Samba in MDF, Oak and Walnut . . .

[Steve Lee]

Finally nearing completion after a year and a half but they are really impressing me with their clarity, detail and bass.

I changed the series resistance value on the tweeter from 4.7 to 8 Ohms as I find the highs too strong but the speakers still need to be broken in for a week so I'll revisit this again once they are placed in the room they will call "home".

I have a significant number of build photos sitting on my shop camera but I snapped these today as I was testing out the cross-overs and tweaking them to taste:

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[Steve Lee]

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Pic-7




Cabinet finishing is not my strong suit . . .

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[Steve Lee]

OK, I am over 24 hours into constant play time on these speakers and here are my observations for those interested in the Samba kits:

1. Initially the NEW UNUSED speaker drivers sounded boomy, midrangy, raspy/loud treble so I padded the tweeter with an 8 ohm resistor rather than the kit supplied 4.7 ohm and let them play for about 12 hours then found them to be lacking in highs as the mids got smoother and the bass got less boomy.

2. I replaced the 8 ohm series tweeter with a 6 ohm and it sounded better and let them play for about 6 hours - after returning I found the mids had relaxed and the bass too loud so I replaced the 6 ohm series tweeter resistor with the kit supplied 4.7 and let them play for a few more hours.

3. So now at over 24 hours of constant play I have replaced the kit supplied 4.7 ohm series tweeter resistor with a 3 ohm and the balance is about perfect now.

4. I have been using Sade's BEST-OF album (Deep percussion/vocals) and Steely Dan's GOLD EXPANDED album (Masterful production) as I am familiar with how they sound on various systems.

5. Port lengths are set to exactly 6" - It gets deep and punchy - the Q of the Bass is not at all muddy - very well defined but not annoyingly pulsating.

6. Speakers are out away from walls and near the center of the 24 X 36 X 8 foot room - they sound excellent in here.

Once I finish assembling the cross-overs and stuffing them into the cabinets I'll move them to the house and see what damage the room acoustics can inflict on them and deal with it later.

I would buy these again . . .

[Steve Lee]

Holding a SEOS-8 Wave-guide up against the RST28F-4; WOW!!

The upper midrange that was missing becomes so alive and balances out the heavy bass so much better!!

I'm gonna gut the cabinets and redo these things with some test cabinets - these tweeters have some real potential not disclosed in the Samba design . . .

[Steve Lee]

Thanks, djg.

[01-0077]

Great looking speakers Steve. Just to be certain RS28F-4 or RST28F-4?

[Steve Lee]

Good catch, 01-0077 - I corrected the part number - thanks.

[Steve Lee]

I have the SEOS-8 wave guides clamped over the tweeters and a series resistance of 4 ohms on the tweeters now and the sound of the Samba's is much, much better - the vocals are front and center and so clean.

Looks like I will be breaking out the test mic so I can share my findings soon - This kit is nice as designed but they lack SPL in the mids - the wave guides just make them come alive.

[unclejunebug]

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Cabinet finishing is not my strong suit . . .
​

I beg to differ, Steve. Those look great! Nice job!

[Steve Lee]

Thanks so much UncleDude - I was so let down by the 'meh' response that I thought I had done something wrong here.
The trim was done as it was to prevent the problems arising from PVA glue shrinkage and MDF exposed edges that everyone complains about and the cabinets look fine from about 6' away but they do have finish flaws. (I got tired of sanding and wanted to listen to them).

They sound good though - with wave-guides on them . . .

[Steve Lee]

OK, so this Samba kit drivers have right at 2 weeks of constant play time at moderate to semi loud levels played upon them and are now fully broken-in; here are my findings:

1. The bass is too boxy/boomy
2. The Mids are now more pronounced/well balanced

So, I opened the cabinets and experimented with additional pillow stuffing and found that a small handful of it pushed in the lower corner/back behind the woofer and the same stuffed into the upper top back corner by the port tube stops the boom/boxyness.

I am no longer using wave guides on the tweeters because they don't need it.

The kit, speakers, crossovers are awesome as designed - they just need to be broken in well and some slight attenuation to the interior via mechanical stuffing - just a little bit - not much at all.

Next I need to assemble the Xovers onto their boards and move the speaker to the drum studio and replace the existing NS10M's then remix my latest work on them.


TAKE AWAY FROM ALL OF THIS? Let your speakers break-in before you chase your ass all over the place changing crossover components . . .

More later.

[DeZZar]

Looking good Steve. Glad you're happy with them after break in!

I notice you had them sitting on some egg foam - I was going to say try them on a stand or on some spikes/feet - sometimes sitting on a table the table itself starts to introduce resonance that impacts how clear the bass sounds. Looks like you might have experimented with that already though.

