Posted this under full range which might be the wrong sub forum, so re-posting here.
Hi, looking for some advice. I broke the terminal on my Vifa d25AG35 tweeter and am looking at options for replacing or re configuring my speakers.
My system consists of 2 rather old custom made transmission line units which originally came with KEF b110 woofer and T27 Tweeter. At some point they were rebuilt using a VIFA p13 mid-woofer and the above mentioned D25 (which is no longer available). I also have a pair of 10 inch sub-woofer which I am Bi-amping with a 24db/octive electronic crossover at 90hz (I can also choose 120hz). I’m using a pair of Adcom 5400 amplifiers rated at 125W per channel to drive the speakers.
Looking for options
Should I try and replace my current drivers?
Should I try full range with something like the Markaudio 7MS and eliminating the current passive 2 way crossover.
Should I consider a single drive open baffle design
I’d appreciate some feedback with options, pros and cons, etc.
Thanks, appreciate any help. If you need more info let me know.
Hi, looking for some advice. I broke the terminal on my Vifa d25AG35 tweeter and am looking at options for replacing or re configuring my speakers.
My system consists of 2 rather old custom made transmission line units which originally came with KEF b110 woofer and T27 Tweeter. At some point they were rebuilt using a VIFA p13 mid-woofer and the above mentioned D25 (which is no longer available). I also have a pair of 10 inch sub-woofer which I am Bi-amping with a 24db/octive electronic crossover at 90hz (I can also choose 120hz). I’m using a pair of Adcom 5400 amplifiers rated at 125W per channel to drive the speakers.
Looking for options
Should I try and replace my current drivers?
Should I try full range with something like the Markaudio 7MS and eliminating the current passive 2 way crossover.
Should I consider a single drive open baffle design
I’d appreciate some feedback with options, pros and cons, etc.
Thanks, appreciate any help. If you need more info let me know.
Sounds like a plan, some good tips at Meniscus on Vifa voicecoil repairs:
Vifa D27 Voice Coil - Meniscus Audio
The original metal dome:
https://www.tymphany.com/wp-content/uploads/2018/10/Discontinued-Vifa-Products-D25AG-35-06.pdf
I don't suppose this new $30 Vifa would sound much different:
Tymphany, DA25BG08-06 - Meniscus Audio
Vifa D27 Voice Coil - Meniscus Audio
The original metal dome:
https://www.tymphany.com/wp-content/uploads/2018/10/Discontinued-Vifa-Products-D25AG-35-06.pdf
I don't suppose this new $30 Vifa would sound much different:
Tymphany, DA25BG08-06 - Meniscus Audio
it was Miniscus that suggested the soft dome rebuild. They also suggested the DA25 tweeter, but it would require a larger hole for mounting. Tough decision, but I am leaning towards the rebuild unless someone can give me a compelling reason to go with the Da25.
The terminal is not fixable in my opinion
The terminal is not fixable in my opinion
Only difference I see in mounting the newer metal tweeter is you'd need to file off a bit of timber to accomodate the terminals being diametrically opposed. A work of 5 minutes.
A soft dome has a slightly softer sound. They'll both work. No need to change as a pair. Tiny differences.
I think you could toss a coin on this one.
A soft dome has a slightly softer sound. They'll both work. No need to change as a pair. Tiny differences.
I think you could toss a coin on this one.
You are correct the baffle hole is the same other than the terminals. I miss read the dimensions. I did order 2 voice coils just to be safe. I found the metal cones a little fatiguing so I'm hoping the slightly softer sound will be more enjoyable. Either way I think I'll be satisfied with the results. Appreciate your advice.
Personally I think the silk dome is a better mate for the P-13. I've done a few Frankentweeters using Vifa Parts and I have a set of aluminium domes here in a Frankentweeter if you were interested in them but the domes do have some small wrinkles.
Full tweeters tho not just the butterfly VC
PM me if interested
Full tweeters tho not just the butterfly VC
PM me if interested
I don't know if you like delving into crossovers, but there is a famous design by Mr. Lynn Olson that uses near enough your drivers, so would work:
Ariel Speaker Page
You would convert the bass filter to 2mH, 6,8R and about 5uF for a single midbass and attenuate the tweeter 6dB, Depends if you are happy with what you have. Lynn knows what he is doing, but always felt his design worked best with valves.
