Hi guys,
I have new toy to play with - Hales Revelation Three old 3way floorstand loudspeakers. I am based in UK.
The aluminium alloy dome tweeters are Vifa D25AG-35-06, one with dented dome, another one too and pierced a little. Probably someone tried to flatten the dents by using a needle, what a shame.
Amplification is provided by Naim NAC82/HiCap/NAP250 olive series, then 4m Van Damme hifi series 4mm2 speaker cables.
Whatever source I use, the results are similar.
The speakers sound sharp at top end. Other music spectrum is very nice, balanced.
I am not sure this is characteristic feature of these speakers, it's revealing for sure, but sometimes ear piercing, specifically sybilances are too strong.
Is that caused by tweeters damage?
If I will go for these rare tweeters exact replacement, would be that final cure for the sybilances?
I am not sure, thus please whoever can help, help!
I could also try easier to find second hand D25AG-05-06, though not exactly the same tweeter as original.. would be that suitable?
Found possible alternatives - aluminium dome Seas 27TBFC/G H1212 for £36.58 each.
If not alluminium dome, maybe silk dome alternatives would be Vifa Peerless D27TG-35-06 for £26.58 or Seas 27TFFC H0881-06 for £33.17
This is just what I found without knowledge whether they can be used as drop in replacement or not.
I would welcome a little bit softer/ or narrower top end and maybe that can be achieved by some kind of tweeter damping.
I dismantled the huge front baffle and found the crossover underneath is untouched, all original parts, air coils only, AXON capacitors except woofer section and resistors MEXICO and DALE.
Thank you all.
I have new toy to play with - Hales Revelation Three old 3way floorstand loudspeakers. I am based in UK.
The aluminium alloy dome tweeters are Vifa D25AG-35-06, one with dented dome, another one too and pierced a little. Probably someone tried to flatten the dents by using a needle, what a shame.
Amplification is provided by Naim NAC82/HiCap/NAP250 olive series, then 4m Van Damme hifi series 4mm2 speaker cables.
Whatever source I use, the results are similar.
The speakers sound sharp at top end. Other music spectrum is very nice, balanced.
I am not sure this is characteristic feature of these speakers, it's revealing for sure, but sometimes ear piercing, specifically sybilances are too strong.
Is that caused by tweeters damage?
If I will go for these rare tweeters exact replacement, would be that final cure for the sybilances?
I am not sure, thus please whoever can help, help!
I could also try easier to find second hand D25AG-05-06, though not exactly the same tweeter as original.. would be that suitable?
Found possible alternatives - aluminium dome Seas 27TBFC/G H1212 for £36.58 each.
If not alluminium dome, maybe silk dome alternatives would be Vifa Peerless D27TG-35-06 for £26.58 or Seas 27TFFC H0881-06 for £33.17
This is just what I found without knowledge whether they can be used as drop in replacement or not.
I would welcome a little bit softer/ or narrower top end and maybe that can be achieved by some kind of tweeter damping.
I dismantled the huge front baffle and found the crossover underneath is untouched, all original parts, air coils only, AXON capacitors except woofer section and resistors MEXICO and DALE.
Thank you all.
There are a number of close model numbers. No, the sibilance is often by design! 🙂
The DA25BG is from Madisound. It is an extended frequency range Aluminum dome variant (dual magnets) so goes deeper. I'm not sure how many of these are still around, it could be discontinued.
You could also come over to the soft dome and try the DX25TG59
The DX25 has about the same sensitivity.
The DA25BG is from Madisound. It is an extended frequency range Aluminum dome variant (dual magnets) so goes deeper. I'm not sure how many of these are still around, it could be discontinued.
You could also come over to the soft dome and try the DX25TG59
The DX25 has about the same sensitivity.
Thank you for the answer.
I would like to avoid import from US cause the import charges.
Are those models you mentioned better replacement then those I found?
If sybilance is design problem, what can I do to reduce it?
I did read plenty of reviews about these speakers, seems no one who uses them complain about this.
But some people can hear harshness developed after damage on aluminium dome.
I would like to avoid buying mutiple tweeters to find the same result if it is true, but is it true?
If I could find the drop in replacement tweeter which will solve it, that would be great.
