Frank listens to mini monitors on chip amps and talk about 120db capability and disappointments at hi -fi shows , there is a big disconnect in what he says and percieve and i have said on many occasions that the linesource is not the only speaker i have( large 3 way monitors) and on the others i have used as small as 30w SET amplifiers as well as many others SS stuff.
Also if you look closely at quite a few speakers on the market , magico Q7 for example its ZMin , is actually 1.2 ohm. , wilson is very similar , the ribbon actual represents a pure resistor load to the amplifier. My current setup is similar to a genesis 1.2 or a Infinity IRS type system , except those are not ribbons but planar magnetic. MLS. Electrostats are also 1 ohm , but in the high frequency only , the load is not that unusual , unless you using a small 2 way or single driver type VC speaker ...
Its a big problem , it will have poor sonics by changing the tonal balance of the speaker and for 17k thats not acceptable to me , put a proper damn Transformer in the amp , bryston has always done this , i had the same issues with my 4Bst in the past , not going there again...
Also if you look closely at quite a few speakers on the market , magico Q7 for example its ZMin , is actually 1.2 ohm. , wilson is very similar , the ribbon actual represents a pure resistor load to the amplifier. My current setup is similar to a genesis 1.2 or a Infinity IRS type system , except those are not ribbons but planar magnetic. MLS. Electrostats are also 1 ohm , but in the high frequency only , the load is not that unusual , unless you using a small 2 way or single driver type VC speaker ...
Here I see a possible dichotomy. After losing those 5 dBW, how many dBW are still left over?
Because if enough is left over to cover all your realistic needs worst case, what do you care?
You won't get far in this world by being a perfectionist, Wayne, or you can be that, but at an even more outrageous price point. But you definitely can't have great sex and remain innocent.
Regarding the Brystones, I don't think it's the PSU so much as that by the time you get to 1 Ohm loads, you definitely have a megaproblem with sheer heat and current dissipation in the output stage. By the time you get an average of say 50W dissipation into 1 Ohm loads, bring along a frying pan and fry some steaks over the heat sinks. Or dedicate a whole air con machine just to cool off your amps placed in a dedicated chamber. Like big mainframe machines. With 1 Ohm peaks of 100 Watts on a protracted basis, I imagine your amp will be drawing well over 1 kVA from the mains.
Its a big problem , it will have poor sonics by changing the tonal balance of the speaker and for 17k thats not acceptable to me , put a proper damn Transformer in the amp , bryston has always done this , i had the same issues with my 4Bst in the past , not going there again...
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This is a problem of web communication, listening can be nothing but virtual in a web space. And so many subjective impressions and words. To me, small PC plastic speaker boxes are also insufficient. Each to his own. Chipamps may be enough for small plastic boxes, no need of power or high current drive there.
I agree that the impedance can DIP for a short while to as low as 1.2 Ohms, Apogees did that in their time, and the Dahlquist was no rose either. But their OVERALL average impedance was around 3-4 Ohms.
My own speakers have a nominal impedance of 8 Ohms, but in one place they do dip down to 6.5 Ohms, and elsewhere they rise to about 11 Ohms. That's why it's called the impedance modulus, it varies.
Bryston is a commercial enterprise, so they need to rule themselves according to what the MAJORITY of their buyers want to own. I feel reasonaly certain that most Brystone amps will drive the likes of Wilson very well overall. Do I really need to remind you that most Hollywood sound studios use Bryston ampflification? That doesn't happen by sheer chance, you know, it takes many years to get there and dropping out is a matter of just one wrong product. As others have already experienced (e.g. Micromega of France).
As for maximum possible SPL, I agree that's a major concern, because that defines our usable dynamic range. I would be hard pressed to find a small speaker capable of surpassing say 107 dB SPL at 1 m, and that in peaks only. I know about it because using the manufacturer's data, it turns out that my own speakers can theoretically reach just above 114 dB SPL at 1 m, but I would say that since SPL delivery is anything but a linear function, 112 dB is more realistic. If I take a chance and decide that they can accept short term power peaks greater than 150W (as decared by Son Audax), possibly 1 or 2 dB more, but that's just possibly.
