audio nirvana super 8

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Hi-newbee here
I wanted to dip my toes in the single driver and SET ocean so I bought some super 8s and built the enclosure that came with the drivers. Horrible shreiks resulted (first from the speakers-then from me). Took a step back and built a TL design of Martin King.. Better, but not good. I am using a Rotel SS amp so I decided to increase the output impedence ala Nelson Pass by adding a parralel resistor to the amp output. Better still but still not good. My questions are:
1. Has anybody had positive experience with Audio Nirvana drivers?
2. I am surprised at the noticable effect of amp output impedence on the sound. Is it possible that "full range drivers" require a low power class A amp in order to sound OK?
3. Am I hopelessly lost without some way to measure the TS parameters? If so, could somebody recommend a suitable low cost way to do measurements?( If I had significant money, I would buy somebodys system and be done with it).
Thanks in advance and have a happy new year.:rolleyes:
 
Use a BSC circuit, that will help significantly. You can size the circuit using the simple Excel worksheet that can be found under my General Speaker Related Articles page. Tweak the parallel resistor value by ear (+/- 1 or 2 ohms) to fine tune. I am using a Rotel RB-1080 200 W amp to power my Lowther designs and it works very well. I would try the circuit before buying a new amp.
 
What Martin said.

Going a little further, there's not much wrong with the AN drivers: they're not as good as the Fostex units, but they're not half bad either, especially for the money. Your problems are likely caused by four separate factors.

Firstly, they're a very low Q unit. A low Q driver has an exceptionally powerful magnet, and a very light cone, so it moves faster than a scalded whippet, which is great. However, you can over-damp it with an amplifier with a high damping factor (causing the bass to vanish). That's why you found noticable sonic differences when you adjusted the output impedence with the series resistor. Low DF amps are the 'natural' match, but are not an automatic requirement, as you found -adding some series resistance to the driver allows you to adjust the damping applied, and will bring some of the bass back up. That's what Martin does: so do I and lots of other people (though I have valves too for horns).

Which brings us to the second issue of baffle-step. As if over-damping didn't clobber the bass badly enough, this raises its head, just to finish you off. ;) Martin has gone into this in great detail in his different articles which I won't bother to repeat here. Suffice to say, the point at which it occurs is determined by the external width of the baffle. A BSC circuit will negate this problem, bringing everything above this point into line with the LF.

Thirdly, the AN Super 8 in particular has a very rapidly rising response indeed. From about 700Hz upward, it goes reaching for the skies. At 15KHz, looking at the rather unclear graph on their site, it's about 15db louder than it is at 700Hz. You're either going to need to listen a fair-way off axis, or a notch-filter to get that down to reasonable levels.

Final point to consider is that of the driver / cabinet combination. Martin's MLTL design is superb. However, he intended it for the Lowther drivers, which according to his measurements have an average Vas of about 45 litres, give or take. It also works with the Fostex FE206/7E units, which have a Vas of about 55 litres. The Super 8, according to the published specs., has a Vas of 95 litres. So despite having a similar Q, this is not really a drop-in replacement for the Fostex or Lowther units -it will need a fair bit more cabinet volume in order to provide the same level of LF response.
 
Well Scott, I figure this is the appropriate thread to talk about this for a change.
I finished the prototype that you and I have been discussing. All I can say is (duyuyuygoogoogaagaa). Ok, seriously. The ANS8 is really VERY good. The horn is truly a spectacullar design. Huge but spectacular. It sort of sticks out into the livingroom. 3 feet of space in to the room that is! Completely worth the imposition however.
A few comments on the ANS8

1. I find this driver (in a proper enclosure) to sound quite a bit better than the 206. I really am glad I took the chance on it, seeing that it cost more than the 206. The mids are warm and concise, the highs are detailed and smooth, the bass I am measuring in room is 35 Hz usable. I am running it off of 6 watts and am very pleased. I would rarely listen at top levels but it is really quite capable of making ones ears bleed at 5 watts.

2. I find this driver requires proper speaker cabling. It is more noticable than on any of the fostex drivers that I use including the 126, 167, 206. I believe this is due to the amazing usable range on the high end, as well as, its ability to go down to bedrock in the bass. There really is NO tweeter required with this driver.

3. This is going to sound wierd but the rising response seems to be A Godsend. Let me tell you why. In room, with most of my other drivers, the hf response is no good if not completely gone off axis. This presents a problem if others are here listening with me. Unless of course I used a super tweeter, which seems to clear up most of the problems. Now, I don't mind listening off axis as the sweet spot is still sweet, it is just much wider. As you see this makes the sweet spot or at least the listenable area for the speaker much less pinpoint which in turn makes the speaker much more enjoyable to others that might be sitting next to me or close by.