Maybe tweeter with less sensitivity, higher resistance, maybe even better one as an upgrade. Or some easy change in crossover to dampen it, or change its roll off characteristics.
I am inexperienced with modifying, but can do essential soldering.
Cheers
Odoslané z A0001 pomocou Tapatalku
I would like to avoid import from US cause the import charges.
Are those models you mentioned better replacement then those I found?
If sybilance is design problem, what can I do to reduce it?
I did read plenty of reviews about these speakers, seems no one who uses them complain about this.
But some people can hear harshness developed after damage on aluminium dome.
I would like to avoid buying mutiple tweeters to find the same result if it is true, but is it true?
If I could find the drop in replacement tweeter which will solve it, that would be great.
Maybe tweeter with less sensitivity, higher resistance, maybe even better one as an upgrade. Or some easy change in crossover to dampen it, or change its roll off characteristics.
I am inexperienced with modifying, but can do essential soldering.
Cheers
Odoslané z A0001 pomocou Tapatalku
I had a look at the stereophile review of your speaker. 10" and 4" bass and mid, and the venerable old vifa metal dome.
I don't like the 4 ohm impedance much, and it has a nasty narrow impedance peak at about 2.5 kHz that might be the source of the sibilance. If I were you, I'd dissasemble those tweeters with the three screws and fix the dents. Ferrofluid may need cleaning out with a blotter and replacing. I know you can buy it in Holland. These are standard sort of 90dB 4.6R tweeters, on 104mm plates, so replacement is easy too.
It is easy enough to adjust tweeter level with the resistors in the tweter circuit.
You'd need to decipher the crossover circuit to fix the impedance, but a 7.5R 7W resistor in series with a 0.68uF cap across the tweeter itself can tame top end brightness. Naim amps are sensitive to top end impedance, AFAIK, so this is worth trying. Hope that helps.
I don't like the 4 ohm impedance much, and it has a nasty narrow impedance peak at about 2.5 kHz that might be the source of the sibilance. If I were you, I'd dissasemble those tweeters with the three screws and fix the dents. Ferrofluid may need cleaning out with a blotter and replacing. I know you can buy it in Holland. These are standard sort of 90dB 4.6R tweeters, on 104mm plates, so replacement is easy too.
It is easy enough to adjust tweeter level with the resistors in the tweter circuit.
You'd need to decipher the crossover circuit to fix the impedance, but a 7.5R 7W resistor in series with a 0.68uF cap across the tweeter itself can tame top end brightness. Naim amps are sensitive to top end impedance, AFAIK, so this is worth trying. Hope that helps.
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I dented one of mine, I took it apart and used something soft and rounded to carefully massage the dents out from behind the dome. It then measured virtually the same as the undented one.
If you want to replace, you could try one of the SEAS tweeters.
If you want to replace, you could try one of the SEAS tweeters.
Hi guys,
thanks much for the answers!
I dismantled both tweeters today, the dents are shallow now, but I really don't like the pierced one, they need to be replaced. As I know already how the diaphragm looks like it should be easier to find just great condition dome from similar series D25 tweeters and swap them.
I soldered 5.6 Ohm/10W resistor on + tweeter contact along with about 1uF russian PETP capacitor between both tweeter contacts and result was different speakers response then before, much more bass, tamed trebles. Well, too big sound, thus I removed the capacitors.
They sound much better now, but I am still not in final stage.
Next steps will be the new diaphraghms, rca attenuators on preamp output (as it might be overloaded) and lower resistor values to play with to get the right balance.
Also I can try to refill the ferrofluid later, could I get contact where can I buy it from Holland Steve?
I'll keep it like that for some time, but I still suspect that alluminium dome is not what Naim likes, just a guess.
These speakers are old, but I believe they will sing from what I can hear now, they are lovely 🙂
Thanks again!
thanks much for the answers!
I dismantled both tweeters today, the dents are shallow now, but I really don't like the pierced one, they need to be replaced. As I know already how the diaphragm looks like it should be easier to find just great condition dome from similar series D25 tweeters and swap them.
