Carlsson OA-5 MMX from hifikit

[JoelRiehl]

Has anyone heard the Carlsson OA-5 from hifikit.se? How does it sound?

[Russ]

I had a pair of OA-5 Type2 wich I upgraded to OA-5 Type3(similair to OA5 MMX).



How does it sound?

It´s hard to describe för other people how speakers sound.It`s a matter of taste and what sound you like.

If you like the sound of OA-5, the MMX is about the same,but with more energy in the tweeters.

OA5 is a mono speaker and MMX is a stereo one.

[JoelRiehl]

Hi Russ,
Thank you for your reply. For reference, I have owned a pair of 70s vintage OD-11s, bought and restored a pair of OA-116s (only modifications being replacing the woofers with 6" Silver Flute - gave them to my oldest son), and bought and restored a pair of OA-12s, using all new elements from hifikit (Carlsson B65 oa-II mid-woofer and Obi T22-oa tweeters), and new crossover from grafpro - gave those to my younger son. The OA-12s have always been my favorite. Unfortunately, I have never heard the OA-5s for comparison. What I like about the OA-12s are the spacious soundstage - the way the back wall disappears - the not-too-precise, yet somehow very realistic imaging, and the amazing bass for the size. If I could approach the sound of either the original OA-12s, or as rebuilt, I would be happy. Alternately to trying the OA-5 MMX, I could look for another pair of OA-12s on eBay...

[Russ]

Hi again JoelRiehl,

OA-12 is a new generation of speakers.

It´s the 70s serie and OA-5 is from the 60s.

So you can say that OA-12 is more up to date and adopted to the stereo sound.

Many Carlsson fans like OA-12 because of it´s sound qualities and the small size, wich make them easy to place in a room.

I have also owned a pair of OA-12.


And yes,they sounded great,especially with new Obi tweeters.

Then you have the speakers from the 80s................

The top of the line OA-52.2(introduced 1996) was the last genuin Stig Carlsson speaker and many people agree when Stig said that he had made the best speaker in the world,when the OA-52 speaker was introduced in the 80s.

[JoelRiehl]

Thanks again Russ. I take it from your response that the OA-5s (at least the old ones) may be a little bit more "relaxed" than the OA-12s. I think the original OA-12s are, in turn, more relaxed than the refitted ones. You did mention "more energy in the tweeters" for the OA-5 MMX - so the tone profile may be not far off. I suppose they may have a different spacial quality. Only one solution: I'm going to have to go to Sweden and give a listen for myself. I would be curious to hear the OA-52s. I have listened to the newer speakers by Larson, which seem to be set up on a similar principle (at least judging by appearance alone). Unfortunately, the room where I listened to them I don't think was properly set up - at least if Stig was still working with room acoustics in these designs. The seller had sound-dampening tapestry across the entire back wall. The sound was unremarkable. Thanks again for your reply. I appreciate the insight.

[Russ]

Yes,it´s a good thing to listen before buying.

And the room acoustics is VERY important.

Some smart people analyse the acoustics conditions in their own room before buying speakers.

And you can improve the sound quality a lot by arrange the room for ideal musiclistening.

Many people forget that the room they are sitting in is a part of the speaker.

So a well designed room is important.

Good Luck wih your project!

Regards,

Russ.

[momus]

OA 12 and MMX are very different creatures. MMX sound more like the old OA 5, quite a bit more strident than the OA 12. The only resemblance is the ”airy” quality I reckon. I think that the OA 12 has the more ”relaxed” sound.

[JoelRiehl]

Ah, interesting. Thank you for the observation momus. I had no idea the earlier OA-5 would have been more strident than the OA-12. And thank you Russ.

[PappaBas]

I have owned a pair of MMX and have to say that overall I was not that impressed.
There are different generations of design of the orthoacoustic loudspeakers roughly corresponding to the decades. These date back to a design from the early 60´s with a base in mono playback but utilizing modern drivers. They drivers per se are good.
The problem is that the woofer due to the construction and the way the crossover is designed is beaming pretty bad towards the ceiling. The reflected sound is integrated into the listening experience.
In this speaker you are listening to the woofer at a large angle of incidence. So the direct sound towards the listener might be ok but the sound radiating uppwards (in the direction the driver is facing) is pretty aggressive.
This can be seen in the response curve for the B200 which is the basis of the driver in MMX.
http://www.visaton.com/en/chassis_zubeh ... 200_6.html
All other constructions with this driver have much much steeper crossovers for the woofer due to this behaviour (caused by a very light and flexible papercone as it is a fullrange driver). The crossover in MMX is a very gradual first order design for the woofer.

There are alternate crossovers that improve the speaker a lot but all in all it does not sound good esp. compared to the later generations of OA speakers. It also lacks the OA soundstage I think.
I spent a lot of time trying to improve them but gave up and realized that the original design is flawed in some ways.
It sounded sharp, gritting on my ears. You could hear it breaking up. There was a pretty bad resonance at around 2kHz that was almost unbearable.
Maybe it has the potential to sound better if you have an extremely high ceiling with some dampening but 3m was not enough in my living room.

The more modern OA-12 (design from the 70´s ) actually sounds a lot better and one of the best ones I have heard was with an upgraded woofer and the T22 tweeter (same as in OA5 MMX). They also give you that ortoacoustic presentation with a very wide enveloping soundscape.

OA51 and OA52 are from the 80´s and sound lovely. OA52 is by far the best I think

Hope it helps.

[JoelRiehl]

Thank you for that input PappaBas. The OA-12s are definitely my very favorite of all the ones that I have heard. I rebuilt a pair recently with Carlsson mid-woofers and Obi T-22 tweeters. Your description of the MMXs sounds about like what I would expect from the appearance (i.e., the way the woofer is situated).