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I am told my amps wont sound their best on these 98db speakers because they are 250wpc

ABall

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So I am looking at a change of speakers and I emailed the designer with my room size and amplification but he has recommended a cheaper smaller model, it appears his decision is based somewhat on the grounds that super sensitive speakers work best with low wattage valve amps not hi power amps. I did call the designer of my amps and he was a bit perplexed but said he could understand the thought process but did not elaborate. So what is the science behind this? The other thing I dont understand is he says the smaller one will produce more bass in a smaller room, but its the same design all be it with a 10" instead of 12" driver. Dont get me wrong this guy has earned his stars so i dont want to brush this off, I just want to understand. Here is the explanation on the bass section of the speakers Im looking at. I am particularly intrigued by the claim that this design can have the best bass in a big room and because a small room has less floor space it will not produce so much bass and therefore still produce "strong" articulate bass. They sound like my dream speakers.....


Bass Horns


The Bastanis line of passive powered speakers uses backloaded floor- firing bass-horn cabinets. This sounds complicated but there is an easy explanation which shows the big advantages of backloaded bass-horns for passive powered speakers.



  • The horn transforms the air- movement from the drivers cones to a much bigger surface at the horn-mouth. This increases the possible max. dynamics enormously because for the same spl as without the horn there is a small percentage of cone- movement only.
  • This also means that the amount of physical damping of the drivers resonance by the load of air is much bigger and so the required electrical damping is extremely low which is very good for the soundquality of tubed amps.
  • The increased physical resistance of the basses coming from bass-horn cabinets is the only way to give high efficient passive powered speakers strong bass- response with the same efficiency as the midrange, any conventional sealed or bass-reflex cabinets could offer the basses with much lower efficiency only.
  • The floor firing bass-horns are a big step up from the usual giant bass-horns because they work as well offering efficient, fundamental and dynamic basses from cabinets with common dimensions.
  • The floor firing bass-horns react self- adjusting to the room and the placement, big rooms mean big floor- space, big virtual opening of the horn-mouth and so maximum contribution of the basses. Smaller room- spaces and close to wall- placement means smaller floor- space, smaller virtual horn-mouth and less contribution of the basses, so the bass- response stays strong and clean.


The Bastanis floor- firing bass-horn speakers are the most excellent way to get the unlimited basses you always were looking for combined with high efficiency, compact sized cabinets and self- adjusting characteristics.
 

solderdude

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#2
Question:

Have you auditioned the speakers in your home on your current system ?
The Bastanis series is 400W and 600W rated yet 250W with 100dB/W/m would be too powerful ?
 
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rdenney

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Amps usually have a noise floor, and the higher that is, the easier it will be to hear. The more sensitive the speakers, the louder that background noise will be. If a speaker produces 100 dB SPL at one watt, one meter, then 250 watts will add a 24 dB increase in power, or 124 dB SPL, assuming it doesn't run out of steam. That's at one meter. At 12 feet (a long distance in most houses), distance losses will be compensated by room gain, and it might knock off a dozen dB to 112 dB--and that's in a pretty dry room. Add three dB for two channels. So, maybe 130 dB SPL at a one-meter sweet spot.

I just listened to speakers at 110 dB SPL peaks, and it was deafening in my living room. I was closer, but my speakers aren't as sensitive and my amps not as powerful.

But if that's what the amps produce at peak, and if they have a -100 dB noise floor, the noise will be 30 dB at that one-meter sweet spot. That's pretty quiet, though you'll hear the hiss if you are right next to your speaker. But if the noise floor of the amps is -70 dB (not that uncommon in the old days, at least), the hiss will be at 60 dB, which will be annoyingly loud anywhere in the room.

So it depends on how quiet the amp is. Modern amps are pretty quiet.

I would think that if these speakers (at least the Wildhorn model) are rated for 400 watts of amplifier power, they are good for largish PA systems or movie theaters. I can't imagine humans being able to tolerate their sensitivity at their rated power in any normal home, even a big one.

