Hi Forum,
The following project is described in a different forum, less used by DIY audio fanatics.
(for the whole story with more detail look at Audiokarma.com
The last 9 months I have been working on what started as an Electro Voice Interface D revamp into a big project with a full range 5.1 set based on the Interface D design with 6 more speakers in the make to end up with a Dolby Atmos compatible 7.1.4 system.
It al; started when I ran into a nice set of two EV VMR and two EV ST350b speakers and suddenly images from my youth popped up. I have been an Electro Voice fan since my teens end 70's and have actually build a copy of the Sentry III in that time frame. The Interface D was lost in the dungeons of my brain ready to pop up after seeing the VMR.
I have the luck that my nephew has a great wood shop with CNC machines that was owned by his father (my uncle) and his father (my grandfather), so building speakers has been a passion for over 35 years and I have build many models in the HiFi and PA space.
I am not an absolute vintage geek, love those old designs but I don't need to actually recreate the original. I do want a good sonic reproduction of the design so I am looking for the original stuff.
What I want to change is the geometry of the enclosure. I want to give it a slightly more modern appearance but still remain truthful to the original design. This means that I want to make the unit the same height but a more shallow front panel but deeper. This will give a width of about 15" with a depth of 22" with the original height of 32". (this is actually the enclosure 90 degrees turned). I don't want the passive crossover in the open on the bezel, but keep that clean.
The advantage is a nice speaker to look at in the living room (higher WAF) with a better dispersion as there will be less interference from the front panel.
Volume will remain the same so the LF properties will remain unaltered. I need to find a 12" speaker that will be up to the task (thinking on a Sentry 500 driver).
In the early months of this project I mainly focused on the filter and an alternative for the woofer. Until after a few moths I ran into an original (Swiss made) Electro Voice Interface Delta. And through a business relation I got the original Interface D/Sentry VI design with all the mechanical details and filter schematic.
The project got boosted.
I found some extra information about the different VMR's?
There are 4 versions with a 2,5" voice coil, and there is the 2" VC VMR II used in the interface C, The Interface Gamma and the Interface 300 (the last one I had bought was a bad investment as one tweeter was defect one VMR was defect and the woofers were crap)
1803-9864 – This is the hi-fi version from the Sentry VI and Interface D
1803-9943 – This is the original pro version with a voice coil made from round wire. The repair manual says to rebuilt using the voice coil from the 18030595 below.
1803-0037 – This is the same pro version as the 18039943, except that the part number for the plastic ring was different. My suspicion is that this is the white ring stating VMR you see in some pro cabs.
1803-0595 – This is the later pro version with higher power handling with a voice coil made from rectangular wire. As near as I can tell, this coil has the same impedance and performance as the round wire coil from 18039943 and 18030037, except that it has higher power capability.
What this exactly means with respect to the sound is not clear. They are all quite similar but will most likely be different one way or another.
The Interface Delda's arrived:
The foam surround of the 12"down firing woofer was close to being powder. It has been refoamed and the units are playing again.
The enclosure is in an OK shape, but not good enough to be allowed in the living room (no, not my wife, myself)
The plan is to redo the filter by using all air inductors and high quality Mundorf polypropylene caps. This should make the unit sound better and if good enough I will rebuild the enclosure to a less wide but deeper and taller (same volume) shape bringing the tweeter in a better position.
.........Things are getting out of hand …. (that is not new for me ….)
The design of the Interface E is getting more and more shape.
The filter parts are ordered for a full rebuilt of the passive filter with all Mundorf high end caps and air conductors.
The STR350’s are all within a very decent range equal to each other. Very consistent behavior I have to conclude.
I also had some time to listen to the speakers. I used a fairly low cost 45W Denon integrated amp and a budget DVD player as a CD source. Anything but High End and just setup in the office where I performed the measurements as can be seen from the pictures in the attached PDF.
