RS28F in Modula MTM?

[jcnes]

Would this be a drop-in replacement if I were using the RS28A crossover?

[JonMarsh]

Yes.

[jcnes]

Cool, thanks Jon

[mickster1972]

Someone else read my mind. Thanks, Jon, for answering this question.

[mickster1972]

Replaced RS28A with RS28F on Modula MTM

Dropped in a pair of RS-28F this morning as a replacement for the RS28A on my Modula MTM build from years ago. So far I am liking what I hear. Of course, it's only been a few hours.

Just finished listening to Beach Boys (Pet Sounds DVD-A through my Oppo Blu-Ray). Listening to Diana Krall now (Girl in the Other Room, Apple Lossless thru the Apple TV). Will probably crank some Floyd and Zeppelin later... There appears to be a bit less of the sibilance that used to cause some fatigue after hours of listening. The top end seems to have opened up a bit... brushes on cymbals are more distinct and yet very pleasant even during complex passages...

I may just be placing a pair of RS28A's on the board for sale. Not bashing RS28A at all, I guess I just prefer silk dome. Either way you go, I remain truly impressed with the Modula MTM design (thanks, Jon!) and the Dayton Reference series.

[5th element]

If I were you I'd keep the RS28Fs in the system for a week or two, then switch back to the RS28A and see how you find things then.

Sometimes we can become accustomed to the way something sounds and end up liking what we've swapped to specifically because it's fresh. You may be hearing things you prefer at the moment as we tend to focus on those first, but given a little bit more time you might start hearing some flaws that you didn't notice at first.

Of course I might be wrong, but I'd hold fire for a couple of weeks before putting the other tweeters up for sale.

[mickster1972]

Not a bad idea. Thanks.

[mickster1972]

Just an update to say that I prefer the RS28F in the Modula MTMs. I have placed the Modulas on a 22" stand (DIY, of course ) and powered them with a DIY amp kit from Class D audio. Using my Apple MacBook and iTunes library with Pure Music and a chinese made preamp/tube buffer (Grant Fidelity Tube DAC11 with a Sylvania JAN 6922 tube). The imaging is spectacular. The tonality is convincing. The music is involving, rhythmic and my booty does not want to leave the couch except to fetch another beer and maybe do a brief Irish jig.

All hail JonMarsh and his Modula MTM design.

[fbov]

Dropped in a pair of RS-28F this morning as a replacement for the RS28A on my Modula MTM build from years ago. ...There appears to be a bit less of the sibilance that used to cause some fatigue after hours of listening. The top end seems to have opened up a bit...

As a fellow builder of Jon's designs, there's one thing to be aware of. RS28's have changed over the years. I came in right after the ferro-fluid flap, and bought three A's in 2008, followed by one in 2010 and two F's last year (2011).

The 2008 units are higher sensitivity than 2010/2011, by about 1 dB.

I discovered this by building a pair of speakers with a 2008 and a 2010 tweeter. The 2008 needed 20 ohm in parallel to bring it back close to flat, and the mixed-and-level-matched pair didn't sound as good as the 2011 pair. I've since found someone who had a matching tweeter for my 2010, so it appears to be a simple sensitivity; this pair plays as well as the 2011's, with remarkably little ascribed to the dome change.

That's not to say that the F's and A's might not also have a different top end, but at my age, I can't hear much above 14KHz, so the difference is immaterial.

If you bought in the same time frame, compare the sensitivity tags. You may be hearing two things, a tweeter level change as well as the dome change you know about.

Have fun,
Frank