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latestyle
07-16-2009, 12:18 PM
Hi, has anyone taken T-S Parameter measurements of 604Es? I was wondering if one needs to measure TSP for his own set of speakers, or if the variance in TSP measurements among different 604Es is negligible enough that I can use the common measurement when I eventually decide to DIY 604E cabinets... for example, are the TSP data on the following link reliable???

http://alteclansingunofficial.nlenet.net/Thiele-Small.html

Asking because of laziness... don't want to go through the lengths of buying a sine-wave generator, frequency counter, etc.:)

Earl K
07-16-2009, 04:42 PM
Asking because of laziness... don't want to go through the lengths of buying a sine-wave generator, frequency counter, etc.:)
http://www.audioheritage.org/vbulletin/images/statusicon/user_offline.gif http://www.audioheritage.org/vbulletin/images/buttons/report.gif (http://www.audioheritage.org/vbulletin/report.php?p=259486)


- Well, you're in luck because dogmatically using TS parameters doesn't really help one ( arrive at an obvious choice ) when tuning this class of woofer / assuming you follow standard "tuning" guidelines and choose an alignment number [ Q(tc) ] of .5 or greater / .
- With a system alignment like this ( Qtc = .5 or greater ) one will end up with a box size that's too small for producing much bass .

- You'll need to ask around some ( including Todds' Altec Forum over at Hostboard (http://www.hostboard.com/forums/altec-users-board/)) as well as searching all the available forums to find out which box size ( & tuning ) works best for the 604E .
- See if you can engage GM in conversation to ask him if the 604E is a candidate for one of his MLTL tunings ( Mass Loaded Transmission Lines ) .

- If this is all too much hassle / you might just sell them .

>< cheers :)

latestyle
07-16-2009, 08:19 PM
Thanks, Earl... what's strange is that almost everyone that I know (one of them, a very well known speaker designer) has recommended TSP measurements for the 604E & this is the first instance when someone's told me it doesn't matter... hmm...

Earl K
07-17-2009, 06:19 AM
- Here are two system alignments, as generated by my old MacSpeakerz box tuning software ( using the published TS parameters from Todd ) .
- The first system alignment has a Qtc of .5 while the second has a Qtc of .342
- ( ie; it's a small box > then a much larger box / or / 3.2 cu' vs 9 cu' , both tuned to 30 hz ) .

>< cheers :)

latestyle
07-17-2009, 08:43 AM
Earl, thank you so much!