Electro Voice Sentry 100A? Studio monitors of the 90s.

[low_art]

https://mypicsonline.net/archive/archives.telex.com/archives/EV/Speakers/EDS/Sentry 100A EDS.pdf

See above, the documentation for Electro-Voice Sentry 100A studio monitors. Looks like a competently designed speaker and one I might have a line on for a reasonable price (in need of new surrounds of course). I'm curious to see what other's opinions are on the information presented above.
Thanks.

 

[Mr. Swordfish]

These were ubiquitous in the 80s and 90s as broadcast studio monitors. Ports in the front and designed to be hung on the wall, so a bit bass shy if you don't. I did a lot of remote recording work with these as monitors with good results. I haven't actually listened to one in a decade or more so don't know what I'd think of them now, but if a pair came my way at a reasonable price I'd probably snag them.

I have a pair of EV Five C speakers that are roughly the same vintage, but designed for home use as opposed to a studio monitor. Acoustic suspension vs. bass reflex and a larger woofer then the 100As so not the same thing. I really really like the way they sound - a bit less detailed than some and missing the bottom octave, but very "musical".

 

[Bruce Morgen]

https://mypicsonline.net/archive/archives.telex.com/archives/EV/Speakers/EDS/Sentry 100A EDS.pdf

See above, the documentation for Electro-Voice Sentry 100A studio monitors. Looks like a competently designed speaker and one I might have a line on for a reasonable price (in need of new surrounds of course). I'm curious to see what other's opinions are on the information presented above.
Thanks.

They will probably need more than the usual woofer surrounds -- the foam "acoustic lens" (in lieu of a proper 21st century wave guide ) around the tweeter also tends to rot away and I'm not sure there's a suitable aftermarket solution for that. The crossover is a typically simple previous-century circuit, with a pretty odd value for the HPF cap for the tweeter -- I'm not sure that's critical, since the level control is going to influence the LCR arithmetic anyway. The schematic and other service info are in the attached PDF. They are rated for only 30 watts max., but the speaker I had with the same woofer -- a 1970s design, btw -- handled my old 55 WPC power amp just fine until the foam gave out, probably due to the relatively high sensitivity not really needing all that much power to play loud.

 

[Mr. Swordfish]

They are rated for only 30 watts max...

Yes, but here's how they arrived at the 30 watt figure:

The 30-watt specification for the Sentry 100A is based on filtered random noise (FM interstation noise and tape hiss are common forms of random noise), which is fed to the speaker for an extended time (more than 15 hours).

IOW, they won't blow up very easily. IIRC, we powered them with a Crown D-60 and never felt like they wouldn't get loud enough.

 

[Bruce Morgen]

Yes, but here's how they arrived at the 30 watt figure:



IOW, they won't blow up very easily. IIRC, we powered them with a Crown D-60 and never felt like they wouldn't get loud enough.

Fair enough -- makes total sense!

 

[low_art]

They will probably need more than the usual woofer surrounds -- the foam "acoustic lens" (in lieu of a proper 21st century wave guide ) around the tweeter also tends to rot away and I'm not sure there's a suitable aftermarket solution for that. The crossover is a typically simple previous-century circuit, with a pretty odd value for the HPF cap for the tweeter -- I'm not sure that's critical, since the level control is going to influence the LCR arithmetic anyway. The schematic and other service info are in the attached PDF. They are rated for only 30 watts max., but the speaker I had with the same woofer -- a 1970s design, btw -- handled my old 55 WPC power amp just fine until the foam gave out, probably due to the relatively high sensitivity not really needing all that much power to play loud.

Thanks for the additional information. I found a thread on Audiokarma about constructing new "lenses" from two different sizes of armaflex pipe insulation - it looks like a reasonable facsimile of the original and I'll give it a shot if I pick up these EVs.

 

[Wolf11Man]

Please take into account these speakers were made to sound great with the source material of their time. This was reduced low and high end response, mostly from record players. In such a setting, the EV speakers sounded dynamic and life like, much better than the average products of the days.
If you feed them with todays material and drive them with modern amps, you mayl be very disapointed. A lot of time has passed... be realistic.
Nothing you can not cure with a DSP, even better, driven through an active x-over or at least with new developed, passive one.