Electrovoice Interface D Speakers

[avguytx]

I wish I could come across an EQ for my Interface C's just to see what type of difference it would make. My C's have the "baby cheeks" tweeter....the ST350 I think it is? It's the same one as the D's.

 

[KentTeffeteller]

Hi,

One big reason why Sentrys were sold singly. The EV Sentry line were commonly used in broadcasting stations as control room monitors. The Sentry IV speaker wasn't too common since many stations were using JBL 4311's a lot as well as various AR, Advent, and other such bookshelf speakers for the job. The rarest EV Sentry is the Sentry V (it also is an active monitor). One of the Interface EQ units pictured was made in Newport, TN (I live about 80 miles from there. EV also had a plant in Sevierville, TN also. These plants were shuttered when EV was purchased by Telex).

 

[timl15]

Acoustic foam replacement for base

If you need to replace the base foam on your EV Interface D or Sentry VI speakers, you can get very good replacement ones from here;

http://www.foamorder.com/acoustic.html#customshapes

You can get them to custom cut what you need, for the D's and VI's you need 48" width, 3" depth, and .5" or .75" thickness.

Repaint the base with flat back paint, put these replacement foams in, and your EV speakers will look like new again.

 

[totem]

The series D, V and VI are closely related to the Sentry III,s in lineage
basic design theory, and in some areas the same parts used.

The EQ for the Sentry III is also the SEQ model.

My next on the list task is to run the III,s active and see what the results are.

 

[Michael-Otto]

All ELECTRO-VOICE Home Equalizers called SEQ.

The only important difference in the electronic are 4 Resistors for the different types of ELECTRO-VOICE Speakers.

Michael-Otto

 

[DaWoofer]

Nice info Michael, thanks.

 

[Michael-Otto]

Here are the types of ELECTRO-VOICE Equalizers I know:

Pic XX-11 Two versions, for Interface A (Interface A) & Sentry III (SEQ III)
Pic XX-12 Five Versions, for Interface Alpha (A), Beta (B), Gamma (G),
Delta (D) & Sentry III
Pic XX-13 Luxory 19" Version
PEQ-19 for Sentry III
EQ-19 Four Versions for Interface Alpha, Beta, Gamma & Delta

Modified Versions of all for Sentrv V, TL-303, TL-405, TL-606 & TL-806 and others.

Pic XX-14 & 15 For all Interface D fans, a review from High Fidelity/1978.

Michael-Otto

Sentry 30, Sentry 40, Sentry III (4-way with DH-1506, Interface D VMR, Corona Plasma)
& Interface G.

 

[Vitopanch]

I have two pair of Interface A's, one of which I just obtained NIB. Heh, pretty exciting. Fantastic loudspeakers.

Vito

 

[gonzothegreat]

Sunday afternoon I was reading a book called "Enhanced Sound" by Richard Kaufman and found an article that caught my eye. There was a short bit about Thiele/Small sixth order vented boxes with active equalization <to extend bass response>. While EV didn't call the Interface line by that name in their ads, the details sure sounded similar (6dB of boost at the speaker's resonant freq to extend bass response). More importantly, the article included a schematic for the bass EQ that used TL072 opamps and the formulas to tweak the EQ to the required frequency. The schematic didn't include a sharp cutoff 28Hz filter as the original EQ did but a simple 2nd or 3rd order cutoff should work.

 

[gonzothegreat]

SEQ resistor table

A while back on ebay a seller posted this pic of an EV schematic for the SEQ. Unfortunately the schem isn't complete but the table is. From the schematic it looks like R8/R10 affect the left channel and R24/R26 affect the right channel.

I'll see if I can dig up my two EQs and report back with their values. Once we have a table for all the various models, converting between them should be a snap.

 

[wualta]

Yes, the E-V Interface line were all 6th-order Butterworth alignment speakers that required bass EQ to sound right. Ray Newman was behind their design, as I recall. So was D.B. Keele Jr. Very advanced for their day.

 

[lbrugman]

SEQ Equalizer Schematic

A while back on ebay a seller posted this pic of an EV schematic for the SEQ. Unfortunately the schem isn't complete but the table is. From the schematic it looks like R8/R10 affect the left channel and R24/R26 affect the right channel.

I'll see if I can dig up my two EQs and report back with their values. Once we have a table for all the various models, converting between them should be a snap.

Any luck with the SEQ schematic for EV Sentry III speakers? I found an EV Interface: A Equalizer, but unsure if I can modify it for my Sentry III speakers.