As for the 250-watt amp, I think you'll never get above 8 O'Clock on the volume control. That's probably what your store guy is saying.

But it's not just about tubes--there are plenty of very clean somewhat lower-powered solid-state amps, too. A single Benchmark seems like it could really have fun with these, even in a very large space.

Rick "wondering if these horns are really that sensitive" Denney
 
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ABall

ABall

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Thread Starter #4
Questions:

Do you want different speakers ?
Are you troubled by audible/distracting noise coming from the speakers ?
Is the current system not loud enough ?
I didnt want to bog down the post with all the background so I was just looking for a scientific reason for his response, but since you asked...

Do I want different speakers? I still havent found what im looking for so probably.
Am I troubled by audible/distracting noise coming from the speakers ? No Its not noise that distracts me.
Is the current system not loud enough ? Volume is not an issue, I am looking at these speakers not because they are high spl but because they promise everything Ive been looking for in the 15 years at my current address.
Basically I desire a very particular sound that makes me smile and want to listen to my music, I have used open baffle, ported, transmission line and sealed and I have also made some frankenstein monsters that came very close. For transparency I have not heard better than my linear array of Jorden 's that were designed to run with no crossover, I even removed the crossover from a pair of Glastonbury speakers, bolted my array on the sides and lived happy for a while but obviously I had created a monster. This did pave the way for my next venture which was open baffle Hawthorn Audio Silver Iris Duets, these were 15" full range custom eminence drivers with a compression tweeter screwed in the centre and a 15" eminence bass augmented driver that were actively powered by 2 XTZ sub amps, I have hung onto the bass drivers and amps because they have brought the most joy in my room. However I hated the tweeters, I even upgraded to a model which was recommended by the designer that I could not afford at original order but I just couldnt live with with the top end after living with the JX53s which I also still have but my room just isnt long enough for big OB's to work properly. Now I have come to the conclusion I aint no speaker designer, as others have said its part science and part witchcraft...... I know my room has restrictions but I dont want to treat it, its my lounge and its shared with my wife who has been bloody amazing given the monsters ive had in it! Imaging wise the best ive heard is the full range linear array and my Tannoy Xt6f's down to the concentric design but they are ported so are doing rear HT duties. I am probably asking too much but Club-27 audio are offering what look like dream speakers at an affordable price with the claim they out perform speakers many many times more. To be honest my current front speakers are the best Ive had here, IPL S2TLK CD3 Ribbon , they do make me smile a lot, they have the ability to hit 26hz in the right room though so when its loud and the bass gets really deep and fast they remind me its not perfect.
 
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ABall

ABall

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Amps usually have a noise floor, and the higher that is, the easier it will be to hear. The more sensitive the speakers, the louder that background noise will be. If a speaker produces 100 dB SPL at one watt, one meter, then 250 watts will add a 24 dB increase in power, or 124 dB SPL, assuming it doesn't run out of steam. That's at one meter. At 12 feet (a long distance in most houses), distance losses will be compensated by room gain, and it might knock off a dozen dB to 112 dB--and that's in a pretty dry room. Add three dB for two channels. So, maybe 130 dB SPL at a one-meter sweet spot.

I just listened to speakers at 110 dB SPL peaks, and it was deafening in my living room. I was closer, but my speakers aren't as sensitive and my amps not as powerful.

But if that's what the amps produce at peak, and if they have a -100 dB noise floor, the noise will be 30 dB at that one-meter sweet spot. That's pretty quiet, though you'll hear the hiss if you are right next to your speaker. But if the noise floor of the amps is -70 dB (not that uncommon in the old days, at least), the hiss will be at 60 dB, which will be annoyingly loud anywhere in the room.

So it depends on how quiet the amp is. Modern amps are pretty quiet.

I would think that if these speakers (at least the Wildhorn model) are rated for 400 watts of amplifier power, they are good for largish PA systems or movie theaters. I can't imagine humans being able to tolerate their sensitivity at their rated power in any normal home, even a big one.

