PeterSchut
Active Member
Sorry, I didn't get a message of this reply.
A photo of the woofer from the outside will help, but if you remove the bottom plate you can probably make a phot of the inside trough the fairly large port
Another Electro Voice Interface D/Sentry VI thread.
- Thread starter PeterSchut
- Start date
Sorry, I didn't get a message of this reply.
A photo of the woofer from the outside will help, but if you remove the bottom plate you can probably make a phot of the inside trough the fairly large port
Khaefeli
New Member
Attachments
PeterSchut
Active Member
Hi Khaefeli,
This is not enough but it looks like an Eminence.
If you remove the bottom plate and stick your phone trough the port and make a photo of the rear of the unit we can be sure.
Cheers
This is not enough but it looks like an Eminence.
If you remove the bottom plate and stick your phone trough the port and make a photo of the rear of the unit we can be sure.
Cheers
Khaefeli
New Member
Hi PeterSchut
Thanks for the answer. I'll send you the pictures as soon as I get round to remove the bottom plate.
Do you know what could be the problem that one spekers vmr is playing 3db less louder?
As I'm thinking about buying a new amp I wanted to ask what amp you are using or if you have any special advices.
Cheers
Thanks for the answer. I'll send you the pictures as soon as I get round to remove the bottom plate.
Do you know what could be the problem that one spekers vmr is playing 3db less louder?
As I'm thinking about buying a new amp I wanted to ask what amp you are using or if you have any special advices.
Cheers
PeterSchut
Active Member
The two settings half space and quarter space actually control the mid/high section.
In quarter space the lf loudness is highest as the speaker gets help from both the floor as the side wall so th VMR/ST350 is not attenuated.
In half space the lf is less loud as the side wall is not present so the VMR/ST350 needs to be attenuated to match the lf
That is what the switch does. I guess one switch is broken.
In quarter space the lf loudness is highest as the speaker gets help from both the floor as the side wall so th VMR/ST350 is not attenuated.
In half space the lf is less loud as the side wall is not present so the VMR/ST350 needs to be attenuated to match the lf
That is what the switch does. I guess one switch is broken.
PeterSchut
Active Member
With respect to an amp, anything will do. You don't need a lot of power as t h e efficiency is great.
I had some great music from an entry level Denon.
If you play really loud I can advise bi-amping as the tweeter is fragile and the lf equaliser will make the amplifier clip early.
In bi-amp mode the second amp will stay clean.
I would also think that a tube amp will do great.
I had some great music from an entry level Denon.
If you play really loud I can advise bi-amping as the tweeter is fragile and the lf equaliser will make the amplifier clip early.
In bi-amp mode the second amp will stay clean.
I would also think that a tube amp will do great.
Khaefeli
New Member
As for the poblem with the environment control I think I'll look for that when I remove the bottom plate to take the pictures of the woofer.
As I know you had to do with the crossover of the d's, I wanted to ask you if it would be good to refresh the crossover or if that wouldn't use anything?
Cheers
As I know you had to do with the crossover of the d's, I wanted to ask you if it would be good to refresh the crossover or if that wouldn't use anything?
Cheers
PeterSchut
Active Member
Upgrading the crossover with more modern components will make the D's better. Remove the inductors with the laminated cores to air inductors (will be big).
Better capacitors help with perceived speed of the design, and the inductors that sit on the lefthand side of the filter board interact with each other as the are too close.
Inductors that are close need to be positioned in 90 deg angles.
I also removed all switches as the half space mode worked great and meant less wires and contacts in the signal path.
Khaefeli
New Member
Do you know how much knowledge do i got to have and how hard is it to do so?
Cheers
PeterSchut
Active Member
The schematic is pretty easy and building a new filter isn't too hard.
But a basic knowledge of electronics and soldering skills are required.
Cheers,
Peter
But a basic knowledge of electronics and soldering skills are required.
Cheers,
Peter
Khaefeli
New Member
Ok thanks
Since holidays are here and I have time, I'm planning to open them.
The main reason is that one vmr6 is playing not as loud as the other one.
I want to look if some connections are wrong, since they were reconed and maybe not correctly connected back again.
Cheers and nice holidays
Since holidays are here and I have time, I'm planning to open them.