Thanks.

 

[gonzothegreat]

I never had access to a SEQ - only a B/C and a D. According to earlier posts, they were the same internally so somebody else should be able to help you out.

As for my plans to document the EQ resistors, that fell by the wayside and I'm currently nursing a bad case of shingles aka Herpes Zoster with a heapin' helpin of Percocet and enough eyedrops to fill a bathtub.

 

[lbrugman]

Thanks. I hope you feel better soon.

 

[johno5]

This is an old post but will try my luck anyway.. i have just bought a set of interface d's series 2 speakers.. they are set to be bi wired. i want to use them normally. i noticed that there was talk about how to change them back. i turned the speaker over and saw the nob that the pictures show. and is set to be bi wired. i was given the speakers the eq box, amps, external crossover, pre amp and even the manual but was shocked to find out i need some other type of plug to get them back to a single input operation mode.. can anyone explain to me how to get these working with the internal crossover? do i need to remove the wires from that little plug and rewire it? or perhaps something else? hopefully someone will answer soon

 

[gonzothegreat]

Post pictures of the xover plug on your Ds. Chances are they look very similar to the plugs in post 38 of this thread but with different wire placement. While I can't be 100% sure, I suspect the VI's non-biamp plugs are the same as the D's.

How are the foams on your woofers? If they are original, they definitely need new surrounds.

 

[Coytee]

they are set to be bi wired. i want to use them normally. i noticed that there was talk about how to change them back. i turned the speaker over and saw the nob that the pictures show. and is set to be bi wired. i was given the speakers the eq box, amps, external crossover, pre amp and even the manual but was shocked to find out i need some other type of plug to get them back to a single input operation mode.. can anyone explain to me how to get these working with the internal crossover? do i need to remove the wires from that little plug and rewire it? or perhaps something else? hopefully someone will answer soon

(owner of a pair of D's since 1978)

First... just to be retentive, they are setup to be biamped, not biwired. You would need an active crossover ahead of them if that's their setup right now.

The swap from single amp to biamp is as simple as swapping out that plug on the bottom. I've got my biamp plugs somewhere. I looked at them once and the only real difference is the single amp plug is pinned on hole #1, 5 and the biamp plug is pinned on holes 4, 6

I'm making that up since I don't remember the reality but the point is, all the plug does is change some contacts inside the speaker.

If you do not have those plugs or can't find any (or can't repin the ones you have) I'd bet lunch that you could simply jumper the crossver inside with a couple of wires. Speculation on my part but I'd bet it would work.

Heed Gonzo's comment about the foam. Odds are it's shot and if so, needs replaced. That is one thing that really irked me about these. I've had my D's since 1978 and refoamed them (via EV) a couple times. They don't do that anymore as I understand it. I've had my LaScalas since 1979 and using cloth surrounds, they have never needed refoamed.

Good speakers, you'll like them.

If you indeed have an active crossover for them, why not simply biamp them? You could put a nice tube amp on top and a stout solid state on the bottom.

 

[seek/destroy]

Finally have the equalizer in my hands.

 

[johno5]

Thanks for the reply's .. i forgot to check back to see if anyone had replied.. anyway i know about the plug on the bottom of the D's NOW.... after asking stupid questions i decided to do a search and see what other people had to say about them.. I just want to hear these amazing speakers without having to run two amps plus external crossover and such.. I hadn't had these speakers a week and took to get the whole lot checked over, and yes the 12's needed refoaming the rest was ok, except for the foam around the base which i have replaced.. You are right Coytee they sound great, but with the wife threatening divorce the less speakers and amps around the house the better or i might have to sell some, not these ones thats for sure.. anyway, i have been trying to track down a new set of plugs and cant find them so am going to shoot of an email to ev australia and perhaps they can help.. trying to find a 9 pin plug to suit these is turning out to be a hastle.. but worth it they sound excellent as they are, it's just curiosity i guess.. thanks people for your help and kind words

 

[johno5]

Just a quick update for everyone, i have now connected my D's with a hafler 500 amp and perreaux power amp with a ev/ tapco external crossover, and dam do they sound good now, i still havn't connected the d's eq box as i lent it to a friend with a set of C's and he has not returned it yet but have noticed a rather large responce difference between having them bi-amped and not, i do wish to try these speakers with the eq soon.. dam friends.. other than that i have been enjoying these interface d's for quite a while now and i have still not changed my mind, they are still the best speakers i have ever owned..