On the other hand, I am only too well aware at what far less power output does in my room, bad things, like rattling of widow panes. So I regard anything above that as a welcome reserve I can enjoy only with some selected extra deep bass sounds, like Bach's organ works, kick bass drum, tympani, and deep down piano notes. Not for loudness, but for the realism of portrayal. My speakers do go down to 36 Hz at -3 dB, but to actually do so and keep the expected tonal balance, they need a VERY good power delivery feed. Fortunately, I own two amps which can do that without undue stress, the Karan integrated (nominally 180W/8 Ohms) and the H/K Citation (nominally 100W/8 Ohms, but it will short term peak at around 160W/8 Ohms).
I've already commented on small 2 way speakers.
As for power amps, anything to do with the PSU is serious business, much like any fiddling with our heart is serious, sometimes deadly serious, business. Not to be fooled around with. The exact wrong place to start saving.
That is a good question for the speaker manufacturers.
I suspect one of the reasons is that the vast majority of them buy in their drivers, and are therefore limited in choice. Sometimes, they might insist on using a particular driver because it's an objetively good driver, but marrying it with the rest of loudpeaker model can become tricky.
Long gone are the days when many serious speaker manufacturers had their own drivers either made in house, or had someone make it for them as custom models.
And the world market for drivers is shrinking.
Dan,
Unfortunately to build large SOTA speakers , Imo, it's impossible to do so and not have the impedance go below 4 ohms( unless bi-amped) and no there are quite a few amps that will do so comfortably to 2 ohms, the list is shorter at 1 and funny enuff quite a few of the 80's designed amplfiers do , lesser today and mostly because of tons of protection stuff .
A friend has the same issues driving his MLS electrostatics , you have to stick to the approved brands .
My speakers are a leftover prototype that was being developed by the speaker company i was involved with many moons ago, i had them revised and waiting for the updated Larger version because i had expanded them. They are similar in looks and setup to the gen 1.2 but different in application , no servo woofer column. My bass columns uses two 15 inch woofers per/ch in a push pull loaded config dissipating midroom for improved bass dispersions and the panel uses an 8 inch bass/midbass coupler which is adjusted to blend the panels seamlessly to the sub columns and to the direct drive ribbons (mid/twt) this mid tweeter setup is a purely resistive 1 ohm load , its currently bi-amped.
I have a smaller version without the sub column and shorter in height and that is what i'm currently using until i get back the larger version with the updates, thst one is driven by a single amp...
Unfortunately to build large SOTA speakers , Imo, it's impossible to do so and not have the impedance go below 4 ohms( unless bi-amped) and no there are quite a few amps that will do so comfortably to 2 ohms, the list is shorter at 1 and funny enuff quite a few of the 80's designed amplfiers do , lesser today and mostly because of tons of protection stuff .
A friend has the same issues driving his MLS electrostatics , you have to stick to the approved brands .
My speakers are a leftover prototype that was being developed by the speaker company i was involved with many moons ago, i had them revised and waiting for the updated Larger version because i had expanded them. They are similar in looks and setup to the gen 1.2 but different in application , no servo woofer column. My bass columns uses two 15 inch woofers per/ch in a push pull loaded config dissipating midroom for improved bass dispersions and the panel uses an 8 inch bass/midbass coupler which is adjusted to blend the panels seamlessly to the sub columns and to the direct drive ribbons (mid/twt) this mid tweeter setup is a purely resistive 1 ohm load , its currently bi-amped.
I have a smaller version without the sub column and shorter in height and that is what i'm currently using until i get back the larger version with the updates, thst one is driven by a single amp...
Wayne, you have commented at least a couple of times about Perreaux 2150 being 'weak'.
Perhaps this assertion is unfair, given that these amps were never designed for sub 2 ohm loads.....your speaker load is pretty unusual.
In defense of the 6000B, plenty of shows I have run a rack of 4 of these amps (3 for FOH + 1 for FB), and pulled the best live sound that I have ever heard, period....lot's of good comments from audience members also.
I do have misgivings about pcb layout and internal wiring, but physical construction and layout is top notch, even ahead of it's time.
Dan.
Perhaps this assertion is unfair, given that these amps were never designed for sub 2 ohm loads.....your speaker load is pretty unusual.