The main reason is that one vmr6 is playing not as loud as the other one.
I want to look if some connections are wrong, since they were reconed and maybe not correctly connected back again.
Cheers and nice holidays
elektroboy
New Member
Hello EV Folks!
First of all I would like to send All the Best Chritmas and HNY wishes to all members of this Forum and also All the Best and lot of health to all EV Interface Delta / Sentry IV exemplars left on this Earth to date.
I'm very freshly new in here, unfortunately I've found this forum only yesterday. How could I be so blind!
Having read this 10 pages of entries few months earlier, it would save me lot of my time. Normous time and effort needed to solve my obvious problems when trying to give new life to my EV Interface Deltas.
On the other side, while not having all these precious information from Peter (absolutely great, great job done must admit), I've been forced to do my own deep examination of such a amazing piece of ultra-fi sound projectors, as EV Deltas certainly are.
At the end it gave me the enormous knowledge about my speakers and it's very unique construction. Certainly not as deep as Peter's insight, but at least allowing me to read and understand all details written here without any additional questions or digging the net.
I must also admit that 99.9% of the Peter's saying is in line with my own observation and experience.
I seen the most of issues with Deltas are already well covered in here, some of them still might need some attention od additional information. I hope I can help with my own advises, some material related to the Deltas/Sentry IV not published yet and eventually some details of my own way to get sound nirvana from speakers. Naturally I can share some pictures I've done during my countless approach during Deltas restoration.
So here's one of my babies, sitting in my flat in Warszawa. Just right after arrival from Munchen/Germany where I've obtain it some 2-3 months ago. Obviously these are Swiss made Deltas.
woofers right after removal
and then after refoaming
plus few more early pictures
new CMC terminals fits perfectly in the place of the original ones
First of all I would like to send All the Best Chritmas and HNY wishes to all members of this Forum and also All the Best and lot of health to all EV Interface Delta / Sentry IV exemplars left on this Earth to date.
I'm very freshly new in here, unfortunately I've found this forum only yesterday. How could I be so blind!
Having read this 10 pages of entries few months earlier, it would save me lot of my time. Normous time and effort needed to solve my obvious problems when trying to give new life to my EV Interface Deltas.
On the other side, while not having all these precious information from Peter (absolutely great, great job done must admit), I've been forced to do my own deep examination of such a amazing piece of ultra-fi sound projectors, as EV Deltas certainly are.
At the end it gave me the enormous knowledge about my speakers and it's very unique construction. Certainly not as deep as Peter's insight, but at least allowing me to read and understand all details written here without any additional questions or digging the net.
I must also admit that 99.9% of the Peter's saying is in line with my own observation and experience.
I seen the most of issues with Deltas are already well covered in here, some of them still might need some attention od additional information. I hope I can help with my own advises, some material related to the Deltas/Sentry IV not published yet and eventually some details of my own way to get sound nirvana from speakers. Naturally I can share some pictures I've done during my countless approach during Deltas restoration.
So here's one of my babies, sitting in my flat in Warszawa. Just right after arrival from Munchen/Germany where I've obtain it some 2-3 months ago. Obviously these are Swiss made Deltas.
woofers right after removal
and then after refoaming
plus few more early pictures
new CMC terminals fits perfectly in the place of the original ones
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elektroboy
New Member
Here's the scan of the original schematic drawings. Both versions. for earlier Deltas/Sentry IV made before middle 1980 and different one for these made after that date. As can be seen, main difference of newer design is missing smoothing 2.5ohm resistor on woofer (different woofer???). I've tried my Deltas without that resistor and it doesn't worked properly.
Bass is amazing only with this smoothing resistor, exactly as can be seen in Peter's graphs.
In newer scheme there's also few less important changes like different coil value 0,32mH (vs. 0.42mH), possibly due to "updated" ST350B tweeter.
This newer "B" version got cheaper ferrit magnets versus better more expensive AlNiCo magnets used in the earlier ST350A. I'm very happy with the older AlNiCo versions
Also HPF element's values for VRM6 has changed in the newer schematic after june 1980. 15uF instead 17.7uF and 4.0mH vs 4.3mH are the newer values.
Here I've found slight inconsistence in my Deltas.
Despite of having earlier version of Deltas, my VMR crossover's using newer 4mH coils from the newer scheme (should be 4.3mH according to old scheme).
