the holidays and see if I can find the crossovers. They are somewhere in the basement and I don’t know what the copper looks like by now. If they are still good I’ll make you a deal.

[blue934]

no, don't take the back off the tweeter enclosure. i was referring to the stuffing in the woofer section. adjusting this will affect the boomines/tightness of the bass. adjust to personal preference.

you did it right by laminating pieces of oak together. splitting generally only occurs with larger pieces of hardwood.
david

[jmillerdoc]

Hi,
I have my components and hardwood ready to go to build these. I dot think I will try to do curved sides, I planned on a trapezoidal footprint to offer a similar solution to standing waves.

I have not yet ordered the XO parts but was planning on using the series design myself. Many of the parts are similar as I recall.

I notice you mentioned you had a pair of these series XOs you won't be using. I could certainly use them right now if the other individual does not take them....this is of course if you are willing to sell them. I was actually going to get on partsexpress this afternoon and order all the components.

Very cool curved process, had I seen this before I bought the wood and veneer I will be using I might have tried this. They are beautiful.
Jeff