4. This is completely and utterly subjective but, this driver seems much more balanced. The 206 tends to sound a bit shreaky or shouty or whatever you want to call it, which only gets worse as it grows louder. Classical music really demonstrates this well. The ANS8 on the other hand sounds much more balanced and if this makes any sense, balanced in it's articulation and assembly of frequency groups.

All of that said. One thought on other's experiences with this driver. I believe the FS of this driver to be 37 Hz. Unlike the Fostex and the Lowther. I cannot say this for certain until I break them in. I will measure them again at that point and post my findings. Now, why is this important? Well, others have placed this driver in horns designed for the afformentioned drivers. These horn's flare constants are usually 45-55 Hz. In my experience with simulating this driver, it really does require a horn thats flare constant is 37 Hz. To do otherwise seems to rob this driver of it's ability to sing. Just my two cents.

One other note. I have noticed the mid-highs to be a touch papery. This has reduced noticably during their break in and I feel that it will most likely disappear as the cones break in. Not too important a thought but one I thought worth mentioning.

This may sound a bit odd as well, but, I feel that they sound nearly as good as the 208 Sigma. Not as good mind you but in the ball park. More balanced is what comes to mind but not quite as articulate or clean. Granted, I have only listened to the 208 a couple of times.

Tom
 
Ah. Horns. Bigger is better. :D

I've heard the Standard 8s -not bad, not as good as the 206, but I wasn't complaining. I quite like the aesthetics of the heavier surround too. Not a bad unit at all -not up to the 206/7, but not far off. Be interesting to hear the Super8s at some point.

FWIW, the 206's I've come across have matched the manufacturers 39Hz Fs claims. Got a long path double horn coming for them with Dave in the next few weeks which should be interesting. I've finally got some time on my hands so I'll be able to run a mathcad sim of your box. Back later.

Scott
 
Scottmoose said:
Ah. Horns. Bigger is better. :D

I've heard the Standard 8s -not bad, not as good as the 206, but I wasn't complaining. I quite like the aesthetics of the heavier surround too. Not a bad unit at all -not up to the 206/7, but not far off. Be interesting to hear the Super8s at some point.

FWIW, the 206's I've come across have matched the manufacturers 39Hz Fs claims. Got a long path double horn coming for them with Dave in the next few weeks which should be interesting. I've finally got some time on my hands so I'll be able to run a mathcad sim of your box. Back later.

Scott


Ah, well that being the case, I suppose then what I was getting at was that horns always tend to be designed for 50 Hz etc. I guess size is the reason. A 37 Hz horn is much much bigger than the corresponding 50 Hz horn.

I look forward to seeing the long path double!

As for hearing the ANS8, I would say stop on by but I think I live a few thousand miles from you. (Washinton, D.C.) Ah well.


Tom
 
The one and only
Joined 2001
Paid Member
cascadeguy said:
I am using a Rotel SS amp so I decided to increase the output impedence ala Nelson Pass by adding a parralel resistor to the amp output. Better still but still not good.

To increase the output impedance seen by the driver, you would
place the resistor in series with the amplifier output, not
parallel.

My experience with the super 8's has been quite good, although
I haven't had the time to write up my observations.

Knowing the drivers parameters is helpful, but there is no
substitute for trying different things and seeing what you
get.

:cool:
 
Hi guys,

Tom,

Well Scott, I figure this is the appropriate thread to talk about this for a change.I finished the prototype that you and I have been discussing. All I can say is (duyuyuygoogoogaagaa). Ok, seriously. The ANS8 is really VERY good. The horn is truly a spectacullar design. Huge but spectacular. It sort of sticks out into the livingroom. 3 feet of space in to the room that is!

What enclosure would this be?
My little brother bought this AN8 (he never listens to his brother
:( ) and he's not pleased with the recommended vented box.
He is willing to try my modded Autograph this time :D
but he is open to any recommendation.

Thanks,
M
 
I'm not surprised about that. The standard boxes are rubbish.

Max -once I've got a couple of other cabinets designed, I'll probably be looking into designing a box in the style of the Westminster Royal HE (side mouths) but designed from the ground up in MathCad. I was toying with the idea, but I've got a few box designs on the go at present, so I had to put the concept on hold for a while.
 