As for the 250-watt amp, I think you'll never get above 8 O'Clock on the volume control. That's probably what your store guy is saying.

But it's not just about tubes--there are plenty of very clean somewhat lower-powered solid-state amps, too. A single Benchmark seems like it could really have fun with these, even in a very large space.

Rick "wondering if these horns are really that sensitive" Denney
LOl, they say these "Real" 98db speakers are more sensitive than other speakers that claim to be 100, I do believe them, Robert Bastani seems like a good guy, hes not saying they are 100 hes saying others are making false claims. Its not about listening to music at high spls, its about my amps only using very little of there potential power and them not working at there best at that range. Here is part of his replay and the bit I would like to understand the science on.

"The higher efficiency of the Amy speakers is a challenge for any higher wattage amp and only very few of them behave well at extremely low wattage. The Kurt also are high efficient but not this special in the requirements regarding the amplification".
 

AnalogSteph

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#6
Sounds like you have plenty of experience with the "throw shit at the wall and see what sticks" approach to speaker selection. I don't see any kind of methodical approach whatsoever though. You seem to have little if any understanding of why things do or don't work in your room. That's clearly a problem. A clever salesman could sell you most anything.

A few questions:

How big is your room, how lively are the acoustics, what is listening distance like? (The odd picture may be able to stand in for a novel if need be.)

You seem to have tried lots of exotica, but have you ever had what conventional wisdom would suggest to be a good speaker? Flat on-axis and nice even dispersion h/v?

I am not entirely surprised that you had good results with a line array of widebanders... it should give you moderately wide horizontal and fairly tight vertical dispersion in the highs, eliminating a good bit of diffuse sound up there in less than stellar acoustics. Some others mentioned I can't make as much sense of, like your current fronts. 26 Hz... the specs don't say how many dB down, I'd guess at least 10. You can tune a TML to below fs (which is 56 Hz for this driver), but I have no idea how well that works.

You have never looked into measurements and room EQ, have you? Also, are you aware that not all acoustic elements are an eyesore and some are actually made to be quite decorative?

A large-baffle speaker might well be the right thing for you... but if so, perhaps one from a company that doesn't use dubious techniques like minimalist crossovers and can back up its claims with some measurements at least. The bigger the R&D department the better. (One man shows can be good if run by industry experts, otherwise I'd remain skeptical.) There is even the odd PA speaker that performs well by modern standards.
 

Helicopter

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Those Bastanis look cool. Your 250w amp, if quiet, should be fine.

I think the speakers are likely designed to allow tube amps to perform their best, and many speakers do not work well with some tube amps, in my experience. The reverse is not so true however. Speakers that are amp friendly are just more flexible... they should work fine with solid state.

I pretty much just have horn speakers so I can play around with different stuff, like tubes or early consumer grade solid state radios, and so on.
 
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most ASR reviews I've seen show that distortion measurements improve as output increases, up until the amp begins to clip.. unless I've misunderstood all those graphs?

An amp with 250w on super sensitive speakers won't need to output much to be super loud, in which case there will be more distortion, assuming my sentence above is true.
 

SIY

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most ASR reviews I've seen show that distortion measurements improve as output increases, up until the amp begins to clip.. unless I've misunderstood all those graphs?
Because that graph is THD + N, at lower powers, the N dominates. That's why you see the downward slope until much higher power.
 

Helicopter

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Relatively low absolute noise from your amp is the name of the game with 100dB+ speakers. That is easier to pull off with less output, but there are still quiet powerful amps.
 
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rdenney

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It’s the ratio that’s confusing you. Base noise may remain about the same the same, but as the power you use goes up, the ratio of that increasing signal to that more constant base noise goes down, so you have better looking numbers. Noise and distortion are nearly always represented as ratios.

But if the base noise is low enough, the sound will be just as good.

If the base noise is loud enough to be objectionable, though, a smaller amp with the same noise ratio will be quieter.