Despite of amazing constructor's job, I have the feeling the production itself was far far away from being ideal.
Although my exemplars are carrying "side by side" serial numbers 30276 and 30277 and I haven't noticed any service activities, there was too many different components
coming from the factory. For example 9uF from LPF of VRS, consists of 2x4.5uF. In both boxes were the same TI type/producent capacitors. So far so good.
But!!! In one Delta was the silver version with alu case marked as Made in Germany and in the second box found same type of capacitors black plastic case "Made in Mexico"!
12" woofers look like there are coming from different production batches.
Vented VMR are also different ones. Both are original HiFi versions (8,8ohm and 9,2ohm coil resistances). One of them has relatively hard suspension (surround), I assume like normally should do. But second has very soft surround and therefore completerly different resonance points and sound is partially different too.
That's very strange for me to me to see this exactly same thind happened by Peter's Deltas! Moreover exactly same strange VMR pair is sitting in the friend's Deltas. One hard, second soft!!! Why the hell is that happening in 3 different Deltas around the Europe?
Well, we could all possibly interchange if... if there is no another problem with the VMR exemplar with soft dumping. There are hearable resonanced coming out of that speaker, once volume is setup slightly louder (let's say from 85-90dB sound pressure).
Most probably this exemplar's suspension need to get similar treatment as Peter's one to get the resonances right. I'm actually managed to purchase one pair EV S15-3 for spare VMR and ST. They are on the way. Once they will arrive will test VMR Pro in my deltas.
Bass is amazing only with this smoothing resistor, exactly as can be seen in Peter's graphs.
In newer scheme there's also few less important changes like different coil value 0,32mH (vs. 0.42mH), possibly due to "updated" ST350B tweeter.
This newer "B" version got cheaper ferrit magnets versus better more expensive AlNiCo magnets used in the earlier ST350A. I'm very happy with the older AlNiCo versions
Also HPF element's values for VRM6 has changed in the newer schematic after june 1980. 15uF instead 17.7uF and 4.0mH vs 4.3mH are the newer values.
Here I've found slight inconsistence in my Deltas.
Despite of having earlier version of Deltas, my VMR crossover's using newer 4mH coils from the newer scheme (should be 4.3mH according to old scheme).
Despite of amazing constructor's job, I have the feeling the production itself was far far away from being ideal.
Although my exemplars are carrying "side by side" serial numbers 30276 and 30277 and I haven't noticed any service activities, there was too many different components
coming from the factory. For example 9uF from LPF of VRS, consists of 2x4.5uF. In both boxes were the same TI type/producent capacitors. So far so good.
But!!! In one Delta was the silver version with alu case marked as Made in Germany and in the second box found same type of capacitors black plastic case "Made in Mexico"!
12" woofers look like there are coming from different production batches.
Vented VMR are also different ones. Both are original HiFi versions (8,8ohm and 9,2ohm coil resistances). One of them has relatively hard suspension (surround), I assume like normally should do. But second has very soft surround and therefore completerly different resonance points and sound is partially different too.
That's very strange for me to me to see this exactly same thind happened by Peter's Deltas! Moreover exactly same strange VMR pair is sitting in the friend's Deltas. One hard, second soft!!! Why the hell is that happening in 3 different Deltas around the Europe?
Well, we could all possibly interchange if... if there is no another problem with the VMR exemplar with soft dumping. There are hearable resonanced coming out of that speaker, once volume is setup slightly louder (let's say from 85-90dB sound pressure).
Most probably this exemplar's suspension need to get similar treatment as Peter's one to get the resonances right. I'm actually managed to purchase one pair EV S15-3 for spare VMR and ST. They are on the way. Once they will arrive will test VMR Pro in my deltas.
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elektroboy
New Member
...forgot to mention, together with Deltas I've also acquired the original Delta EQ.
It seems to be the newer 19" rack mounting capable version.
Once opened, I was quite shocked (negatively) when seeing the completely underrated, inadequate to the class of the equalizer/speaker micro power transformer and extremely low values/small sized filtering capacitors of the equalizer power supply.
Therefore first thing I've done was the significant upgrade of these elements. 50VA toroidal transformer and high quality, higher value than original, filtering caps were inserted to replace old ones.
