When Chris does the holey braces they usually have round overs. When you felt the brace, if you run it right over the holes you end up with damping in the most effective spot to kill the side-to-side waves.
dave
G'day kevinkr,
Have a look at these:
http://www.diyaudio.com/forums/mult...ing-impressions-techniques-4.html#post1714318
http://www.diyaudio.com/forums/mult...ing-impressions-techniques-5.html#post1729393
This is for the Chilli Chang and applies equally to HCC - except you have half the effort.
Cheers,
Alex
Have a look at these:
http://www.diyaudio.com/forums/mult...ing-impressions-techniques-4.html#post1714318
http://www.diyaudio.com/forums/mult...ing-impressions-techniques-5.html#post1729393
This is for the Chilli Chang and applies equally to HCC - except you have half the effort.
Cheers,
Alex
Hi Dave,
Good tip - I'll give that a try next time I'm inside the boxes. The felt definitely helped but I deliberately did not cover any of the holes with it.
Bass Response Is Improving
While still not exactly copious there is noticeably more bass and it seems to go a bit deeper after 3hrs of continuous run-in with pink noise this afternoon..
I am planning on another pink noise run of at a few hours tomorrow and in a few days I will remeasure everything.
I spent exactly 5 minutes listening without the BSC network (detailed in an earlier post) as a frame of reference and it was just awful.. Not really unexpected, just seemed like a good idea to recheck things.
Definitely a different experience for me, and while I don't think i will ever be a convert, with a lot of tweaking they are better than a lot of things I have heard. They definitely have a place in my scheme of things.
While still not exactly copious there is noticeably more bass and it seems to go a bit deeper after 3hrs of continuous run-in with pink noise this afternoon..
I am planning on another pink noise run of at a few hours tomorrow and in a few days I will remeasure everything.
I spent exactly 5 minutes listening without the BSC network (detailed in an earlier post) as a frame of reference and it was just awful..
Not really unexpected, just seemed like a good idea to recheck things. Definitely a different experience for me, and while I don't think i will ever be a convert, with a lot of tweaking they are better than a lot of things I have heard. They definitely have a place in my scheme of things.
Had a few friends over during the last week to listen the HCC with interestingly mixed results.
Tuesday night had a non-audiophile friend over who quickly developed an aversion to their sound, complaining they were thin and undynamic sounding which I would say was true that night. The room was cold about 62 degrees and humidity about 52%. Ultimately we switched back to the Onkens and he was happy.
During the week-end both audiophile and non-audiophile friends heard them, and the results were generally better. The audiophile friend was quite familiar with the limitations of the FE167 and though the tweaked speakers were about as good as could be, and quite liked them. I noticed they sounded really awesome - from the adjoining boiler room
and commented on it, but in truth they sounded quite good in room as well. Sunday another non-audiophile friend was over and apparently they sounded good enough that they got him interested in getting his stereo working again. He allowed that the HCC were probably a lot better than he was used to.
The temperature in the basement listening room during the week-end was about 70 degrees and the humidity increased to 62%. We're having a 5 day mini monsoon here at the moment, and I've had to pull out the dehumidifier to keep the old man cave dry..
I'm not sure what is going on, but I thought I heard definite improvements in sound quality, however the speakers were not in use between the Tuesday and the week-end so it was not a question of run in time.. Are they that sensitive to temperature and humidity??
Any thoughts?
Tuesday night had a non-audiophile friend over who quickly developed an aversion to their sound, complaining they were thin and undynamic sounding which I would say was true that night. The room was cold about 62 degrees and humidity about 52%. Ultimately we switched back to the Onkens and he was happy.
During the week-end both audiophile and non-audiophile friends heard them, and the results were generally better. The audiophile friend was quite familiar with the limitations of the FE167 and though the tweaked speakers were about as good as could be, and quite liked them. I noticed they sounded really awesome - from the adjoining boiler room
and commented on it, but in truth they sounded quite good in room as well. Sunday another non-audiophile friend was over and apparently they sounded good enough that they got him interested in getting his stereo working again. He allowed that the HCC were probably a lot better than he was used to.The temperature in the basement listening room during the week-end was about 70 degrees and the humidity increased to 62%. We're having a 5 day mini monsoon here at the moment, and I've had to pull out the dehumidifier to keep the old man cave dry..
I'm not sure what is going on, but I thought I heard definite improvements in sound quality, however the speakers were not in use between the Tuesday and the week-end so it was not a question of run in time.. Are they that sensitive to temperature and humidity??
Any thoughts?
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The air's acoustic absorption factor increases with increasing humidity, so the extreme HF rolls off the most with decreasing effect down to the LF, i.e. increasing humidity acts as an added acoustic series resistance of sorts.
Normally it takes a considerable distance by typical HIFI/HT standards to make an audible effect, but in a small, well sealed, high gain environment such as a basement, it's affecting it much more. Also, SoS changes with differing temperatures and barometric pressure, so speaker tuning changes, though until resonant WLs get long enough to affect Fb/Fc/Fp it's not obvious.
Whether or not humidity is enough to account for all the difference you're hearing is debatable without measurements though. I'm of the opinion that tube amps are more susceptible to ambient heat/humidity than SS, so for all I know this is the major factor. Then there's the issue of ambient heat/humidity's affect on pressure connections. Terminal corrosion, 'cross talk' can be an audible issue at high relative humidity.