In defense of the 6000B, plenty of shows I have run a rack of 4 of these amps (3 for FOH + 1 for FB), and pulled the best live sound that I have ever heard, period....lot's of good comments from audience members also.
I do have misgivings about pcb layout and internal wiring, but physical construction and layout is top notch, even ahead of it's time.
Dan.
Is the 6000B a perreaux..?
I will add that at all times my pr of perreaux's were bettered by a pr of adcoms 555 , which will play the ribbons without issue , in my books anything not able to better the lowly adcoms are a joke at best Dan..
With all the other stuff i currently have and have had , my adcoms are my stalwart door stops and cutoff point, anything brought in has to better them or out they go , that list has gotten pretty long over the years ...
Why so ?....low impedance ribbons are the only solution ?...
Cronyism ?, lol.
Some pics might be interesting.
Xmas
to you also.Dan.
Your recollection is poor - dCS does not use 'a noisy chip'. It uses quite a few logic gates (latches or flip-flops most likely) as its DAC elements. The modulation noise results from the use of truncation within a feedback loop, nothing to do with 'a noisy chip'.
If you provide chapter and verse for your claim regarding what I said, I'll address it. OTOH if you just wanna complain (as here), I'll ignore it
D,
I used to sell Brystons to studios( in the 90's) so yes i know, we supplied them along with our studio monitors at the time, they were well built and very very reliable with a 10yr warranty,
So ....?
I didnt say they were not good , i said they dont work for me , my personal , i had better for that and the Brystons were a big improvement over what most studios were using back then , those dreadful give SS a bad rap Crowns ...
I used to sell Brystons to studios( in the 90's) so yes i know, we supplied them along with our studio monitors at the time, they were well built and very very reliable with a 10yr warranty,
So ....?
I didnt say they were not good , i said they dont work for me , my personal , i had better for that and the Brystons were a big improvement over what most studios were using back then , those dreadful give SS a bad rap Crowns ...
Why so ?....low impedance ribbons are the only solution ?...
Cronyism ?, lol.
Some pics might be interesting.
Xmas
Dan.
No, Magico , Martin logan and Wilson to name a few have speakers with Zmin in the 1-2 ohm range, there are others.
I choose to go with ribbons because of the purity of the sound and a large linesource For the effortlessness it brings to the table. Point source speakers dont work for me on large scale recordings ....
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Yes there is a 6000B (300/8/ch, pretty much double into 4 ohms).
All the FOH amps were 4 ohm loaded, and not a very big room/venue...pretty serious SPL generated.
Rock/Blues, uber professional band, really great fun when the mix is sitting right.
The 2150 is rated at 200/8/ch, and 10,000 uF/rail...maybe a bit light on for your application...maybe going into current limit ?.I will add that at all times my pr of Perreaux's were bettered by a pr of Adcoms 555 , which will play the ribbons without issue , in my books anything not able to better the lowly Adcoms are a joke at best Dan..
With more 'normal' speakers, and some minor tweaking, the 2150 is a good amp for most users....clean, clear, precise, with no real sound of it's own.
Not surprisingly
Dan.
Ok agreed.....the Genesis 1.1 had/has that huge effortless dynamics/purity in the mid/highs (AR 150??), and on Hendrix and The Who, low bass that shakes one's vision....in a big room, seriously impressive.
Too bad about the neighbours !.
Dan.
Yes if not for the neighbors i would have used 18's instead ..
To paraphrase Steppenwolf's song: "God damn the neighbor man ..."
The spec's in the user manual tell you exactly what it was designed to do:The 2150 is rated at 200/8/ch, and 10,000 uF/rail...maybe a bit light on for your application...maybe going into current limit ?.
With more 'normal' speakers, and some minor tweaking, the 2150 is a good amp for most users....clean, clear, precise, with no real sound of it's own.
Not surprisingly
Dan.
* 200W continuous, both channels driven into 8R, 20Hz to 20,000Hz , 0.009% distortion from 0.25W to rated power
* Amp saturation: 700W per channel into 8R
* Voltage swing: 164V p-p
* Current output: 10A continuous, fuse limited
Voltage drive, not current delivery ...
These days, in the manufacturer's glossies, how many tell this level of detail?
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