I'm searching for the most efficient (voltage sensitive) 19mm dome tweeter on the market. It has to be in the low 90s dB/2.83v range and easily reach past 15k off axis to qualify. Its needed for a small nearfield monitor with a very hot midbass.
My initial choice was the beloved Seas 22TAF, but its technically a larger driver with average off axis performance. The 22 TFF is similar and not quite as sensitive. SB makes some smaller units, but they're also not quite as loud.
If anyone has an idea, please let me know.
My initial choice was the beloved Seas 22TAF, but its technically a larger driver with average off axis performance. The 22 TFF is similar and not quite as sensitive. SB makes some smaller units, but they're also not quite as loud.
If anyone has an idea, please let me know.
What is the impedance of that tweeter and what is the midbass in the game?
If the average 19mm dome unit with impedance of 8 ohm is about 87-89dB at 2.83V RMS, then the same one only with impedance of 4 ohm is more efficient by 3dB at 2.83V because it gets twice the power (2W).
You also have relatively efficient ribbon tweeters with a narrow ribbon. They have excellent horizontal dispersion and poor vertical dispersion. Fountek NEO CD3.0 or simmilar. It is a horn tweeter.
If the average 19mm dome unit with impedance of 8 ohm is about 87-89dB at 2.83V RMS, then the same one only with impedance of 4 ohm is more efficient by 3dB at 2.83V because it gets twice the power (2W).
You also have relatively efficient ribbon tweeters with a narrow ribbon. They have excellent horizontal dispersion and poor vertical dispersion. Fountek NEO CD3.0 or simmilar. It is a horn tweeter.
Found some unusual ones on THLP (where you can search by SPL and possibly more parameters if logged in):
Sica LP90 (90mm diameter faceplace) 94db
Monacor DT-19SU (91db)
SB 21SDC-C000-4 (91db)
Off-axis measurements look quite good on dibirama
https://www.dibirama.altervista.org...p90-28-n92-tw-tweeter-1-1-8-ohm-120-wmax.html
Sica LP90 (90mm diameter faceplace) 94db
Monacor DT-19SU (91db)
SB 21SDC-C000-4 (91db)
Off-axis measurements look quite good on dibirama
https://www.dibirama.altervista.org...p90-28-n92-tw-tweeter-1-1-8-ohm-120-wmax.html
92dB & 2,83V = 89dB 1W 1m (the driver is 4ohm). We don't yet have any information about the impedance and which mid bass it is combined with. I doubt any small mid bass has such a high sensitivity.
Sensitivity is voltage related, Efficiency is watt related. Driver with higher sensitivity will create higher SPL, right? I think that is the point of Sensitivity concept. It does not matter if it is 4ohm or 8ohm and that 4ohm draws more current from the amp.
Efficiency, per watt, is quite uselless number for loudspeaker design. Sensitivity, on the other hand, matters a lot.
Efficiency, per watt, is quite uselless number for loudspeaker design. Sensitivity, on the other hand, matters a lot.
Due to the variable impedance of the driver, the measurement at 2.83VRMS makes more sense, and is also easy to perform. The sound pressure data at 1W&1m is calculated based on measurements at 2.83VRMS, I assume.
Thanks to all for some great suggestions. The SS 7120 looks very nice but likely very expensive.
The smaller Wavecors are a good option too.
As said before, it needs to be low 90s DB / 2.83V, regardless of impedance. It can be a 4 ohm tweeter, so both 4 and 8 ohms will work fine. Just need to optimize the xover. Its 2.4k 3rd order crossed to a custom SS 7" I've never seen. Looks alot like the older driver found in the PMC 100, close to the SS 18W8542. It measures over 91dB @ 6ohms nominal. The tweeter was an older SS 19mm dome, so no surprise it didn't hold up.
There's alot of room to enlarge the tweeter, so no issues with a larger faceplate.
The smaller Wavecors are a good option too.
As said before, it needs to be low 90s DB / 2.83V, regardless of impedance. It can be a 4 ohm tweeter, so both 4 and 8 ohms will work fine. Just need to optimize the xover. Its 2.4k 3rd order crossed to a custom SS 7" I've never seen. Looks alot like the older driver found in the PMC 100, close to the SS 18W8542. It measures over 91dB @ 6ohms nominal. The tweeter was an older SS 19mm dome, so no surprise it didn't hold up.
There's alot of room to enlarge the tweeter, so no issues with a larger faceplate.
@raymondj I considered that tweeter but it won't go low enough and stay clean. The top end is also not that extended. Good for the price though.
The cost isn't really a problem within reason. $100 per tweeter is an acceptable cost. Its for a friends home studio. Hes picky about the top end extension.
The cost isn't really a problem within reason. $100 per tweeter is an acceptable cost. Its for a friends home studio. Hes picky about the top end extension.
With a 6.5" midbass I would go for a 1" dome tweeter and there is a very large choice on the market. 3/4" dome is not the optimal choice for my opinion. Those smaller tweeters are somehow more for pairing with 4-5" midbass.
I can sell one for $150. Only use was to design waveguides for it. Never used in a speaker.
@augerpro I appreciate the offer. The closer I looked at it, I realized it isn't as suitable as some other models, especially considering the cost. Were you able to see any benefit from a WG on that tweeter (assuming you had the tweeter for WG design purposes)?
The Seas 22TAF still looks attractive, but the huge surround causes some concern with off axis behavior, being it acts more like extra emissive surface area. I like the fact its a metal dome, which is more accurate up top compared to a soft dome.
The Seas 22TAF still looks attractive, but the huge surround causes some concern with off axis behavior, being it acts more like extra emissive surface area. I like the fact its a metal dome, which is more accurate up top compared to a soft dome.
I tend to agree. Looking at some smaller bodied 25mm domes, the SB26STCN looks good off axis and still has the benefit of being a larger dome. The problem with that one however is the higher than average HD crossed lower. I've tried that tweeter crossed around 2.5k 2nd order and didn't like it. Around 3k its great and has plenty reserves.
And what model tweeters are on the speakers now? SS D2008 or D2010? First one has diameter of 92mm, second one 98mm.
With those dimensions of the front panel it is difficult to find a 25mm tweeter, they are usually 104mm or more. A picture of those speakers would help.
With those dimensions of the front panel it is difficult to find a 25mm tweeter, they are usually 104mm or more. A picture of those speakers would help.
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I think the results are pretty decent: https://www.somasonus.net/scanspeak-revelator-d2104-7120
I'd like to try my newer hybrid contour, but haven't had time.
@NIXIE62 I don't have the monitors here as they're still in use at owner's studio. The existing tweeters are about 100mm diameter, just shy of a typical smaller Audax unit. The exact model number is unknown, being tweeters don't have the SS markings. I just know they use SS VCs, the exact ones not being available anymore. This is why he wants to replace them. Some surgery will be needed to fit another tweeter model. There's plenty of room to enlarge the tweeter opening and install a larger unit.