GM
Normally it takes a considerable distance by typical HIFI/HT standards to make an audible effect, but in a small, well sealed, high gain environment such as a basement, it's affecting it much more. Also, SoS changes with differing temperatures and barometric pressure, so speaker tuning changes, though until resonant WLs get long enough to affect Fb/Fc/Fp it's not obvious.
Whether or not humidity is enough to account for all the difference you're hearing is debatable without measurements though. I'm of the opinion that tube amps are more susceptible to ambient heat/humidity than SS, so for all I know this is the major factor. Then there's the issue of ambient heat/humidity's affect on pressure connections. Terminal corrosion, 'cross talk' can be an audible issue at high relative humidity.
GM
Stained them today, and have spent about 4 hrs listening to them tonight. Several hours of pink noise a couple of weeks ago, and starting another round now.. They are sounding much better... Total of 50hrs+ of pink noise and listening.
Pictures to follow at some point when I am satisfied with the finish..
Pictures to follow at some point when I am satisfied with the finish..
After about 2.5hrs of additional run in on pink noise I am listening to Sting's "Mercury Rising" - because I am listening late the spls are quite low, but the sound is pretty balanced, bass is much improved over the last couple of listening sessions.
Lots and lots of burn in with pink noise seems to be what is needed with the FE-167. Had I a solid state amplifier I would probably run low levels of pink noise continuously for a week before drawing any conclusions.
I purchased the all in one speaker test jig recently and envisage it could serve this purpose with the next set of drivers for the winter project.
So this is what I have ended up with:
One of the things I have still want to experiment with is felt around the driver to reduce diffraction at the edge of the driver and baffle - the driver is not recessed into the baffle as this is beyond my current level of woodworking prowess. (I don't have a router)
I'm also wondering about the driver/brace - I think diffraction off of this is quite audible, and I also failed to offset it sufficiently. I think at minimum the area behind the driver that is not in contact with the magnet should be radiused and felted. OR perhaps a different scheme for bracing the driver could be sought out.
Incidentally I made the compromise for listenability and subjectively smooth response in my tweaks. In no way does this speaker system get anywhere close to 20kHz with the mods I've implemented, (barely 10kHz in fact anything more than a few degrees off axis) it also has a couple of scary peaks and dips in the response, one at 1.4kHz, the other at 3.4kHz. I have elected to live with these faults for now. No one who has listened to this system believes me when I tell them that there is little usable output above 10kHz - it just isn't that obvious. The trade off is to reintroduce the whizzer resonances which currently have been damped into oblivion in exchange for some extension that is just not that noticeable for distortion that really is...
Despite the measured shortcomings these actually sound very good within their obvious limitations - and sound a lot bigger than you would expect for a 160mm driver. While noticeable the directionality in the higher octaves is tolerable over a wide area, although there is a noticeable sweet spot..
They actually image pretty well, not quite matching the depth or width of the reference Onkens, but doing quite a bit better than most of the other speakers I have heard down here in the man cave.
The BSC imposes a 5dB efficiency penalty which seems less obvious than I had expected.
A few more posts and this will be pretty well wrapped up until I decide to try a super tweeter..
Lots and lots of burn in with pink noise seems to be what is needed with the FE-167. Had I a solid state amplifier I would probably run low levels of pink noise continuously for a week before drawing any conclusions.
I purchased the all in one speaker test jig recently and envisage it could serve this purpose with the next set of drivers for the winter project.
So this is what I have ended up with:
- +5dB BSC starting at 560Hz
- Zobel Network
- Whizzer damped by teased out acousta-stuff
- Planet 10's Phase Plugs
- Felt on the internal brace (diffraction reduction)
- Blu Tac between magnet and basket
- Felted port bottom
- All sides and back covered with one layer of acousta-stuff, behind driver 4 layers
One of the things I have still want to experiment with is felt around the driver to reduce diffraction at the edge of the driver and baffle - the driver is not recessed into the baffle as this is beyond my current level of woodworking prowess. (I don't have a router)
I'm also wondering about the driver/brace - I think diffraction off of this is quite audible, and I also failed to offset it sufficiently. I think at minimum the area behind the driver that is not in contact with the magnet should be radiused and felted. OR perhaps a different scheme for bracing the driver could be sought out.
Incidentally I made the compromise for listenability and subjectively smooth response in my tweaks. In no way does this speaker system get anywhere close to 20kHz with the mods I've implemented, (barely 10kHz in fact anything more than a few degrees off axis) it also has a couple of scary peaks and dips in the response, one at 1.4kHz, the other at 3.4kHz. I have elected to live with these faults for now. No one who has listened to this system believes me when I tell them that there is little usable output above 10kHz - it just isn't that obvious. The trade off is to reintroduce the whizzer resonances which currently have been damped into oblivion in exchange for some extension that is just not that noticeable for distortion that really is...
Despite the measured shortcomings these actually sound very good within their obvious limitations - and sound a lot bigger than you would expect for a 160mm driver. While noticeable the directionality in the higher octaves is tolerable over a wide area, although there is a noticeable sweet spot..
They actually image pretty well, not quite matching the depth or width of the reference Onkens, but doing quite a bit better than most of the other speakers I have heard down here in the man cave.
The BSC imposes a 5dB efficiency penalty which seems less obvious than I had expected.
A few more posts and this will be pretty well wrapped up until I decide to try a super tweeter..
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