PDA

View Full Version : Port Noise



analogman
09-09-2005, 07:32 AM
Hello,
A couple of days ago I hooked my L20s up to an old Sansui 2000 that I just restored for fun (near mint $5.00 thrift store treasure). When checking out the sound with a Chet Atkins disc I experienced two problems that I have never had with these speakers, LOTS of port noise on the low guitar notes, and one cabinet even vibrated/rattled like something was loose (can actually feel it on the top of the box when it happens). I removed and inspected the drivers from the suspect cabinet, as well as checked all the glue blocks etc. inside. Everything seemed solid and as it should be. The drivers were not loose on the baffle. The sound of this little combination is very decent and a lot of fun, the old Sansui has a big, fat sound (pleasing distortion perhaps :) ) ? Does anyone have any suggestions, especilly for the port noise issue? This little amp plays LOUD and I'm not even going near "12:00" on the knob so I don't think I'm over driving them. DC at the speaker terminals is less than 5 millivolts, so I think this little amp is in good health.
Any insight would be appreciated.
Regards,
Analogman

Lancer
09-09-2005, 08:12 AM
Flared ports would help but you'd need to tune them to the same frequency. The 115H-1 is a really nice driver, especially when used like in the XPL200A but it is what it is. It just doesn't like a whole lot of volume behind it and that negates using a larger port.

The best ported system using the 115H-1 was, hands down, the XPL90A. Several members here have them so they could give you the dimensions if they were so inclined. If you know a good cabinet maker, have them build you a pair.

You might even bother looking into a little passive radiator. Gordon W might have some ideas about that.

Titanium Dome
09-09-2005, 08:52 AM
You can find information on this topic here:

http://www.allreaders.com/Topics/info_8562.asp









Okay, okay, don't follow the link with any hope! It's a dumb joke propagated by nerdy English majors.

Sorry. :bs:

analogman
09-09-2005, 08:59 AM
Flared ports would help but you'd need to tune them to the same frequency. The 115H-1 is a really nice driver, especially when used like in the XPL200A but it is what it is. It just doesn't like a whole lot of volume behind it and that negates using a larger port.

The best ported system using the 115H-1 was, hands down, the XPL90A. Several members here have them so they could give you the dimensions if they were so inclined. If you know a good cabinet maker, have them build you a pair.

You might even bother looking into a little passive radiator. Gordon W might have some ideas about that.


Thank you for the reponse. I am seeking suggestions for any ideas/thoughts on improving or reducing the problem, not a re-invention. Also if this were a common issue, or just possibly the funky old receiver. Thanks again for your time!
Regards,
Analogman

analogman
09-09-2005, 09:06 AM
You can find information on this topic here:

http://www.allreaders.com/Topics/info_8562.asp









Okay, okay, don't follow the link with any hope! It's a dumb joke propagated by nerdy English majors.

Sorry. :bs:



:) :bouncy: :)
No need to say sorry, my Mother was an English professor, just not so silly!

Good one :applaud:


As always,
Analogman

Don C
09-09-2005, 09:16 AM
I have never noticed any port noise on my L20ts, and I do play them loud sometimes. Do you turn up the bass control on the amp? Loudness compensation? I use a subwoofer with mine, but the mains are still driven full range.

Lancer
09-09-2005, 09:21 AM
Thank you for the reponse. I am seeking suggestions for any ideas/thoughts on improving or reducing the problem, not a re-invention. Also if this were a common issue, or just possibly the funky old receiver. Thanks again for your time!
Regards,
AnalogmanTurn the volume down then. The ports on the 18Ti, L20t, L20t3, and 4406 will chuff when you drive them hard. Like I said, try a flared port and tune it to match the stock tuning frequency.

The reinvention was a bonus thrown in by me, at my discretion, for those who want to do it. There's always someone out there willing to do whatever.

As for the funky old receiver, sansewage has never been on the list of good power sources.

There... that should brighten up this thread a bit. :rotfl:

stevem
09-09-2005, 03:31 PM
You can find information on this topic here:

http://www.allreaders.com/Topics/info_8562.asp









Okay, okay, don't follow the link with any hope! It's a dumb joke propagated by nerdy English majors.

Sorry. http://audioheritage.csdco.com/vbulletin/images/smilies/bs.gif


I was thinking exactly the same thing! Scary!:rotfl:

analogman
09-13-2005, 11:35 AM
Turn the volume down then. The ports on the 18Ti, L20t, L20t3, and 4406 will chuff when you drive them hard. Like I said, try a flared port and tune it to match the stock tuning frequency.

The reinvention was a bonus thrown in by me, at my discretion, for those who want to do it. There's always someone out there willing to do whatever.

As for the funky old receiver, sansewage has never been on the list of good power sources.

There... that should brighten up this thread a bit. :rotfl:



I thanked you for your suggestions, the most meaningful being flared ports, the least, having a cabinet maker build new cabs for a $100.00 worth of drivers.
I was seeking general information as I am an admitted NOVICE, and meant no disrespect.
Read for meaning, and:

Don't be so God damned sensitive.

Thanks again,
Analogman

analogman
09-13-2005, 11:41 AM
I have never noticed any port noise on my L20ts, and I do play them loud sometimes. Do you turn up the bass control on the amp? Loudness compensation? I use a subwoofer with mine, but the mains are still driven full range.


Don C,
This was with everything "flat" if not trimmed back a bit. It has only happened with this one disc and old receiver combination. Try this recording for a real bass workout, Chet Atkins "Almost Alone", track one "Big Foot". Nice record.
Thanks,
Analogman