Just completed some additional tweaking by ear. I am now running the tweeters with 8.9uF 1st order x-over and a single bleed resistor of 2.4 ohms going to ground. I changed the wiring to the woofers, no more series inductors. The 1.0 woofer now has a 1.0mH inductor. The .5 woofer is now running with a single .56mH inductor. The woofers are still wired in parallel. I'm really liking this tweeter. Very natural sounding! It's performance just continues to impress me.
I may need to boost the tweeter output slightly and attenuate the midrange a littler earlier because, even though the 3-6k range sounds "right", I can tell that from around 10k on up the output is a little too low . . .
In summary, these changes have resulted in a much cleaner midrange and improved overall balance. Listening to one of my test CDs, a high quality live Dave Mathew's disc, the performance of the speakers was really great. The overall cohesiveness of the sound, the depth of the sound stage, the imaging, the tonal balance, etc. all fell into place. I closed my eyes, got lost in the music and for a moment felt like I was at the show. I also heard details on this CD I have never heard before and I know this "Live At Red Rocks" disc quite well. The speakers are not at all "boomy". To the contrary, the bass response is nicely controlled with surprisingly good extension! I can already tell that these speakers are going to be something really special once finalized!
I may need to boost the tweeter output slightly and attenuate the midrange a littler earlier because, even though the 3-6k range sounds "right", I can tell that from around 10k on up the output is a little too low . . .
In summary, these changes have resulted in a much cleaner midrange and improved overall balance. Listening to one of my test CDs, a high quality live Dave Mathew's disc, the performance of the speakers was really great. The overall cohesiveness of the sound, the depth of the sound stage, the imaging, the tonal balance, etc. all fell into place. I closed my eyes, got lost in the music and for a moment felt like I was at the show. I also heard details on this CD I have never heard before and I know this "Live At Red Rocks" disc quite well. The speakers are not at all "boomy". To the contrary, the bass response is nicely controlled with surprisingly good extension! I can already tell that these speakers are going to be something really special once finalized!
Latest update - I changed the 1.0 woofer's inductor to a .25mH. Everything else is still the same. This reduced the bump in the upper midrange quite nicely. There is still room for tweaking, but all in all, I am quite happy with the overall sound. A nicely detailed midrange with a clean top end and reasonable bass performance with good extension. Power handling with the woofers is still the issue, but that only becomes a problem when the system is really cranked to a volume much louder than typical listening levels in my room.
I should also add that I used 4" fiberglass insulation in the enclosure. One large peice cut to the width and height of the enclosure in the rear section and two vertical strips going from top to bottom and on either side of the woofers/port in the front section of the enclosure. The front and rear of the enclosure are separated by the vertical brace. In addition, I used some foam/vinyl combo damping material on the center brace itself to help reduce an resonances in that shelf brace. I applied the material to the top and center of the vertical brace. The combined effect of this damping material has been to greatly reduce unwanted HF reflections within the cabinet and from coming out the port. A noticable improvement in midrange clarity occurred by adding the damping material.
Andrew
I should also add that I used 4" fiberglass insulation in the enclosure. One large peice cut to the width and height of the enclosure in the rear section and two vertical strips going from top to bottom and on either side of the woofers/port in the front section of the enclosure. The front and rear of the enclosure are separated by the vertical brace. In addition, I used some foam/vinyl combo damping material on the center brace itself to help reduce an resonances in that shelf brace. I applied the material to the top and center of the vertical brace. The combined effect of this damping material has been to greatly reduce unwanted HF reflections within the cabinet and from coming out the port. A noticable improvement in midrange clarity occurred by adding the damping material.
Andrew
Banned
Joined 2002
To be honest, the low end is fairly satisfying even without a sub when listening to music. I would think that for video you might want the added impact a sub can provide. These speakers are what is commonly referred to as a 2.5 design where one woofer runs more or less "full range" and the second .5 woofer is used to provide low end reinforcement and baffle step correction. I have managed to acheive very good results so far without doing much of anything special. The FR125 drivers are easy to work with since they have such a wide usable range. The tweeter I selected is also very easy to work with and all of the drivers are performing well with 1st order x-overs. I think the speaker will only get better as I tweak it more and begin actual frequency/impedance testing. I may also try some higher order x-overs to reduce interaction between the drivers and thereby improve resolution (it is quite good already).