Dear Scott,

Max -once I've got a couple of other cabinets designed, I'll probably be looking into designing a box in the style of the Westminster Royal HE (side mouths) but designed from the ground up in MathCad.

Excellent...but, hey didn't you like mine? :D

I'm fatigued from recommending front and rear "horn" loaded enclosures for AN drivers :xeye:
No need to add any filter as the enclosure complements the climbing response of the driver and the perceived frequency spectrum is well balanced. One of the pitfalls would be possible interaction between HF cone/fase plug and front horn.

(and WAF, for refrigerator sized "box" :D )

Cascadeguy, sensitivity increases around +6db in a proper enclosure, so party level SPL with virtually no cone movement :cool: for Valve amps... and fast, articulated bass.

Cheers,
M
 
Administrator
Joined 2004
Paid Member
Strange about the designs for the Audio Nirvana and other drivers on the Common Sense site. The box designs don't seem right to me.

I guy I built some amps for bought a pair of P.Audio coax from them. I simed the cab they suggest and it looked super bass shy. Warned the guy, he wrote them and they said they don't quote specs on their stuff. Just build them and they will sound good. Hmmm...

Never did hear them. Got to look the guy up and have a listen. Seemed odd to me.
 
Yeah, well. Thee and me clearly share the same views on these boxes. Modified, the 2.5 looks vaguely acceptable with the AN10in unit, but it really does need the mods. Stick two 8in drivers into the cab., in parallel, and they're better, but still not anything I'd consider without heavy modifications. The fact that they refuse to supply anechoic or in-room response data, and load their site up with testimonials always sets alarm-bells ringing in my mind. I dare say they might suit some people, and in some cases, they're not that bad, but I'd rather design something of my own.
 
Scottmoose said:
Yeah, well. Thee and me clearly share the same views on these boxes. Modified, the 2.5 looks vaguely acceptable with the AN10in unit, but it really does need the mods. Stick two 8in drivers into the cab., in parallel, and they're better, but still not anything I'd consider without heavy modifications. The fact that they refuse to supply anechoic or in-room response data, and load their site up with testimonials always sets alarm-bells ringing in my mind. I dare say they might suit some people, and in some cases, they're not that bad, but I'd rather design something of my own.


You know, I had a discussion with the guy that sold me the ANS8's. He was really quite negative and literally downed every horn or transmission line ever designed. I couldn't believe what I was hearing. He said "there is no such thing as a "good" sounding horn. I argued with him for a bit but there was no convincing the guy. He claimed he had heard many horns from the Klipsch variety to the Lowther horn variety. Basically said the onl reason people build horns is to "impress there friends". Which struck me as odd as I don't know many people that build any speakers for that reason. I am sure there are some but in the end I suppose there designs aren't worth much anyway. Ah well. I am really glad that I took the chance and bought the ANS8's though, regardless of the guy selling them. They truly are a fantastic driver. Oops, I am editing this post again. I forgot to mention what I started writing the post to say. I asked him about his design and he couldn't tell me or didn't want to tell me what he was trying to achieve with it. He wouldn't telll m if he thought it was a TL but he did keep calling it a bass reflex. I have simmed the box and I will tell you, if it is a bass reflex, I have no clue as to how it was designed because it looksmore like a shot in the dark design than anything. :)

Tom
 
They work like badly designed MLTLs.

Background to them is weird. My best guess is this: I've run a few MathCad sims of the different cabinets, mostly the 2.5. and the larger ones look to have been designed to take 2 drivers, at least in terms of internal volume. But with one driver, an no mods. to the cabinet, you're in deep trouble. The AN10 is better (solo) in the 2.5. In fact, with a differently placed, and completely re-sized vent, it should be pretty decent, assuming the cabinet is damped properly.

What you say about his remarks tally with what I've heard from other people, and to me confirms he doesn't have the faintest idea about cabinet design, or the objectives therein. I did once wonder idly, given the CSA of the vent, if he was aiming for a design based upon the original 1934 bass reflex patent, rather than one of the later T/S alignments. But I scotched that idea: it's not big enough. It doesn't match with the transitional period between the reflex patent and the emergence of T/S alignments either. And certainly not any T/S alignment I've ever seen.

So aside from volume, I would say your right -shot in the dark, with no real objective discernable. I will revise my views on these cabinets only if I see some evidence to the contrary that I can swallow without gagging. I refuse to accept unsubstantiated claims of the nature they come out with. Especially considering MathCad shows abominable technical performance at worst, extremely mediocre at best. And I long ago learned to trust the accuracy of Martin's worksheets. It's downright frightening what they can do.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.