I would look more for something like the EOS by Trafomatic audio. It has specification closer to what is realistically achievable and conservative for the KT120.
CFB (5db or more) + 8 db of GNF in standard 5k OT can drive your ATC impedance without stress. Looks like they can eat 100 watts easily.
CFB (5db or more) + 8 db of GNF in standard 5k OT can drive your ATC impedance without stress. Looks like they can eat 100 watts easily.
Dave
Thank you. This simple explanation was very helpful to me in understanding the problem at work here. I now see what you are getting at.
Equating measurements to listening values, it is odd that these highly rated speakers are not known for their boomy bass. In contrast, they are well reputed by most professional reviewers - and there have been many - to have tight, fast and punchy bass.
I was thinking that this outcome was simply because all of the reviewers used amps that had sufficient damping to deal with this peak? But then I recall many of the reviewers used amps that were not particularly "grunty" and were often deemed to need more power - but the ATC SCM19 still sounded fantastic!
I'm keen to understand this apparent anomaly and your view on what type of amp would be best.
At GBP9,000 - or there about - I would be expecting a bit more from the TRAFOMATIC EOS. 😀
She looks a treat, but I need to keep this discussion around real-world pricing. To me, that means $US1,300 - $US2,600 or there abouts.
They are likely using low output impedance amps.
Here is an example of the “same” box after you consider what happens if the amp has higher output impedance.
http://wodendesign.com/downloads/King-of-Swingers.pdf
It clearly shows what happens to the box volume when you take amplifier output impedance into account.
For those speakers you need an amplifier with lower output impedance. Or add woofers, bi-amp with XO point at least an octave above the resonance. Since the impedance is fairly flat, and where it isn’t, is complementary to the FR, that the output impedance won’t matter and the amp would be suitable.
But contected to the 4Ω tap on a typical PP amp with feedback the speakers should be fine.
dave
The graph bellow shows how this tube in classAB can genarate 3rd order harmonics of opposite phase . This why I advise you to buy it but apply 6db extra NFB . The output impedance by this gets halved to 1.25 ohms . Apply 1.25 ohms resistor to your speakers and hear by how much you loose punch and get boomy .
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Yes, you need to increase prices then naive people will assume that they are getting something good. People have been conditioned to expect to pay high prices for audio, and want to be able to brag to their friends that their ears and earning abilities are suitable for this.nigelwright7557 said:
Reactive current is a waste, but it is a necessary waste if the speaker requires it. The speaker requires it whenever it has a non-resistive impedance. A good amp can provide it, by having low output impedance and good current drive capability. This is not "word salad" but simple audio engineering.pblix said:
Taming the speaker bass resonance is a matter of low output impedance. This has nothing whatsoever to do with maximum power or 'gruntiness' (whatever that is).SONDEKNZ said:
I think the atc would be compromised with a 35 watt tube amp...
I would definitely drive the atc with some good transistor amp.
If you look at ATCs drivers specifications it is clear that they were not designed for easy to drive and sensitivity.
I would definitely drive the atc with some good transistor amp.
If you look at ATCs drivers specifications it is clear that they were not designed for easy to drive and sensitivity.
Sorry to dredge up an old post out of this thread, but I think I noticed something. In this shot...
...it looks like the toroid power transformer is mounted so that the wires from it face out towards the tubes/valves. Toroid transformers have appreciable leakage currents where the wiring exits the coil. Unfortunately, the layout is such that these leakage currents are facing directly into the audio circuitry. Wouldn't it be more desirable to have the toroid PT facing 180 degrees the other way, with the wiring exiting out towards the back panel of the chassis--away from the audio circuitry?
...it looks like the toroid power transformer is mounted so that the wires from it face out towards the tubes/valves. Toroid transformers have appreciable leakage currents where the wiring exits the coil. Unfortunately, the layout is such that these leakage currents are facing directly into the audio circuitry. Wouldn't it be more desirable to have the toroid PT facing 180 degrees the other way, with the wiring exiting out towards the back panel of the chassis--away from the audio circuitry?
Noise levels are down in the specifications. and your picture is taking too much space
If you bought the parts to build it diy, you would end up with more than the sale price.
If you bought the parts to build it diy, you would end up with more than the sale price.
Not sure I'd want to be boring holes into the back of $4k speakers, but I understand what you're getting at. As the speakers in question aren't exactly bass monsters, a little added warmth might not be a bad thing.
jeff
This is often the case but there are counterexamples where the box or driver provides the necessary damping. In these cases, if you use a low output impedance amp, the system becomes overdamped and sounds lean.
dave
Well, it seems that by all accounts, the TRANSCENDENT SOUND BRUISER is no match for the ATC SCM19 speaker load.
With this in mind, I'd like to explore the other ATC model on our short list: the ATC SCM11. Our next home will be an apartment, so the SMC11 may be the better choice for a smaller listening room anyway.
Specs for both 19 and 11 look almost identical, with the 11 having a lesser 11-Litre (Sealed Box also) cabinet and reputed to be a slightly easier load.
So the question becomes: Would the TRANSCENDENT SOUND BRUISER comfortably drive the ATC SCM11?
We appreciate any expert feedback.
Here's a bit more detail on the ATC SCM11...
With this in mind, I'd like to explore the other ATC model on our short list: the ATC SCM11. Our next home will be an apartment, so the SMC11 may be the better choice for a smaller listening room anyway.
Specs for both 19 and 11 look almost identical, with the 11 having a lesser 11-Litre (Sealed Box also) cabinet and reputed to be a slightly easier load.
So the question becomes: Would the TRANSCENDENT SOUND BRUISER comfortably drive the ATC SCM11?
We appreciate any expert feedback.
Here's a bit more detail on the ATC SCM11...
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![Stereophile Fig. 1 ATC SCM11, Electrical Impedance [solid] and Phase [Dashed].jpg](/community/data/attachments/716/716427-aa80977e77e409e254692c9ca7f833f9.jpg?hash=qoCXfnfkCe)
For convenience, here's a refresh of the essentials of the TRANSCENDENT SOUND BRUISER.
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No.
That huge impedance bump at the crossover would be a big bump in the FR right there. And it won’t do anything for the bass.
dave
The only thing that is limiti g you is the output impedance. None of the other stuff is of much importance.
A suitable speaker for the beast will have very flat impedanceor a slight rise at the ends that helps extend the FR.
dave
I would not buy anything based on specifications... speakers or amps or sources
All atc drivers are designed for high current power amplifier transistors.
All atc drivers are designed for high current power amplifier transistors.
35WPC in an apartment is a lot, don't you think? We're talking tube-watts, so a couple of watts and your neighbors will most likely still bang on the walls at full tilt. I'd go with a Tubelab SSE. Should be able to deliver exactly what you need.
After 8 years I finally had a neighbour complain to me about the SPL. This came about from full volume testing of my 6P45S monoblocs... 112W RMS in a 32sq-m apartment... Time to move to the country 😀
Also, for 1000$, you can build a pair of these monoblocs without tubes, and they will destroy that Transcendent Bruiser. 112WPC @ 30Hz in triode!
Also, for 1000$, you can build a pair of these monoblocs without tubes, and they will destroy that Transcendent Bruiser. 112WPC @ 30Hz in triode!
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