Electrovoice 8HD Horns

[22frank]

I have some vintage electrovoice mid range horns I am fixing up. I see where EV used alot of drivers. Some were siren!! drivers. Anyway the most noted is the T25 type. Question = some threaded directly with the 1 1/8 inch and some have a bolt on adapter plate. The horn is 8HD. I have loooked in the
Telex archives and dont see anything about this.. Does any one out there every seen this?

 

[radioactive]

you might want to look for a 1823 or 1828 which should bolt on just fine.

 

[Tom Brennan]

you might want to look for a 1823 or 1828 which should bolt on just fine.

Don't confuse the OP RA; those drivers screw on. They have male threads that fit the female threads of the 8HD; the standard 1 3/8-18 threading.

Frank; what you're asking is unclear. Are you asking which EV drivers screw on to the 8HD?

 

[Stephen J]

I personally have never seen a driver with a bolt on adapter connected to an 8HD. The only reason to do so would be to use a driver with a different size throat,presumably larger.
IMO...As the 8HD is not particularly well regarded. ( not even by the engineers that designed it) a larger driver would be a waste.
If you are going to use the 8 HD,T25/T25's,1823/1823M's or 1824M's are usually associated with those horns.
BTW,the 8HD horn was designed to be vertically mounted. :yes:

Ya know...
...I think there was a support bracket that slipped between the driver and horn,and was then connected to a brace that was screwed to the bottom or side of the cabinet,to help support the weight of the driver. Maybe that's what you saw.??..:scratch2:

 

[22frank]

Thanks for the replies. Years back I got a pair of EV aristrocat speakers. $60 for the pair. They came with a 12B woof and a T35B tweet. This was a low priced set, I am up- grading it with the 8HD mid, which already has a cut out for this horn. I have seen many 8
HD horns in
Ebay and I think now what
I see is that bracing bracket for driver support :scratch2:

 

[djnagle]

ANY driver is better than the T25...even by EV's engineers thinking. I have had the 8HD and T25 many times, then just seem to pop up in my life. I always thought the horn was the problem. Not so. I screwed in a pair of Selenium 210s just for kicks and never took them out. That horn is not that bad with a good driver.

 

[Java1960]

ANY driver is better than the T25...even by EV's engineers thinking. I have had the 8HD and T25 many times, then just seem to pop up in my life. I always thought the horn was the problem. Not so. I screwed in a pair of Selenium 210s just for kicks and never took them out. That horn is not that bad with a good driver.

I don't see that driver available as a 16ohm, I was hoping to try that in my Aristocrat since I am missing one T25A anyway.

 

[GordonW]

There's a 16 ohm diaphragm available for the Selenium D220Ti:

https://www.parts-express.com/selenium-rpd220ti-16-diaphragm-for-d220ti-and-d2500ti--264-277

Unfortunately, you apparently can't buy the D220Ti driver with that 16 ohm diaphragm installed- but even buying the 8 ohm normal version and then buying the 16 ohm diaphragm- it's still less expensive than the cheapest other 16 ohm driver I could locate, in a quick search...

Regards,
Gordon.

 

[Java1960]

Thanks Gordon. So you think instead of buying a used T25A at $100 plus I would be better off getting two of the D220Ti and maybe sell my existing single T25A to fund the purchase?

 

[jwrauch]

The 8HD sounds pretty good with the 1828R, 1824M, and 1823M drivers. at least to my ears. It got its bad rep with the crappy T25 A drivers. JOHN

 

[Java1960]

I found a pair of the 1824M at same price as T25A so I ordered them and will probably just sell the single T25A I have. Thanks for the advice

 

[Java1960]

Well the 1824M is 8 Ohm so that may be an issue. Can't seem to find 16 Ohm parts for it either. May need to find other drivers after all

 

[totem]

Well the 1824M is 8 Ohm so that may be an issue.

Excuse my ignorance but is the issue what the amp needs to see or more specifically the resulting sensitivity achieved by the driver
for matching spl's?

 

[Java1960]

I have a pair of Aristocrat III with 12w, T35 and T25A all 16 Ohm with X8 and X36 crossovers. I am missing one T25A but have a pair of 1824M but are 8 Ohms so not sure how good a fit that would be. I have heard of people upgrading to 1824M in this cabinet but they may have been using 8 Ohm drivers. The amp will be fine with anything between 4-16

 

[totem]

Maybe someone can comment further on the issue specifically how it would affect things.

I happen to have a pair of Luxman constant impedance attenuators recommended
for use on mids and highs for level matching on the fly.

 

[jwrauch]

I have a pair of Aristocrat III with 12w, T35 and T25A all 16 Ohm with X8 and X36 crossovers. I am missing one T25A but have a pair of 1824M but are 8 Ohms so not sure how good a fit that would be. I have heard of people upgrading to 1824M in this cabinet but they may have been using 8 Ohm drivers. The amp will be fine with anything between 4-16

Try them and see. It wont hurt anything. JOHN

 

[Notek]

The statement that the 8HD was "not particularly well regarded (not even by the engineers that designed it)" is presented without any evidence from Electro-Voice engineering reports, design notes, or factory literature. [audiokarma.org]

What's interesting is that later in the same thread, other experienced EV users say almost the opposite:

• One member claims the real weak link was the T25A driver, not the horn itself, and reports much better performance with other drivers. [audiokarma.org]
• Another member says the 8HD sounds "pretty good" with 1828R, 1824M, and 1823M drivers and that its bad reputation came from the T25A. [audiokarma.org]

Looking at EV's history, the 8HD was used in a lot of factory systems for years. If EV engineers truly thought it was a fundamentally poor horn, it's hard to explain why it kept appearing in so many commercial and consumer products. That's my opinion, not something explicitly stated in the source.

The one thing in that post that is well known is the vertical-mount recommendation. The 8HD's dispersion pattern was intended around vertical installation, which is why you often see the horn stood upright in EV literature and cabinet layouts. [audiokarma.org]

 

[loudnoises]

The statement that the 8HD was "not particularly well regarded (not even by the engineers that designed it)" is presented without any evidence from Electro-Voice engineering reports, design notes, or factory literature. [audiokarma.org]

What's interesting is that later in the same thread, other experienced EV users say almost the opposite:

• One member claims the real weak link was the T25A driver, not the horn itself, and reports much better performance with other drivers. [audiokarma.org]
• Another member says the 8HD sounds "pretty good" with 1828R, 1824M, and 1823M drivers and that its bad reputation came from the T25A. [audiokarma.org]

Looking at EV's history, the 8HD was used in a lot of factory systems for years. If EV engineers truly thought it was a fundamentally poor horn, it's hard to explain why it kept appearing in so many commercial and consumer products. That's my opinion, not something explicitly stated in the source.

The one thing in that post that is well known is the vertical-mount recommendation. The 8HD's dispersion pattern was intended around vertical installation, which is why you often see the horn stood upright in EV literature and cabinet layouts. [audiokarma.org]

I suspect this may not be an actual person.