Despite of that positive change, I'm not advocate for using it yet.
My audio system is almost 100% tube based with lot of air and absolutely incredible, perfect 3D sondscape (I call it my sound hollography).
Moreover Deltas are studio ultra resolution class of speakers pulling the good and bad of the music production to the ears. Truly honest speakers.
And this system clearly revealed to my ears that equalizer in bringing hearable compression, it is "stealing" lot of the air, and negatively affecting big part of 3D holography. In other words minimizing that fragile sens of reality, my speakers and system normally do.
Simply that few more Hz sub-bass extension can't compensate for so many flaws .
Maybe I will return to the idea using it in the biamping setup I'm planning to try once Deltas will be completely done (after VMR issue would be solved).
Then I will be putting equalizer exclusively to the bass channel of biamping . This should minimize negative effect on the rest of the freq. band and extra sub bass may be worth to have. Will see and then share with you.
So it means I'm actually using Deltas in best available single amp setup, 1/2 space mode (boxes are min. one meter from any walls) with both ports open.
I'm actually also using provisional 32cm stands made of empty cabinet of ESS Performance series speakers. Not ideal but cna stand it for a while.
Last but not least here's few pictures of Delta EQ improved power supply.
New versus old transformer and caps. Old transformer look like bad joke! And main filter 100uF as well...
New transformer is inserted prepared to be firmly fixed in the while.
New capacitors are already solderd, old ones left in picture for comparison.
It seems to be the newer 19" rack mounting capable version.
Once opened, I was quite shocked (negatively) when seeing the completely underrated, inadequate to the class of the equalizer/speaker micro power transformer and extremely low values/small sized filtering capacitors of the equalizer power supply.
Therefore first thing I've done was the significant upgrade of these elements. 50VA toroidal transformer and high quality, higher value than original, filtering caps were inserted to replace old ones.
Despite of that positive change, I'm not advocate for using it yet.
My audio system is almost 100% tube based with lot of air and absolutely incredible, perfect 3D sondscape (I call it my sound hollography).
Moreover Deltas are studio ultra resolution class of speakers pulling the good and bad of the music production to the ears. Truly honest speakers.
And this system clearly revealed to my ears that equalizer in bringing hearable compression, it is "stealing" lot of the air, and negatively affecting big part of 3D holography. In other words minimizing that fragile sens of reality, my speakers and system normally do.
Simply that few more Hz sub-bass extension can't compensate for so many flaws .
Maybe I will return to the idea using it in the biamping setup I'm planning to try once Deltas will be completely done (after VMR issue would be solved).
Then I will be putting equalizer exclusively to the bass channel of biamping . This should minimize negative effect on the rest of the freq. band and extra sub bass may be worth to have. Will see and then share with you.
So it means I'm actually using Deltas in best available single amp setup, 1/2 space mode (boxes are min. one meter from any walls) with both ports open.
I'm actually also using provisional 32cm stands made of empty cabinet of ESS Performance series speakers. Not ideal but cna stand it for a while.
Last but not least here's few pictures of Delta EQ improved power supply.
New versus old transformer and caps. Old transformer look like bad joke! And main filter 100uF as well...
New transformer is inserted prepared to be firmly fixed in the while.
New capacitors are already solderd, old ones left in picture for comparison.
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dc270
Now Off the Reservation
Did I read you correctly- to replace all the inductors with air core types? I would not necessarily agree with this! Unless you are an audio engineer and well versed in insertion losses, various voice coil impedance reactions, etc, etc I would leave the inductors as is. The caps are one thing- but the inductors do not wear or have adverse effect of age as most x-over components do.
One thing I would do however- to prevent possible cross talk is to separate and re-orient the inductors, I.E. lay one flat, the next closest set upright, the next right angle to that, etc, etc,
I would use terminal barrier strips to inter connect with and solder everything into place with good point to point wiring.
Good luck- you have all the makings of a very nice project- EV certainly had the engineers, the components and the name for some very good speakers. I have had several of their models and loved every one-once I got them fully repaired!
DC
One thing I would do however- to prevent possible cross talk is to separate and re-orient the inductors, I.E. lay one flat, the next closest set upright, the next right angle to that, etc, etc,
I would use terminal barrier strips to inter connect with and solder everything into place with good point to point wiring.
