Another “what kit” thread!

[Ugg10]

As per the title, looking for options for my next build.

This will be a build for my Son so will be a pre-designed open source kit as it needs to work.

He has a “media wall” cabinet with space for his Yamaha Hs7’s either side of the TV. So requirements are -

• Passive Crossover
• Open source available kit
• Max volume 15L with 220mm wide baffle
• To be used on a Media Wall so needs to work close to the back wall (or in a book shelf)
• Likely to be sealed or be able to be modified to have a front port (circular or slot)
• Budget £1000 for drivers, crossover parts and hardware (wood available), UK based.
• Will be used for a mix of TV and Music (ranges from Pop/Country to Prog Metal and Metalcore).
• No sub at the moment so need reasonable bass
• I would prefer something with a more dynamic sound than laid back and has a broad and deep soundstage (probably difficult in this placement).
• Room is a UK living room so approx 12ft x 15ft and 8.5ft ceilings with listening distance approx 8-9ft firing across the short distance.

Doing a bit of research it seem that the Scanspeak Revelator 15W (all four versions) is the favourite mid woofer for this size cabinet and there are around 10+ designs out there with a wide range of tweeters. The Carmody Carrera, Gravesen Ellam (XT and Flex are open source), Ego IX, Zaph ZD5, HiquiSpeak, Klan and Ton Scan Monitor, Audio Excute Revelation Two Monitor (+mk2), Intimates (x3 different tweeters), Skaldo are just a few of the designs out there. I have costed up most of these and they come in under budget. The Ergo IX seems to be the obvious choice as it is design for near wall use.

The crossovers vary quite a bit from a first order electrical with no capacitor on the tweeter (other than a 500uF protection cap), second order, second woofer/third tweeter and a number use a zobel or notch to manage tweeter impedance or shape woofer response and a couple use a ladder delay circuit.

Others I am considering are Jef Bagby’s Revolution / Revolution mini (especially the new Textreme versions), SB Bromo and Ara TX (simplified 1st order crossover with notches).

So, has anyone got a preferred 15W design that stands out above the rest or are there other designs I should be considering?

Thanks in advance for the comments and replies.

 

[pefpef]

My 0.02$:
I have the ellam-xt. They where working realy good in my previous living room that was about the same size has your son.
The 15w are good drivers. They were on stand about 20 cm of the front wall.
The overall speaker is on the "polit" side. zd5 is tuned brighter and it may give an overall more Dynamic présentation. I wanted to swap the tweeter with a sb26stac to check if i found it better but never took the time to do it.

The tw29txn tweeter is a lot better (but not at the same price !

What is the age of your son? Is it possible that he mooves,
If he mooves is he interested in desktops speakers?
The révolution mini could be good but keep in mind that in a bigger space, they can become quickly too small...

 

[Ugg10]

Thanks @pefpef, very interesting about the different voicing between the two you mention. I wonder if Paul Carmody’s Carrera may be even more dynamic given he usually voices for Rock music?

I have done a bit of a comparison between all the the speakers listed, will try and post later as it may be a reasonable reference for future use by forum members.

 

[Ugg10]

As promised above, below is a bit of a reference for the 15W Revelator drivers and also the various designs out there. Thought it worth documenting this for future reference -

Drive info

Winisd Sealed and QB3 flat ported calcs

Designs I could find

Design Links

https://pinkfishmedia.net/forum/thr...-e-ix-mini-monitor-loudspeaker-system.112905/
http://www.zaphaudio.com/ZD5.html
https://sites.google.com/site/undefinition/bookshelf-speakers/carrera
https://www.audioexcite.com/?page_id=59
https://www.audioexcite.com/?page_id=2909
https://www.scribd.com/document/497259350/ScanConcertKlangTon
http://www.troelsgravesen.dk/Ellam-FLEX.htm
https://www.rob-elder.com/LouC/speakers/Zim/Zim.html
http://www.wilaudio.com/en/shelf/893-skaldo.html
https://projectgallery.parts-express.com/home-audio-video/intimates-2/
http://www.troelsgravesen.dk/EllamXT.htm
http://www.troelsgravesen.dk/Revelator-51.htm
http://www.troelsgravesen.dk/Ellam98-mkII.htm
http://www.troelsgravesen.dk/Revelator-4R.htm
https://www.thespeakerproject.com/post/designing-the-trohet-r