I soldered 5.6 Ohm/10W resistor on + tweeter contact along with about 1uF russian PETP capacitor between both tweeter contacts and result was different speakers response then before, much more bass, tamed trebles. Well, too big sound, thus I removed the capacitors.
They sound much better now, but I am still not in final stage.
Next steps will be the new diaphraghms, rca attenuators on preamp output (as it might be overloaded) and lower resistor values to play with to get the right balance.
Also I can try to refill the ferrofluid later, could I get contact where can I buy it from Holland Steve?
I'll keep it like that for some time, but I still suspect that alluminium dome is not what Naim likes, just a guess.
These speakers are old, but I believe they will sing from what I can hear now, they are lovely 🙂
Thanks again!
https://www.madisoundspeakerstore.c...eak-voice-coil-600058-for-d27tg35-or-d27tg45/
Pretty sure that silk dome voicecoil replacement fits yours.
Pretty sure that silk dome voicecoil replacement fits yours.
I have the Vifa catalogue in front of me, and unfortunately the 27 series have a 26mm voicecoil, whereas the 25 series has 25mm.
The ferrofluid supplier is also a supplier of new surrounds, IIRC, but you must google them. FWIW, impedance correction can also be applied across the cabinet terminals. It iincreases the stability margin in the amp with a zobel type.
The ferrofluid supplier is also a supplier of new surrounds, IIRC, but you must google them. FWIW, impedance correction can also be applied across the cabinet terminals. It iincreases the stability margin in the amp with a zobel type.
from the link:
"If you have one of the metal domes, like the D25AG05-06 or the D25AG35-06, you could use this dome but the diffuser on your tweeter will roll off the highs. Consider clipping the diffusor off. If you prefer a metal dome, the Seas 27TBFC/G is an excellent replacement and considered an upgrade."
Very useful link to Madison I overlooked that one, thanks 🙂
According to Tymphany D27TG35-06 Spec Sheet it has 25mm voice coil.
And Seas possible replacement tweeters 26mm voice coil.
I am wiser now with 4 options for direct drop in replacements:
1 - SH aluminium diaphragms to replace damaged original ones
2 - new ScanSpeak Voice Coil (600058) for D27TG35 (soft dome)
3 - new SEAS Prestige 27TBFC/G (H1212) Aluminum/Magnesium Dome Tweeter
4 - new SEAS Prestige 27TDFC (H1189) Textile Dome Tweeter (or 27TFFC)
Still, in first two cases one question remaining is how ferrofluid insufficiency influences a tweeter performance? Does it sound brighter, harsher, duller?
And last thing is that Seas tweeters would be new, reasonably priced, considered as an upgrade, and could have better behaviour touching top end impedance. At least what my unexperienced I can see from the graphs. Do I need more to know? 🙂 It might solve the sibilance problem, without touching anything in crossover, and that is the aim.
Thank you all.
According to Tymphany D27TG35-06 Spec Sheet it has 25mm voice coil.
And Seas possible replacement tweeters 26mm voice coil.
I am wiser now with 4 options for direct drop in replacements:
1 - SH aluminium diaphragms to replace damaged original ones
2 - new ScanSpeak Voice Coil (600058) for D27TG35 (soft dome)
3 - new SEAS Prestige 27TBFC/G (H1212) Aluminum/Magnesium Dome Tweeter
4 - new SEAS Prestige 27TDFC (H1189) Textile Dome Tweeter (or 27TFFC)
Still, in first two cases one question remaining is how ferrofluid insufficiency influences a tweeter performance? Does it sound brighter, harsher, duller?
And last thing is that Seas tweeters would be new, reasonably priced, considered as an upgrade, and could have better behaviour touching top end impedance. At least what my unexperienced I can see from the graphs. Do I need more to know? 🙂 It might solve the sibilance problem, without touching anything in crossover, and that is the aim.
Thank you all.
I have also straightened out dented domes, and they ended up sounding fine (as long as you don't look too close!). So you should consider leaving them alone, pinhole and all, except to replenish the ferro fluid.
I agree with what previous people have said about the battered metal domes. I think they ought to work well enough. A pinhole is usually best filled with some glue to prevent further fractures. I'd think epoxy resin on a matchstick would be a plan. In fact scanspeak think a cone sliced and filled with glue is a good idea. 😱
IMO, metal domes sound like metal domes. A zobel only takes the top end down above 5kHz. Ferrofluid is not a huge factor in sound unless it solidifies. You should have seen some brownish oil in the gap when you took the tweeters apart.
