Replacing my tweeters a good idea?


I have a pair of infinity Delta 70 loudspeakers. They have 2x8" 1 6" 1 4" and a metal tweeter. They image superbly, and set a good soundstage. People think infinity are bad, but they are great in my ears, apart from the metal dome tweeter. It gets a bit harsh on some recordings. Is it possible that i could replace the tweeters with something else, say dynaudio tweeters? would it be worht the trouble? I am not getting new speakers.. so dont bother trying to say that. :P thanks
shabbadoo
Trelja...I couldn't have said it better. Bryhifi...I spent two grand on power tools, bought 3 or 4 20 foot sections of PVC water pipe, and built a pretty cool cylindrical 3-way using SEAS 5 mid and 0.75 plastic dome, with Peerless 8 down-firing woofer. I had built a similar cylindrical speaker as a kid using 3 foot clay sewer pipes, mounting a coaxial Jensen or Utah (remember them?) driver upward-firing into a plaster-filled kitchen funnel for 360 dispersion. What a hoot! So I decided to revisit that idea with modern materials. Well, no-one seemed excited about a cylindrical shape, so I never built the second side. Sound was pretty good, although woofer/mid crossover was problematic. Got good at voicing crossovers, and noticed that I could hear 1/3 dB changes over 1.5 octaves in the upper crossover region. After seeing that raw driver sensitivity tolerances are typically +/- 5-10 times that level I quickly realized that it would be impossible to make speaker systems consistently without customizing each crossover, or spending a fortune to get tight-tolerance drivers. I built with others 20 pair of a nice 6.5/1 two-way a few years back that ALMOST got into production as a reinforcement system for a digital piano mnaufacturer. A local high-end dealer liked them A LOT, but we couldn't get the cabinet maker to take a repeat order at a reasonable price. Voicing a matched-pair of speakers is a labor of love, and I have great appreciation for those who do it well. I preferred these two-ways to many commercial designs for a long time, but after I heard what Bruno Pelchat et al at Verity Audio accomplished with their Parsifal Encores, in my living room, my jaw dropped! Had to have 'em! So I'm done...for now. (PS. Want a good deal on Seas 5" 'bullet' dustcap, or those tweeters? How about the Peerless CC line 8"? A nice router...or maybe a belt-sander? Oh well, it was fun. It's all about the process, anyway, right?) Shabbado...you mean "low-pass", and no, that's NOT what you want to do. Room treatment, upstream components, maybe 1-2 ohms on the tweeter: try 'em all, and have fun!
As has been mentioned your speaker system is the sum of it'parts.The drivers,box and crossover values were designed to work as a unit.I contemplated and did exactly what your thinking of doing.I had an average pair of small monitors that became test subjects.I disected the little guys and in the process with alot of other research learned a great deal about what constitutes a good sounding speaker.Trying to replace your tweeters involves alot more than just buying better ones.First off even if you had the specs for your existing pair don't forget that the new ones would not only have to match electrically but physically as well.Finding replacements with the same mounting flange diameter,bolt pattern ect. is the real challenge.If your determined to improve your speakers I'd go with the earlier suggestion of installing better crossover parts and again thats only if you can get a schematic with the exact values of the existing crossover parts.I have had excellent results with this approach.Generally you'll find that the major difference between an average speaker and a great one is the quality of the coils,caps and resistors.
To add to my thoughts above I forgot to mention that the easiest and most cost effective improvement is to replace the existing internal wiring with high quality wire from Cardas,Kimber,XLO ect. The upper frequencies are particularly suseptable to changes in the wire used.
Do you think that my cables/interconnects may be my problem? I have kimber cables running them, the grey and black ones, the 4VS model. Is there any speaker cable that might be better for about the same money? my interconnects are not that flash.. any reccomendations?
I hate to have to say it again, but changing the impedance of the driver ( or the load that the passive crossover sees ) WILL affect crossover frequency. If you don't believe me, try asking on the Madisound board. Calculate the crossover for a 4 ohm driver and then substitute an 8 ohm driver in its place. BAD NEWS, guaranteed. Nothing will work as you expected. That's why most quality speakers use impedance compensated L-pads or factor in the attenuators in the first place. Otherwise the hinge points would change as you varied the level of attenuation by altering the impedance of the circuit. I think that either Parts Express or MCM even covers this with charts for the various impedance drivers in one of their catalogues. Wiring a resistor that matches the tweeters impedance in parallel and then placing one that was rated for half its impedance in series would reduce the output while maintaining the same load / crossover point. Another "side effect / benefit" to doing this would be increased power handling in the high frequency section. Sean >