It’s best to size an amp so that the peak clean power corresponds yo the loudest sounds you want to make, plus a little headroom. But that doesn’t mean it’s bad to have a bigger amp, if it’s quiet.

Rick “wondering what a couple of good subs added to the line array speakers might do” Denney
 

SIY

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Relatively low absolute noise from your amp is the name of the game with 100dB+ apeakers. That is easier to pull off with less output, but there are still quiet powerful amps.
^This. As an example, here's a 1W spectrum of the Orchard amp, with 0dB = 2.83V. Even with really efficient horns, you're unlikely to be able to hear any noise.

Figure 6.PNG
 

boXem | audio

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^This. As an example, here's a 1W spectrum of the Orchard amp, with 0dB = 2.83V. Even with really efficient horns, you're unlikely to be able to hear any noise.

View attachment 117762
Without fft size, this graph doesn't show anything about the noise :)
 

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LOl, they say these "Real" 98db speakers are more sensitive than other speakers that claim to be 100, I do believe them, Robert Bastani seems like a good guy, hes not saying they are 100 hes saying others are making false claims. Its not about listening to music at high spls, its about my amps only using very little of there potential power and them not working at there best at that range. Here is part of his replay and the bit I would like to understand the science on.

"The higher efficiency of the Amy speakers is a challenge for any higher wattage amp and only very few of them behave well at extremely low wattage. The Kurt also are high efficient but not this special in the requirements regarding the amplification".
Sounds like a 'first watt' proponent, i.e. "most SS amps don't cut-it".
 

solderdude

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I didnt want to bog down the post with all the background so I was just looking for a scientific reason for his response, but since you asked...

Do I want different speakers? I still havent found what im looking for so probably.
.....
Another Question:

Have you auditioned these speakers in your home on your current system ?
I mean there could be 100's of testimonials but these aren't in your living room.

The Bastanis series is 400W and 600W rated yet 250W with 100dB/W/m would be too powerful ?

Consider many tube amps have higher output resistance than usual which might 'work well' with these speakers.
You can always simulate this by adding a small resistance in series with the cable to see if that improves it.

In any case... one should always audition speakers in their home for at least a week.
Given your response this seems to be the best advise for you.
 
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ABall

ABall

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Thanks for the reply Analog, even though its not actually answering the question I asked but thankfully others have and Im very grateful for all the input, its what makes this forum great. I would like to address a few of your criticisms, ive never purchased anything from a clever salesman but your right my choices didnt involve me methodically posting on forums, measuring my room and auditioning speakers. I have purchased 2 pairs of speakers from a shop in my life, some sony APM's in the 80's and a pair of celestion 7000's in the 90's, I gave the 7000's to my nephew a couple of years ago because they were wasted doing rear duties on my HT. I purchased the Townsend Glastonbury speakers from Tom Evans in the 90's, a dear friend and I used to visit a few up and coming manufacturers at there homes, Tom didnt want to sell them for a long time but then he designed the FR1 so was forced to if he wanted to pursued the public he was invested in them. I had these for almost 20 years so not fleeting purchases. The reason I tried the OB is because my close friend recommended them to me, he had purchased a set and had the same size room. These were a DIY speaker and the drivers were imported from america so not really a try for a week thing. The Tannoys I purchased from my friend because he needed the money, I did offer the money but he had made his mind up and had them on ebay, these replaced my 7000's as rears. I already had the IPL's from ebay so again not a trial type purchase and for the most part I am happy with them.

Day job calling now so back later to read the other helpful replies and comment....
 