The SEAS looks a good replacement. But level might need a dB reduction. You really need to dissect the crossover. Then you know how to adjust it. Look at Troels Gravesen's SEAS 3 way classic to know what to expect.
I suspect the sibilance is a crossover problem allied to a Naim amp that is on the verge of instability.
IMO, metal domes sound like metal domes. A zobel only takes the top end down above 5kHz. Ferrofluid is not a huge factor in sound unless it solidifies. You should have seen some brownish oil in the gap when you took the tweeters apart.
The SEAS looks a good replacement. But level might need a dB reduction. You really need to dissect the crossover. Then you know how to adjust it. Look at Troels Gravesen's SEAS 3 way classic to know what to expect.
I suspect the sibilance is a crossover problem allied to a Naim amp that is on the verge of instability.
This is a golden opportunity to try a multivariable experiment on the cheap: for only the cost of some ferrofluid and a pair of silk voicecoils, you get to try metal dome and silk dome with and without ferrofluid, all in the same motor and cabinet. That will suck you in!
Peerless by Tymphany D27TG35-06 1" Silk Dome Tweeter
For the price of the diaphragm, a whole tweeter 😉
For the price of the diaphragm, a whole tweeter 😉
Sure, if you just wanted to plop in a nice tweeter and play tunes.
But how can you have any pudding when you haven't eaten your meal?
But how can you have any pudding when you haven't eaten your meal?
Just won a pair of new new pair of Seas 27TDFC tweeters for half price of new 🙂
They should arrive at the end of this week.
Looks the Seas specs are pretty close to original Vifa including sensitivity.
If the sibilance is caused by incompatibility problem between Hales and Naim it should show.
I hope it is not, then can continue with other experiments with domes and ferrofluid for original Vifa.
Aluminium domes will stay as they are, with a little repair of the pin hole.
Let's see how Hales with Seas will sound 🙂
They should arrive at the end of this week.
Looks the Seas specs are pretty close to original Vifa including sensitivity.
If the sibilance is caused by incompatibility problem between Hales and Naim it should show.
I hope it is not, then can continue with other experiments with domes and ferrofluid for original Vifa.
Aluminium domes will stay as they are, with a little repair of the pin hole.
Let's see how Hales with Seas will sound 🙂
Thank you, I had a look at it. The same 27TFFC tweeter I used once for Tony Gee's Tempo clone. I liked those speakers, sweet midrange and clean trebles. My friend still uses them in his living room. Thus I have an idea about the new 27TDFC, should be fine 🙂
Hi guys,
so this is my finding after some time of trials. I am sorry to tell, but Naim NAP 250 olive is not able to drive the Hales speakers. The speakers load creates havoc in high frequencies response of NAP, it comes into some kind of oscillation or what, that was what I experienced in sound I strongly believe.
The Seas tweeter itself s fine as replacement, at least I can not hear a difference between original Vifa and Seas.
As power amp I used Parasound New classic series 275v2. Not much info about it. I set up its load for 2-3 Ohm speakers as Hales drops to 3 Ohm. Also I applied 40 Hz filter to make it work not so hard, even though 20 Hz filter should be okay too.
I tried the Parasound with Naim NAC 82, preamp output of Yamaha CA 800 and preamp output of Parasound R/HD300II and the results are positive touching sibilance issue. Seems no problem with Hales crossover. Sometimes music can sound a little electronic in treble response, which might mean that still no great match achieved for whatever reason.
The Parasound 275v2 has just 2x90W power as it is smallest amp in its range. However it can control the speakers much better up to average listening levels.