Good luck- you have all the makings of a very nice project- EV certainly had the engineers, the components and the name for some very good speakers. I have had several of their models and loved every one-once I got them fully repaired!
DC
elektroboy
New Member
I fully agree with you, I would not touch the original coils, they looks pretty well and they are part of the excellent original sound sound of Deltas/Sentry IV.
I always recommend not to change the winning team.
Despite of temptation to rewire/restrip whole thing, I would also advice to keep all elements of the crossover at it's original places and positions.
We should not forget all these elements (eventually except orientation change of the coils) as they certainly has specific role as diffuser of the woofer's and port's sound output (dispersion)!
Who knows how this would change the sound after making it tidy place? I'm not sure it would be improvement.
Again, it's always worth to keep in mind, whenever wherever possible, stick to winning team.
Naturally I've replaced most of the capacitors except 90uF woofer one (rest has been changed to the excellent russian army PIO ones).
Also like Peter did, I've also eliminated tweeter protection unit, all switches and naturally all thin wires related to them. Radically shortened signal path, free of these old swithces proved to has excelent influence to the improvement of the sound.
Finally I've generally stuck to the 1/2 space scheme, except "delicate" fine tuning of the tweeters L-pad I've done in order to fit my room specifics and my sound preferences. Parallel resistor changed to 12,4ohm (from 18ohm) while resistor in serie with ST350A has changed to excellent Duelund Carbon resistors 3,5ohm 10W (iso ceramic 2,7ohm ones).
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Khaefeli
New Member
Nice Project you got there.
Your discovery with the different vmrs was interresting. I also had the problem that on vmr was playing 4db louder as the other one.
I dont know if its the same reason as with yours because i have also problems with the 1/2 and 1/4 switch in the speaker with the less louder vmr.
As I mentioned a view weeks ago its paying louder when on 1/2 which is actualy the exact opposite of what it should.
Since I was planning to refresh the speakers and repair this problem I wanted to ask how much the Sound improved with all the changes you made?
Cheers
Your discovery with the different vmrs was interresting. I also had the problem that on vmr was playing 4db louder as the other one.
I dont know if its the same reason as with yours because i have also problems with the 1/2 and 1/4 switch in the speaker with the less louder vmr.
As I mentioned a view weeks ago its paying louder when on 1/2 which is actualy the exact opposite of what it should.
Since I was planning to refresh the speakers and repair this problem I wanted to ask how much the Sound improved with all the changes you made?
Cheers
elektroboy
New Member
Naturally I can't be 100% sure what would cause the louder VMR playing in 1/2 space position.
But the first thing I would do is to check the wires.
As I've mentioned, there's too many flops and imperfections in the original factory assembling of EV Deltas. Different capacitors, drivers from different production batches to mention a few.
Therefore I would not be surprised if there are wires connected wrongly to the "1/2-1/4" switch. Or maybe someone made some servicing earlier and connected wires incorrectly. Worth to check.
Secondly you should also check both VMR "L-Pad" resistors.
40ohm/20W resistor, connected parallel and 5ohm/30W connected in serie to the VMR. These are active once 1/2 switch space is activated.
For example if that 40ohm one is burned (has infinity resistance) or 5ohm is shorted (least expectable), in any of those cases VMR would play louder few dB in 1/2 setting.
Once resistors are OK, only wrong connection of the wiores/switch could be reason for VMR playing louder in 1/2space setting. As simple as this.
With regard the sound on my Deltas.
After all "step by step" changes I've done in the last 2 months (matched PIO capacitors implementation, tweeter's L-pad resistors replacement / fine tuming),
elimination of the switches (shortened signal path), tweeter's protection unit and high tones attenuator removal, my Deltas sounds fantastic. Certainly more than one class better that before these changes.
Very hearable, enjoyable, simply significant improvement. Sound is crystal clear (except occasional resonances from one VMR when playing loud - described earlier), very musical, controlled, perfectly ballanced, extremely fast and dynamic. Like sound holography.
And these mids coming from them are second to none!
Possibly the best "all round" of all speakers I've ever heard. I'm not using the equaliser. Sound of Deltas with both ports open is clearly the one i consider as the best and most natural.
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