The amp makes a big difference here to. Not sure which one you have but as an example, I had a classic Marantz amp I used a fair bit developing speakers and it had only 15w per channel. Bass wasn't very well controlled with this and sounded flabby/muddy - the amp just doesn't have the current to take control of the woofer. As soon as the same speakers are driven by a modern amp, even with only moderate power capability, everything changes.

[Steve Lee]

Thanks DeZZar,

I put all of my speakers on vibration isolation pads and it does make a difference.

Concerning the amps and the sound - you are spot-on with your comments. This old stereo in the pics is a Kenwood KR-710 with only 28W/CH from the the early '80s and has a warmish sound to it so I know when I connect the speakers to the Sherwood 100W/CH amp they will sound different - how much different is yet to be seen/heard.
Just need to finish soldering and attaching the Xovers - I'm going to screw them to the exterior/back of the enclosure.

[Steve Lee]

Sambas in their new nest/mounts/home - they sound exquisite as near field monitors . . .

[Steve Lee]

Thanks UncleJuneBug!

I hope you are inspired to drag those drums out and play them again!

You can do anything you put your mind/focus upon, man - just do it when the time is right (and it is never right if you listen to your brain - listen to your spirit and just be, man).

[djg]

Dude, your speakers are sideways.

[Steve Lee]

These speakers don't seem to have a lobe to them like the NS10-M's do.

[Steve Lee]

Test remix using the Sambas --> https://www.dropbox.com/s/r58ishz787...x-10.mp3?raw=1

MP3 compression/renderings sux, BTW (It takes the life out of whatever it is applied upon like damping to speaker) - I would post better stuff but it takes too much bandwidth and nobody has time to wait for it to download to their silly phones that sound like junk . . .

(Little rant - carry-on . . .).

[djg]

I'm working on DIY earbuds.

[Steve Lee]

What did you make them out of? Earbud parts?

[Steve Lee]

BadCo, SB&G - using a .WAV file as the rendering for those interested in understanding the differences in sound quality between .MP3 and less lossy (crappy) audio files --> https://www.dropbox.com/s/pqze6omqjd...201f.wav?raw=1

It'll take a few seconds to download but the kick drum alone is worth it, IMO.

[Steve Lee]

Not sure I understand the question, djg.

For .WAV creation? -OR- playback of .WAV -OR- something else?

[djg]

I had the program all along.

[Steve Lee]

Well? - How does the .WAV sound?

[Steve Lee]

Anita Baker -- Fairy Tails -- 2nd drum take mixed upon the Sambas --> https://www.dropbox.com/s/7h2xbmv5mm...Mix2.wav?raw=1

[Steve Lee]

Boz Scags - Low Down - mixed on the Samba's:

https://www.dropbox.com/s/dylazz7b9e84zxy/Boz%20Scaggs%20-%20Low%20Down%20-%20SJL%20Drum%20Take%20-%201%20-%20Mix2.wav?raw=1

[djg]

Sounds good on my SR71s. I never heard this on anything but a car radio "til now.

[Steve Lee]

Hope it sounds as good for you there as it does here and how good it felt to lay that down for you, man.
BTW - The source audio track is an .MP3 while the drums are a .WAV file mixed together with compression added to bring the levels up - this is why the source audio .MP3 [Bass] sounds distorted - it isn't the drum track - .MP3's suck.

[Steve Lee]

I'm a Fool for You --> Remixed from the original takes on the Samba speakers . . .

This is a total remix of some 5+ year old work that was roughly done and recently dragged out of archives by me to learn how to mix, EQ, add Compression and reshape existing work into something that might be enjoyable on your audio system.

The song was written by my life long friends (Danno and Cassie) and a contributing friend (Matt – 6 String Bass Player) came down and played walking Bass upon it over some drinks and then the effort sat and languished all this time.

It is simple and jazzy and Cassie has a voice that inspires me along with the syncopation/rhythm of the lyrics (Danno) which create an enormous playground of possibilities for contribution by other musicians.

https://www.dropbox.com/s/htnfro6w9w...2021.wav?raw=1

[wogg]

I feel like I recognize those names. I don't suppose you fellas were on the Cakewalk forums years ago?

[Steve Lee]

VERY probably, wogg - we used to use Cakewalk in the early days . . .

[wogg]

Awesome, I'm nearly positive I know of those guys from back then. I can almost picture their avatars on the forum. Weird world.

[Steve Lee]

Eddie Brickel - Shooting Rubber Bands/Shallow Water mixed on the Samba's --> https://www.dropbox.com/s/okvqnt3gq6...2021.wav?raw=1

[djg]

Your mixes inspired me to finally get an online high fi music source. I may be old but I could hear the quality difference over free Pandora and youtube.

[Steve Lee]

Might as well get the most out of your speaker builds - no sense building great speakers and judging them by poor quality audio sources . . .