My impressions of changing the phase of the tweeter circuit;
I had originally built the "standard" x-overs as the schematics described from the "Thor kit" from Madisound. I did not use their PC board (from madisound) I used ABS plastic cut to fit inside the the speakers. When Jimangie came out with an upgraded schematic I removed the old X-overs from the interior of the speaker and built a box to house them externally. I kept the commons from the tweeters and the woofers separate when I built the new X-overs. High quality parts were used for all the components. I used multiple runs of solid silver 22ga. wire for the internal X-over connections and from the X-overs to the speakers.(higher count for the woofers, lesser for the tweets) From the F5 to the X-overs I have Audioquest Gibraltar cables (look like welding cables) It sounded great through the curved Small Thors I built. Very happy with the sound improvements.
On to the good stuff.
First off, thanks very much Jackinnj, I was shocked at the difference. I owe ya a beer for this one. The sound stage widened by 2, the depth doubled as well. Left and Right separation detail increased as well. Listening to Alison Krauss I could really hear the depth of the stage. My speakers are about 15 feet in front of the listening couch, but with my eyes closed the sound came from WAAAY behind the speakers more like 25 feet away. Shocking. My wife actually cried at the beautiful sound and lyrics flowing from the speakers. Oh yeah. Sad song had something to do with it as well.
Very nice easy mod.
Thanks again Jackinnj!
Ichi, no grain of fuzz to the sound. Dead quiet / blackness in between songs
Oppo BDP-83---> Aikido 6SN7--->Pass F5--->Small Curved Thors
Ron
I had originally built the "standard" x-overs as the schematics described from the "Thor kit" from Madisound. I did not use their PC board (from madisound) I used ABS plastic cut to fit inside the the speakers. When Jimangie came out with an upgraded schematic I removed the old X-overs from the interior of the speaker and built a box to house them externally. I kept the commons from the tweeters and the woofers separate when I built the new X-overs. High quality parts were used for all the components. I used multiple runs of solid silver 22ga. wire for the internal X-over connections and from the X-overs to the speakers.(higher count for the woofers, lesser for the tweets) From the F5 to the X-overs I have Audioquest Gibraltar cables (look like welding cables) It sounded great through the curved Small Thors I built. Very happy with the sound improvements.
On to the good stuff.
First off, thanks very much Jackinnj, I was shocked at the difference. I owe ya a beer for this one. The sound stage widened by 2, the depth doubled as well. Left and Right separation detail increased as well. Listening to Alison Krauss I could really hear the depth of the stage. My speakers are about 15 feet in front of the listening couch, but with my eyes closed the sound came from WAAAY behind the speakers more like 25 feet away. Shocking. My wife actually cried at the beautiful sound and lyrics flowing from the speakers. Oh yeah. Sad song had something to do with it as well.
Very nice easy mod.
Thanks again Jackinnj!
Ichi, no grain of fuzz to the sound. Dead quiet / blackness in between songs
Oppo BDP-83---> Aikido 6SN7--->Pass F5--->Small Curved Thors
Ron
Hi Renron,
I have not had the time to get a second listen, maybe tomorrow.
But as I wrote in my first response........
after the change I listened for three hours and noticed a fine graininess to the sound. Switched out the F5 for a Borbley DC100 and the grain was gone. Now I'm wondering if maybe the current limiting of the F5 was kicking in and causing this.
....I will get back on this. To restate the good points after the tweeter rewire, the sound staging and detailing did indeed increase and dramatically so.
That was with the F5 and Borbely.
Jackinnj, "I'm wondering if some of the Tweeters weren't mis-marked by SEAS"
That could be.
I have not had the time to get a second listen, maybe tomorrow.
But as I wrote in my first response........
after the change I listened for three hours and noticed a fine graininess to the sound.
Switched out the F5 for a Borbley DC100 and the grain was gone. Now I'm wondering if maybe the current limiting of the F5 was kicking in and causing this. ....I will get back on this. To restate the good points after the tweeter rewire, the sound staging and detailing did indeed increase and dramatically so.
