I read years ago that speech processors like pre-emphasized audio (louder highs, quieter lows). And the heavier the processing the more pre-emphasis is optimum. Does anyone know if the K3 speech processor does that automatically?
Al N1AL On Thu, 2008-02-14 at 01:52, Brendan Minish wrote: > On Wed, 2008-02-13 at 12:12 -0800, Ron D'Eau Claire wrote: > > > There were some microphones produced for the "communications" market back > > then such as the famous Astatic D-104 which had a microphone element with a > > shaped response showing a distinct hump around 3 kHz, rolling off slowly at > > lower frequencies and somewhat faster at higher frequencies. That hump > > helped with "articulation" by emphasizing the mid-range speech frequencies. > > This is a presence peak. > > > I don't know if anyone is doing that today for mainstream communications > > microphones. > > Today Paging Microphones are still specifically designed to have this > pronounced mid range presence peak and also usually include Quite a bit > of low frequency Roll off > > Shure have a range of dynamic elements available for this market, that > have response curves that look remarkably similar to the HC4 and HC5 > elements. > take a look at the response curve of the Shure 450 > http://www.shure.com/ProAudio/Products/WiredMicrophones/us_pro_450SeriesII_content > a direct link to just the curve > http://www.shure.com/groups/public/@gms_gmi_web_us/documents/web_resource/site_img_us_rc_450series2_larg.gif > > the 522 has a broader presence peak > http://www.shure.com/ProAudio/Products/WiredMicrophones/us_pro_522_content > Direct to curve > http://www.shure.com/stellent/groups/public/@gms_gmi_web_us/documents/web_resource/site_img_us_rc_522_large.gif > > elements for these mics (and many others) are available at low cost as > replacement parts. > > Heil sound plot their curves on a different log scale but after > accounting for that the similarities are remarkable. > http://www.heilsound.com/amateur/products/hc4/index.htm > > > The needs of paging systems which include efficient use of limited power > and maximum intelligibility in noisy environments are pretty much > identical to our requirements for effective SSB modulation. Any well > made paging/ Dispatch mic (or element..) is ideal for amateur radio use, > most are far more durable and cost effective than 'the made for ham > radio' stuff that is popular these days. > > > Even the "high end" Ham mics only offer general and > > uninformative comments about "shaping" and "clarity" that say much and > > convey little. > > These words (in ham radio use anyway) have become marketing speak and > now mean nothing. As a former audio professional I cannot understand why > all the hype about Audio in ham radio and to my ears there's a lot of > money wasted on trying to make SSB into something it isn't. > > > Interestingly, one of the big exceptions is the inexpensive > > little Radio Shack electret element. It comes with a frequency response > > chart showing a very flat response across the audio spectrum. > > If you are looking for flat then these are a great place to start, > however the design of the housing may have quite an impact on how things > sound, this can be used to your advantage to create a presence peak or > LF roll off. > > My own headset is based on a salvaged electret condenser mic with some > audio tailoring done by means of a simple R/C filter, being lazy I > copied the circuit of an Icom handmic. It works great and cost me almost > nothing. > > 73's Brendan EI6IZ _______________________________________________ Elecraft mailing list Post to: [email protected] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