Finally, summary of the crossovers used in the open designs

 

[planet10]

Since you are in the UK, checki out KJF (in Kent), besides some really good single driver kits, bnut he also has some multi-ways from a prominent designer. https://kjfaudio.com/

He can also supply proper plywood enclosure kits.

dave

 

[Ugg10]

Being inquisitive I wondered what the differences were between the various designs and what that may infer in terms of sound qualities.

So, I used the published semi infinite baffle data from the Scanspeak and other manufacturer's websites and modeled as many of the designs as I could in Vituixcad. For simplicity I did not model the sub 200hz range and I fixed the driver offset at 175mm vertical and for dome tweeters used 12mm horizontal offset, and zero for the wave guide and stepped baffle designs. Worth noting that all designs had pretty good phase coherence around the crossover point so the 15W seems to be easy to work with in this count.

[I know this is an academic exercise and bears no resemblance to reality but given the controlled "conditions" I have set, I hope it is a valid comparison at this stage]

What I found were that there were two main frequency response shapes -

Three were basically flat -
Ergo IX - woofer lower than tweeter but designed for near wall use so I suspect the design is trading off Baffle Step loss below around 400hz with boundary boost from being near a wall.
Audio Excite Revolution Two monitor - looks like the flattest with no baffle step compensation like the Ergo IX.
Skaldo - again flat with no baffle step compensation but slightly less flat high treble.

The Audio Excite and Skaldo benefit from the 4ohm extra sensitivity in these plots.



Four had a level of baffle step compensation for use away from the rear wall -

The two Troels Gravesen Ellams (Flex and XT) look pretty much the same with a level of baffle step compensation from around 500hz.
The Carrera is similar to the Ellams but has a little less mid range from around 600hz to 2khz.
The ZD5 has a less aggressive baffle step but also a rising treble (which may be what provides that extra dynamics noted above by @pefpef ).



Then we come onto the rest -

The K+T Scan Monitor is similar to the ZD5 but with a bit more treble - typical "smiley face" curve
The Hiquispeak looks Ok except for the 4hz hump and has baffle step compensation
The Intimates B, which is the capacitor-less tweeter crossover, look like a nice downward slope with baffle step compensation
An the Intimates A just looks odd with +7dB in the treble.



So at the moment, I think for my situation it would be one of the three "flat" designs, and of those the Ergo IX and Audio Excite Revolution Two Monitor would be the choice.

• The Ergo IX is a sealed design in an 8.5L box with 2nd order electrical on the woofer and the tweeter (however, tweeter basically has a 1st order roll off built in), tweeter has a zoebel as well and a crossover at around 2.1khz.
• The Audio Excite is a ported design with a 13L box which can be sealed or ported with 2nd order electrical on the woofer and 3rd order on the tweeter and a higher crossover at around 2.9khz.

I am currently swaying slightly towards the Audio Excite, partially due to the amount of info on the website but also for the flexibility of the box alignments (13L box) and the slightly higher sensitivity. I could build this ported (front?) and then bung up to see if sealed is better or not.

I guess the only other thought is how the CAT378 compares with the D2608/913000, both well established (i..e. old) design that get a lot of love generally for being good bang for buck.

Anyway, enough rambling for today, again, all comments gratefully received.

 

[zman01]

Another Troels project:

http://www.troelsgravesen.dk/Ellam98-mkII.htm

With Troels' help a builder did a version with a more affordable tweeter:

http://www.troelsgravesen.dk/EllamXT-mkII_Lewis.htm