But wow …… the Interface is a very special speaker. I love it now it is rebuild and connected to a slightly better source and amp. The dynamics are awesome; the highs are clean and very honest. Voices are pure, and extremely honest as well. But the power and unlimited dynamics is what struck me most even with this modest amp. Up till now High End audio (and I had some really awesome speakers like the Avalon Eidolon) can be great transparent and with awesome soundstage but sound compressed and canned compared to the “D”. People on other forums raved about these speakers and they are all right.
Jumping to September 2014.
The 5.1 set is done, it performs very well..... see attached pictures
The following project is described in a different forum, less used by DIY audio fanatics.
(for the whole story with more detail look at Audiokarma.com
The last 9 months I have been working on what started as an Electro Voice Interface D revamp into a big project with a full range 5.1 set based on the Interface D design with 6 more speakers in the make to end up with a Dolby Atmos compatible 7.1.4 system.
It al; started when I ran into a nice set of two EV VMR and two EV ST350b speakers and suddenly images from my youth popped up. I have been an Electro Voice fan since my teens end 70's and have actually build a copy of the Sentry III in that time frame. The Interface D was lost in the dungeons of my brain ready to pop up after seeing the VMR.
I have the luck that my nephew has a great wood shop with CNC machines that was owned by his father (my uncle) and his father (my grandfather), so building speakers has been a passion for over 35 years and I have build many models in the HiFi and PA space.
I am not an absolute vintage geek, love those old designs but I don't need to actually recreate the original. I do want a good sonic reproduction of the design so I am looking for the original stuff.
What I want to change is the geometry of the enclosure. I want to give it a slightly more modern appearance but still remain truthful to the original design. This means that I want to make the unit the same height but a more shallow front panel but deeper. This will give a width of about 15" with a depth of 22" with the original height of 32". (this is actually the enclosure 90 degrees turned). I don't want the passive crossover in the open on the bezel, but keep that clean.
The advantage is a nice speaker to look at in the living room (higher WAF) with a better dispersion as there will be less interference from the front panel.
Volume will remain the same so the LF properties will remain unaltered. I need to find a 12" speaker that will be up to the task (thinking on a Sentry 500 driver).
In the early months of this project I mainly focused on the filter and an alternative for the woofer. Until after a few moths I ran into an original (Swiss made) Electro Voice Interface Delta. And through a business relation I got the original Interface D/Sentry VI design with all the mechanical details and filter schematic.
The project got boosted.
I found some extra information about the different VMR's?
There are 4 versions with a 2,5" voice coil, and there is the 2" VC VMR II used in the interface C, The Interface Gamma and the Interface 300 (the last one I had bought was a bad investment as one tweeter was defect one VMR was defect and the woofers were crap)
1803-9864 – This is the hi-fi version from the Sentry VI and Interface D
1803-9943 – This is the original pro version with a voice coil made from round wire. The repair manual says to rebuilt using the voice coil from the 18030595 below.
1803-0037 – This is the same pro version as the 18039943, except that the part number for the plastic ring was different. My suspicion is that this is the white ring stating VMR you see in some pro cabs.
1803-0595 – This is the later pro version with higher power handling with a voice coil made from rectangular wire. As near as I can tell, this coil has the same impedance and performance as the round wire coil from 18039943 and 18030037, except that it has higher power capability.
What this exactly means with respect to the sound is not clear. They are all quite similar but will most likely be different one way or another.
The Interface Delda's arrived:
The foam surround of the 12"down firing woofer was close to being powder. It has been refoamed and the units are playing again.
The enclosure is in an OK shape, but not good enough to be allowed in the living room (no, not my wife, myself)
The plan is to redo the filter by using all air inductors and high quality Mundorf polypropylene caps. This should make the unit sound better and if good enough I will rebuild the enclosure to a less wide but deeper and taller (same volume) shape bringing the tweeter in a better position.
.........Things are getting out of hand …. (that is not new for me ….)
The design of the Interface E is getting more and more shape.
The filter parts are ordered for a full rebuilt of the passive filter with all Mundorf high end caps and air conductors.
The STR350’s are all within a very decent range equal to each other. Very consistent behavior I have to conclude.
I also had some time to listen to the speakers. I used a fairly low cost 45W Denon integrated amp and a budget DVD player as a CD source. Anything but High End and just setup in the office where I performed the measurements as can be seen from the pictures in the attached PDF.