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ABall

ABall

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Rick “wondering what a couple of good subs added to the line array speakers might do” Denney
:D My thoughts exactly when I was experimenting with all these designs, the problem with the JX53's, (sorry I said 92s, they were the mids) is they are tweeters not full range, they didnt use a crossover but the range was built into the enclosure design so they didnt go low enough for my OB bass drivers, certainly not low enough to reach the crossover built into the plate amps, I think its 250hz and the enclosure restricted the array to 120hz. They were a match for the JX125's from memory which were used in the Glastonbury's but I never got round to building a crossover for the speaker I created bolting the array on the side of them. I did have a lot of fun....

most ASR reviews I've seen show that distortion measurements improve as output increases, up until the amp begins to clip.. unless I've misunderstood all those graphs?
An amp with 250w on super sensitive speakers won't need to output much to be super loud, in which case there will be more distortion, assuming my sentence above is true.
I guess, but only guess this is what he is alluding too.

Relatively low absolute noise from your amp is the name of the game with 100dB+ apeakers. That is easier to pull off with less output, but there are still quiet powerful amps.
I think I am going to find out if mine are in that category... :eek:

Another Question:

Have you auditioned these speakers in your home on your current system ? Not yet obviously. :rolleyes:
I mean there could be 100's of testimonials but these aren't in your living room.

The Bastanis series is 400W and 600W rated yet 250W with 100dB/W/m would be too powerful ? Hes not saying my amps are too powerful.

Consider many tube amps have higher output resistance than usual which might 'work well' with these speakers.
You can always simulate this by adding a small resistance in series with the cable to see if that improves it. I will give that a hard pass but thank you for the tip.

In any case... one should always audition speakers in their home for at least a week. As I explained in an earlier post, one does not always buy direct from a shop that has a return policy, in fact I havent spent a great deal on any speaker to date, I am a cheap skinflint who does diy, ebay and purchases from friends. The Club-27 will be my most expensive speaker purchase and I would probably be better off selling on rather than paying return postage to the Neth rlands!
Given your response this seems to be the best advise for you.
Thanks for the advice dude.

Those Bastanis look cool. Your 250w amp, if quiet, should be fine. Yes they tick all the boxes that I have compiled over my years of experimenting, if the sales pitch is to be believed and this guy seems to think so, I could be using really foul language posting this link so apologies in advance.... WANING WARNING SUBJECTIVE REVIEW

I think the speakers are likely designed to allow tube amps to perform their best, and many speakers do not work well with some tube amps, in my experience. The reverse is not so true however. Speakers that are amp friendly are just more flexible... they should work fine with solid state. I have dipped my toes into kt88 amps, it was chinese so with the help of the original wilmslow circuit it was copied from, i through away the pcb and built the wilmslow with it but with updates, I love the glow and design of tube amps. I would like to try OTL, transformers are after all what makes a tube amp so speaker dependent, I know OTL means the speaker has to be very friendly.....

I pretty much just have horn speakers so I can play around with different stuff, like tubes or early consumer grade solid state radios, and so on.
I do love the design of the Michell Alectos.

Please dont complain about the wires dangling down from my tv, I hide wires inside walls for a living, AV installer, I just keep telling the wife Its temporary, she is very understanding. :)
 

Helicopter

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:DMy thoughts exactly when I was experimenting with all these designs, the problem with the JX53's, (sorry I said 92s, they were the mids) is they are tweeters not full range, they didnt use a crossover but the range was built into the enclosure design so they didnt go low enough for my OB bass drivers, certainly not low enough to reach the crossover built into the plate amps, I think its 250hz and the enclosure restricted the array to 120hz. They were a match for the JX125's from memory which were used in the Glastonbury's but I never got round to building a crossover for the speaker I created bolting the array on the side of them. I did have a lot of fun....



I guess, but only guess this is what he is alluding too.


I think I am going to find out if mine are in that category... :eek:

Thanks for the advice dude.



I do love the design of the Michell Alectos.

Please dont complain about the wires dangling down from my tv, I hide wires inside walls for a living, AV installer, I just keep telling the wife Its temporary, she is very understanding. :)
Looks nice.
 

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I view horns as acoustical transformers, in the way that electrical ones are. They trade high pressure low excursion air movements at the throat into low pressure high excursion air movements at the mouth, analogous to electrically transforming high current low voltage into low current high voltage.
 
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