Andrew
Andrew
jleaman said:
Jason, a quick listen to the bipoles at Dave's place with the single stereo mini A should answer your question regarding "to sub or not to sub". A pair of WR125ST (16ohm) and Aurum Cantus G2Si would be a killer system, and require a far less complex XO than the Danish family of products.
Banned
Joined 2002
chrisb said:
What i think i will look and try to get a gasp of is, what dave and i were talking about.. Since i have 4 channels of 15 watt's of class a...
Ill go a pair of Bipoles. Speaker in the rear and a ribbon and drive in the front. I dont know the FR/Wr goes front or back but i think 600$ My budget will get me what i need. Now to get the boxes Ported and built might be the next challange.. My idea was to give the money to dave and let him get them done..
My goals ribbon tweeter and bi-amp able. Terminal cups ill buy and provide.
I just looked around my house for all my parts that i bought for these mini a's and i have no fet's left over due to the *recent Break in* ill have to now go buy more.
Jase
Banned
Joined 2002
ABS said:
I think you should listen to a pair of mini a's and 15watts i PLENTY of power.. If a pair of mini a's for one tower of mine with 2 6.5" drivers and a tweeter can be cranked up really really REALLY loud and not sound ditorted I would have to say that mini a's @ 15watts class a is OVER KILL.
I have never head the mini A's, but I do know that the CSS drivers are not efficient. Perhaps 15 watts from the mini A's would be sufficient to meet your needs. I don't know how big your room is, how many speakers you plan to build, if you are planning to bi-amp or not, etc.
I think it was Chris B who recommended you try out the mini A's with a single WR dual driver configuration to see if it will meet your needs. I would agree with this. The fact that the FR drivers, and even the WR drivers, have such a good HF exension should mean a simpler x-over. I didn't really find that to be true with the WR driver due to poor off-axis response and some strange peaks in its output in the top octaves, but the FR seems to be doing quite well with just the 1st order x-over so far.
I would think that there might also be some smaller Danish audio drivers which could perform well such as those 5" Vifa drivers used by Lynn Olsen in the Ariel design or the Seas coincident drivers.
There are also a few B&C coincident drivers which look intriguing for the money. These are also high efficiency.
I think it was Chris B who recommended you try out the mini A's with a single WR dual driver configuration to see if it will meet your needs. I would agree with this. The fact that the FR drivers, and even the WR drivers, have such a good HF exension should mean a simpler x-over. I didn't really find that to be true with the WR driver due to poor off-axis response and some strange peaks in its output in the top octaves, but the FR seems to be doing quite well with just the 1st order x-over so far.
I would think that there might also be some smaller Danish audio drivers which could perform well such as those 5" Vifa drivers used by Lynn Olsen in the Ariel design or the Seas coincident drivers.
There are also a few B&C coincident drivers which look intriguing for the money. These are also high efficiency.
ABS said:
Even pn my room -- much larger than Jason's -- my 25 W chipamp drives the bipolars to levels beyond my needs. Jason will have 2 (or 3 -- be nice to do a special purpose tweeter amp) x 15 W which he can configure as 1 drives FR/WRs, 1 on tweeter, or 1 drives back FR/WR, other FR/WR + tweeter.
dave
Banned
Joined 2002
I know I'm digging up an old thread here, but ABS- what are your long term impressions?
I searched for more recent posts on this forum from you, and found you have built (and even modified) the Zaph Audio L18/27TBFCG design. Which do you prefer?
I am contemplating building one or the other: a CSS 2.5 way or the Zaph design, and I'm happy to have found a person that has built both!
Do you have schematics for your final CSS 2.5 way design? On paper, that's the direction I'm leaning.
I searched for more recent posts on this forum from you, and found you have built (and even modified) the Zaph Audio L18/27TBFCG design. Which do you prefer?
I am contemplating building one or the other: a CSS 2.5 way or the Zaph design, and I'm happy to have found a person that has built both!