Ariel Speaker Page
You would convert the bass filter to 2mH, 6,8R and about 5uF for a single midbass and attenuate the tweeter 6dB, Depends if you are happy with what you have. Lynn knows what he is doing, but always felt his design worked best with valves.
Thank you for the crossover info. It was probably 25 years ago that I replaced the Kef units with the Vifa's. They came with 2 crossover boards each which are externally mounted. I'm going to see if I can still read the values of the components. Hopefully they're not to faded to read. This has reawakening the audio hobby that was dormant for many years.
Here is a crude drawing of my crossovers from what I can see. If you can give any feedback or comments etc I’m all ears. Remember I’ve been out of the game for a long time and have forgotten a lot.
The Low Pass looks like a positive lead to a .85 air core leading to two parallel 10uf capacitors to a 2.49 resister then negative
The High Pass looks like positive to two parallel capacitors (2uf and 4.7uf) then a .47 air core to negative and a 3.01ohm resistor to tweeter positive lead then a 10ohm resistor back to negative.
crossover.pdf - Google Drive
Low pass components are
.85 mh air core
10uf capacitors (2)
2.49 ohm resistor
High pass components
.47mh air core
4.7uf capacitor
2uf capacitor
3.01 ohm resistor
10 ohm resistor
The Low Pass looks like a positive lead to a .85 air core leading to two parallel 10uf capacitors to a 2.49 resister then negative
The High Pass looks like positive to two parallel capacitors (2uf and 4.7uf) then a .47 air core to negative and a 3.01ohm resistor to tweeter positive lead then a 10ohm resistor back to negative.
crossover.pdf - Google Drive
Low pass components are
.85 mh air core
10uf capacitors (2)
2.49 ohm resistor
High pass components
.47mh air core
4.7uf capacitor
2uf capacitor
3.01 ohm resistor
10 ohm resistor
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Hi, I would replace the two caps in line with the tweeter with one 6.8 uF/250V film cap, only if they are effectively in parallel ( if it was C-L-C, i.e. a 3rd order crossover, and not a C-L...).
Also the woofer cap...22uF ( standard, but you may find 20 uF) single capacitor is better than two. In this case you don't need a film cap. I mean, you can go Polypropilene if you don't mind spending 10/20 $ for a cap. 6.8 uF/250 V goes at about 2/3 $ ( phisical store, no boutique brand)
Also the woofer cap...22uF ( standard, but you may find 20 uF) single capacitor is better than two. In this case you don't need a film cap. I mean, you can go Polypropilene if you don't mind spending 10/20 $ for a cap. 6.8 uF/250 V goes at about 2/3 $ ( phisical store, no boutique brand)
Ooooh it should be around 2k5 Hz as usual
Really, IDK!
The slopes....slooooopes....the resistor on the leg of the 20 uF cap suggests a mild action of the cap itself, which means lesser attenuation...err...not so steep as there was no R. It goes together with the damping wanted for the speaker+box, so you might want to change its value ( hint: don't do it!)
Really, IDK!
The slopes....slooooopes....the resistor on the leg of the 20 uF cap suggests a mild action of the cap itself, which means lesser attenuation...err...not so steep as there was no R. It goes together with the damping wanted for the speaker+box, so you might want to change its value ( hint: don't do it!
)An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Not sure if this helps or not
I can't see anything there, my friend. You need to upload images to the forum with the paperclip thing in the reply box.
Here's what your circuit should be. 2kHz crossover, 4dB less bass below 500Hz than Lynn's circuit which is 3kHz crossover. But it works well enough, IMO. If you are happy with the bass, I would leave well alone.
Here's what your circuit should be. 2kHz crossover, 4dB less bass below 500Hz than Lynn's circuit which is 3kHz crossover. But it works well enough, IMO. If you are happy with the bass, I would leave well alone.
Attachments
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Yes, you are correct, my schematic is wrong. It took me a bit to wrap my head around the wiring, put the second 10ohm resister crosses the tweeter + and - . Learning a lot here, very grateful. Looks like I will leave it alone although I may rewire the speakers to the crossover boards to make it neater. New voice coils due next week.
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