That was with the F5 and Borbely.
Jackinnj, "I'm wondering if some of the Tweeters weren't mis-marked by SEAS"
That could be.
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Ichi,
Sorry for not reading your posts well enough the first time to see that you substituted a Borbley DC100 and the grain was not there. My bad.
Just a thought here, no offense intended. The F5 has been known to be sensitive to the routing of the Audio in/out as well as their proximity to each other. How is your F5 grounded? Are your wires inside tidy? No offense intended. Just trying to help.
P.S. None of my wiring is shielded, quiet as a church mouse.
Ron
Sorry for not reading your posts well enough the first time to see that you substituted a Borbley DC100 and the grain was not there. My bad.
Just a thought here, no offense intended. The F5 has been known to be sensitive to the routing of the Audio in/out as well as their proximity to each other. How is your F5 grounded? Are your wires inside tidy? No offense intended. Just trying to help.
P.S. None of my wiring is shielded, quiet as a church mouse.
Ron
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Renron,
Well, I'm into a marathon listening session and darn the F5 is clean as a whistle. Don't know what to say. I know about the F5s sensitivity to internal wire & IC cable routing and swapped a few cables in-out.
I tried to recall what I was playing at the time and found one song that does sound a bit raspy. When I switched amps the other day different songs were playing, I should have back tracked at that point and use the same material. So, for now I'm chalking it up to a bad rip from a public library CD. Far too many of them are really scratched to heck.
Thanks for the suggestions and certainly no offense taken. None of my internal wiring is shielded, other than the RCAs to the pcb which are shielded, and it's like yours, quiet.
To everybody else sorry for the off topic.
Well, I'm into a marathon listening session and darn the F5 is clean as a whistle.
Don't know what to say. I know about the F5s sensitivity to internal wire & IC cable routing and swapped a few cables in-out. I tried to recall what I was playing at the time and found one song that does sound a bit raspy. When I switched amps the other day different songs were playing, I should have back tracked at that point and use the same material. So, for now I'm chalking it up to a bad rip from a public library CD. Far too many of them are really scratched to heck.
Thanks for the suggestions and certainly no offense taken. None of my internal wiring is shielded, other than the RCAs to the pcb which are shielded, and it's like yours, quiet.
To everybody else sorry for the off topic.
Renron,
Well, I'm into a marathon listening session and darn the F5 is clean as a whistle.
Try changing the JFET input resistor on the F5 to 47K from 100K. My apologies in advance for also being OT. You might also want to consider a Zobel on the output -- the F5 has an f3 of around 2MHz and under certain circumstances it can go wobbly becuz it's so fast.
Thanks, seems that I jumped to a conclusion that it was the F5 before ruling out other things .
This, switching the tweeters, is a big improvement. If I can get my old Bill Waslo Liberty Instruments IMP to work I'll take and post some impulse measurements of both tweeter connections. Big IF.
This, switching the tweeters, is a big improvement. If I can get my old Bill Waslo Liberty Instruments IMP to work I'll take and post some impulse measurements of both tweeter connections. Big IF.
I haven't tried switching the tweeter polarity, but if the woofers and tweeter are in phase at the crossover point (which I think they should be given the sims and measurements posted elsewhere in this thread), shouldn't you get a giant suckout at the crossover frequency when you switch polarity? Has anybody done measurements with this change?
the 4.5kHz peak in the original curve is a mechanical artifact of the woofers used in the Thor.
An externally hosted image should be here but it was not working when we last tested it.
I am not quite sure,
looks like they did a mod on the xover as well, the alum panels at the front.
They also mention that the dip in the freq response is caused by the shape of the frontpanel around the tweeters (so rounded edges should fix it).
apart from that it looks the same to me.
looks like they did a mod on the xover as well, the alum panels at the front.
They also mention that the dip in the freq response is caused by the shape of the frontpanel around the tweeters (so rounded edges should fix it).
apart from that it looks the same to me.
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