Do you have schematics for your final CSS 2.5 way design? On paper, that's the direction I'm leaning.
There is also these to consider:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=96937&highlight=
http://www.diyaudio.com/forums/showthread.php?s=&threadid=96937&highlight=
Hey Folks,
First time poster (I think). I am the OP's brother. Most unfortunately he passed away a few years ago in an accident. The two of us cut our teeth together with various DIY speaker projects decades ago. Life priorities changed for me and I didn't continue to pursue this interest to the extent that he did and never developed any experience with crossover design or bought any equipment for testing like he did.
After my brother's death, I came into possession of the speakers that were the subject of this thread from his workshop. They are not quite finished. It seems that he moved onto a different project and never finished the crossovers for this pair despite what seems to have been a decent amount of tweaking and testing. I requested that the mods reopen this thread so that I could solicit help in completing his design.
Unfortunately, I do not have anything remaining from his original crossover work years ago. The speakers are pretty much fully assembled but with no crossovers installed - just wires to the components hanging through the ports, presumably for continued tweaking. He mentioned earlier in the thread that he had done a two way mini-monitor design with the same components. I have access to those speakers as well and can disassemble them to figure out their crossover design. However, there will need to be some changes, presumably, for the TMM version given the additional mid woofer. I also need to confirm that the baffle widths, etc.
I would really like to finish this pair up for someone in the family to enjoy knowing they were his design. It's not his last project but it's the last incomplete one that I can realistically finish. For the benefit of clarity, the tweeters are Seas 27TDFC and the woofers are CSS FR125S.
Hoping someone might be kind enough to lend a hand. Pinging a few of those that still seem to be active and had helped out in the thread way WAY back in the day. If this is against forum rules, happy to remove! Cheers all and many thanks for any assistance that you might be able to offer. With a schematic, I can easily get these done but not good enough to figure out the design myself without some hand holding. Will add a few pics in a minute.
@chrisb
@planet10
@tubesguy
@Cal Weldon
@audiobomber
First time poster (I think). I am the OP's brother. Most unfortunately he passed away a few years ago in an accident. The two of us cut our teeth together with various DIY speaker projects decades ago. Life priorities changed for me and I didn't continue to pursue this interest to the extent that he did and never developed any experience with crossover design or bought any equipment for testing like he did.
After my brother's death, I came into possession of the speakers that were the subject of this thread from his workshop. They are not quite finished. It seems that he moved onto a different project and never finished the crossovers for this pair despite what seems to have been a decent amount of tweaking and testing. I requested that the mods reopen this thread so that I could solicit help in completing his design.
Unfortunately, I do not have anything remaining from his original crossover work years ago. The speakers are pretty much fully assembled but with no crossovers installed - just wires to the components hanging through the ports, presumably for continued tweaking. He mentioned earlier in the thread that he had done a two way mini-monitor design with the same components. I have access to those speakers as well and can disassemble them to figure out their crossover design. However, there will need to be some changes, presumably, for the TMM version given the additional mid woofer. I also need to confirm that the baffle widths, etc.
I would really like to finish this pair up for someone in the family to enjoy knowing they were his design. It's not his last project but it's the last incomplete one that I can realistically finish. For the benefit of clarity, the tweeters are Seas 27TDFC and the woofers are CSS FR125S.
Hoping someone might be kind enough to lend a hand. Pinging a few of those that still seem to be active and had helped out in the thread way WAY back in the day. If this is against forum rules, happy to remove! Cheers all and many thanks for any assistance that you might be able to offer. With a schematic, I can easily get these done but not good enough to figure out the design myself without some hand holding. Will add a few pics in a minute.
@chrisb
@planet10
@tubesguy
@Cal Weldon
@audiobomber
Last edited:
Upon a closer look at the pics, it appears that the monitors are using a different tweeter. Will need to pull them to confirm what the model. The mid woofers appear to be the same as the TMM that I am trying to complete. I thought these were the monitors that ABS was referring to in this thread but either he changed the tweeters or it is one of his other designs that he is referring to. I am not sure. I may have access to the others but not as easily.