But wow …… the Interface is a very special speaker. I love it now it is rebuild and connected to a slightly better source and amp. The dynamics are awesome; the highs are clean and very honest. Voices are pure, and extremely honest as well. But the power and unlimited dynamics is what struck me most even with this modest amp. Up till now High End audio (and I had some really awesome speakers like the Avalon Eidolon) can be great transparent and with awesome soundstage but sound compressed and canned compared to the “D”. People on other forums raved about these speakers and they are all right.
Jumping to September 2014.
The 5.1 set is done, it performs very well..... see attached pictures
Attachments
Last edited:
Some specs:
Interface Front 111 liter, 22mm MDF + 2x 4mm Lead bitumen - original Interface D speaker units with a new built filter.
Interface surround 52 liter, ST350b, VMR, Eminence Deltalite II 2510.
Interface Center 22 liter, ST350b, VMR, Eminence Deltalite II 2510
Some more pics
Interface Front 111 liter, 22mm MDF + 2x 4mm Lead bitumen - original Interface D speaker units with a new built filter.
Interface surround 52 liter, ST350b, VMR, Eminence Deltalite II 2510.
Interface Center 22 liter, ST350b, VMR, Eminence Deltalite II 2510
Some more pics
Attachments
Mate,
WOW - what a great job. Well done.
I have some Interface C's that have to be rebuilt. The C's sound great as they are even without the eq (it has an issue so not useable currently).
My plan was to find some D's for front end / main duty and the C's for the rear fill, but your little project has me thinking...
Again well done they look fantastic.
Robb
WOW - what a great job. Well done.
I have some Interface C's that have to be rebuilt. The C's sound great as they are even without the eq (it has an issue so not useable currently).
My plan was to find some D's for front end / main duty and the C's for the rear fill, but your little project has me thinking...
Again well done they look fantastic.
Robb
Wow
I consider myself a perfectionist, but I'm rethinking my standard after seeing this. Incredible.
I consider myself a perfectionist, but I'm rethinking my standard after seeing this. Incredible.
Hello everyone from Italy, (translated for our new friend Luca)
I finally managed to get hold of a pair of Interface Delta, the owner just redone the woofer foam, I don't have his equalizer but I bought one in the UK which I will modify as soon as it arrives (resistors and capacitors).
Despite having read most of the discussions on these great speakers I still have a lot of confusion and would like to ask for help.
I would like to make a summary of the crossover capacitors and if possible I would like to have a precise list of those to be replaced, quantity, type, values.
I would also like a clarification regarding the second door of the reflex do I have to open it only if I use its equalizer or can I open it anyway?
Benefits and contraindications?
Sometimes it seems to me that in the musical message the woofer is a bit 'unglued' from the center I think this is perhaps due to the type of loading of the woofer positioned under the speaker, there are by chance some changes that can be made on the crossover to this what to say? I'd also like to make the st350s a little brighter, at the moment I'm used to a pair of Zingali 9010s that have JBL 2405 tweeters.
I thank anyone who can give me the requested information.
Good music
I finally managed to get hold of a pair of Interface Delta, the owner just redone the woofer foam, I don't have his equalizer but I bought one in the UK which I will modify as soon as it arrives (resistors and capacitors).
Despite having read most of the discussions on these great speakers I still have a lot of confusion and would like to ask for help.
I would like to make a summary of the crossover capacitors and if possible I would like to have a precise list of those to be replaced, quantity, type, values.
I would also like a clarification regarding the second door of the reflex do I have to open it only if I use its equalizer or can I open it anyway?
Benefits and contraindications?
Sometimes it seems to me that in the musical message the woofer is a bit 'unglued' from the center I think this is perhaps due to the type of loading of the woofer positioned under the speaker, there are by chance some changes that can be made on the crossover to this what to say? I'd also like to make the st350s a little brighter, at the moment I'm used to a pair of Zingali 9010s that have JBL 2405 tweeters.
I thank anyone who can give me the requested information.
Good music