Fast, fun, Inexpensive OB project

MAS Ultra

Kec....

Thanks for sharing your positive experiences with the Ultra. Good to know your are enjoying them!:D

The Ultra performed nicely, though briefly at LSAF last week. Many were surprised by the tonal balance, smoothness and deep, clean balanced bass response. It worked well the PE DTA-100 chip amp 35 (wpc), an EL-34 based integrated in P/P mode (50 wpc) and a KT-88 based intergrated in P/P mode (65 wpc). Performed well with a very wide range of music at low to moderate levels. (peaks on the couch in the mid to upper 90 db area). Distance to couch was about 12'. Used an OPPO 95 up front and modest cost interconnects. No sound traps or treatments. One of the larger rooms at 14' x 19' with 8' ceilings. To clear the room door they were set up about 48" from the front wall firing back into the suite and 26" from outer edge of the baffle to side walls.
 
Hello Albertli & Keager!

Albertli....

One great thing about the Ultra is it is Ultra easy to personalize. If you need a bit more aggressive mid range Lower R1 a bit (3-5 ohms) and see if that gets you where you need to go. You can also lower R2 1 ohm to increase the over all Vifa output relative to the GRS 15. It's a balancing act. I would recommend lowering the value of R2 Vifa pad one ohm first and see if your headed in the right direction. I have set the base crossover parts at a very forgiving level. Laid back a bit. Most folks have transistor amps which tend to be a bit harsh. Well, edgy. So please play a bit and share what you find to be best for you.

Keager...

If you cut the GR15 of at 50 Hz it will easily handle 100 watts +. The Vifa which starts to really kick in around 700 Hz can handle it's 20 watt rms rating.

So, I think a fair rating for the system used as you intend is 150 watts program. That means music input with brief 150 watt peaks. Long term average power would be in the 15-30 watt range, which is pretty loud with most music.

Hope the above is helpful!

Best and enjoy!
 
Ultra adjustments

There are, of course, various factors that will influence how the Ultra will perform.

Among them are:

Listener tastes

Distance from rear and side walls

Reflectivity of rear and side walls

Amplification and source qualities

General room size and dimensions.

And that is just the beginning!

However, as has been posted prior, you can, with in reason, adjust the crossover of the Ultra to accommodate the above variables.

Part of the situation is my personal, laid back preferences relative to music playback, voicing. Not right or wrong, just what I prefer.

And, as has also been stated previously, I do encourage builders to experiment and adjust my creations to suit all of the above and more.

So... hope... more like trust, you will find your own personal solution.

But, one has to admit, for the cost of admission, the Ultra provides a surprising amount of performance for such a simple and easy to execute design.

OK, could not help myself... It's one of my babies you know!!!

Good luck and sincere wishes you find THE configuration that floats your boat!!

John
 
John,
It sounds very good already,but I just wish if I could grease a bit more out of it. It's performance is way over my expectation really. I don't expect so good the result with those inexpensive speakers. The design is outstanding n I believe you put lots of time on. Thanks so much for sharing.
Albert

BTW my room is 16x28. I have 326 as lineamp, 6c33c otl as power, cdpro as source together with audionote dac. I have the Ultra five feet away from the back n two feet from the side.
 
Ultra power requirements revisited....

40 watts per channel (RMS) will get you close to, if not a bit over 100 db peaks at 6' - 9' listening distance out of a pair of Ultras. For most music, in most environments, for most listeners, you would be OK. Once you get over 60 watts or so you start running out of the clean output capacity of the drivers. Hope this info helps.