During those trials I found that the NAP 250 might not be able to drive my Dynaudio too, in sense of proper drivers control. It sounds great at first impression, however lower midrange/ bass has boomy character more then desireable. Upper midrange and trebles are very clear though. Parasound / NAC82 with Dynaudio clearly does not sound so refined in upper midrange/ trebles region, but the drivers control is obvious and sound more neutral. Midrange comes in full, not only part of it and bass is tighter, not overblown. The biggest surprise was 30W Parasound R/HD-300, again in terms of drivers control for Dynaudio. It struggled with Hales, but what I could hear from Dynaudio was another learning experience. Not perfect sound of course, but a lot of improvement. It has something to do with its high current discrete design. Except the extremes, like too much very low frequencies coming into speakers and harsh trebles, it was able to wake up the speakers the way I did not expect!
Mainly how it influenced the clarity of whole music presentation and revealing of plenty of details blurred before.
The R/HD-300II is on the way to technician, who will try to sort out its output characteristics for my liking.
So everything started with Vifa tweeter replacement, and ended with unexpected results.
Hope someone will find it useful.
Cheers guys!
Odoslané z A0001 pomocou Tapatalku
so this is my finding after some time of trials. I am sorry to tell, but Naim NAP 250 olive is not able to drive the Hales speakers. The speakers load creates havoc in high frequencies response of NAP, it comes into some kind of oscillation or what, that was what I experienced in sound I strongly believe.
The Seas tweeter itself s fine as replacement, at least I can not hear a difference between original Vifa and Seas.
As power amp I used Parasound New classic series 275v2. Not much info about it. I set up its load for 2-3 Ohm speakers as Hales drops to 3 Ohm. Also I applied 40 Hz filter to make it work not so hard, even though 20 Hz filter should be okay too.
I tried the Parasound with Naim NAC 82, preamp output of Yamaha CA 800 and preamp output of Parasound R/HD300II and the results are positive touching sibilance issue. Seems no problem with Hales crossover. Sometimes music can sound a little electronic in treble response, which might mean that still no great match achieved for whatever reason.
The Parasound 275v2 has just 2x90W power as it is smallest amp in its range. However it can control the speakers much better up to average listening levels.
During those trials I found that the NAP 250 might not be able to drive my Dynaudio too, in sense of proper drivers control. It sounds great at first impression, however lower midrange/ bass has boomy character more then desireable. Upper midrange and trebles are very clear though. Parasound / NAC82 with Dynaudio clearly does not sound so refined in upper midrange/ trebles region, but the drivers control is obvious and sound more neutral. Midrange comes in full, not only part of it and bass is tighter, not overblown. The biggest surprise was 30W Parasound R/HD-300, again in terms of drivers control for Dynaudio. It struggled with Hales, but what I could hear from Dynaudio was another learning experience. Not perfect sound of course, but a lot of improvement. It has something to do with its high current discrete design. Except the extremes, like too much very low frequencies coming into speakers and harsh trebles, it was able to wake up the speakers the way I did not expect!
Mainly how it influenced the clarity of whole music presentation and revealing of plenty of details blurred before.
The R/HD-300II is on the way to technician, who will try to sort out its output characteristics for my liking.
So everything started with Vifa tweeter replacement, and ended with unexpected results.
Hope someone will find it useful.
Cheers guys!
Odoslané z A0001 pomocou Tapatalku
I think you get about 1 mark out of 10 there, my friend! Sorry. You tried the Zobel with 5.6R and 1uF, which was excessive IMO, but it certainly didn't increase the bass, because it only affects the top end above 5kHz.
This was the right advice:
It assumes a certain willingness to roll your sleeves up. Once you have a rough schematic of the crossover, glaring errors can be spotted and fixed. Otherwise you are a blind man poking about without a stick. And there obviously are some errors. A properly designed 3 way looks like this:
SEAS-3-Way-Classic
Compare your impedance with the one Troels designs for, below. Much easier load, hence no problems with ANY amp! 😎
All this talk of various brands doesn't illuminate the problem at all. It's down to crossover and driver choice by Hales.
This was the right advice:
It assumes a certain willingness to roll your sleeves up. Once you have a rough schematic of the crossover, glaring errors can be spotted and fixed. Otherwise you are a blind man poking about without a stick. And there obviously are some errors. A properly designed 3 way looks like this:
SEAS-3-Way-Classic
Compare your impedance with the one Troels designs for, below. Much easier load, hence no problems with ANY amp! 😎
All this talk of various brands doesn't illuminate the problem at all. It's down to crossover and driver choice by Hales.
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