Don't try too hard to bring back 1960's Vox Supreme style speaker stands?
Call the bellhop...
Well.... in other news.... I have 2 working drivers installed and took another indoor measurement at 16"
Most of this work has been to appease my peers, not that I am not doing it for myself, as it is myself who want to appease you. I'm sure @gedlee can find some things to point out... I am interested in hearing them. One day I will make it out doors for a measurement but for now this is what I have. There is no damping material used in the slot or inside the box yet. This is the 15" driver PPRSL as I've dubbed it. I think I can improve the FR more, yet but this is a good start considering the challenges of slot loaded woofers.
It's disappointing to see an education the forum has given squandered for a machine that isn't telling fact from fiction.
But to presume to educate us via this machine is simply insulting.
In what universe is a response of +/- 10dB from 200 to 600Hz a "good start"?
Why did you decide to ruin the midrange response of the two 15" by putting them in a slot ?
A quote is a quote, but it will definitely be worth noting when a quote is derived from AI.... in DeepSeeks defense, I do not normally use it nor was it prompted which should expectedly lower the quality of the experience... I didn't expect it to make up fake quotes from AES, sorry... I wouldn't say that foul play was had on my side... the AI did apologize if that makes you feel any better.
I don't think that my education has been "spoiled" by AI, all it has done is cause me to have more questions so as long as I seek validation from real professional, as I've done here in this thread for years now, it should work out.
We have not touched on the topics of Damping Force and Damping Factor in this thread. I try to at least do some type of research before I come to the thread. I have a better understanding of Back Emf now thanks to AI.
The rest of the AI generated content has been designated as such.
I wouldn't wait to see a question mark to correct erroneous statement.
I don't think that my education has been "spoiled" by AI, all it has done is cause me to have more questions so as long as I seek validation from real professional, as I've done here in this thread for years now, it should work out.
We have not touched on the topics of Damping Force and Damping Factor in this thread. I try to at least do some type of research before I come to the thread. I have a better understanding of Back Emf now thanks to AI.
The rest of the AI generated content has been designated as such.
I wouldn't wait to see a question mark to correct erroneous statement.
It makes me feel that there is little understanding of the nature of AI...
In the past you've indicated that posting incorrect statements is effective at eliciting responses. This confrontational style is already a source of consternation and fortunately for the continuation of the thread, it has tended to drive away some of the contributors.
In this age of AI it takes on new meaning and greater consequences.
Well first of all, the response drops -10db from 200 to 600 hertz.... and, its a smooth transition at that. I don't think there is anything here that would have trouble being sculpted by EQ, unlike the sharp null in the response of the first slot design. Considering the xover will never be over 300hz I think it is something to work with. Lets keep it in context by the way. I haven't seen a slot loaded woofer with a response better than this. There no large peaks/nulls that stop one from sculpting the response
Looking at response of the first slot design, I'd say I did good. Those nulls did not help anything, so as long as the 18" PPRSL plays as nice as the 15", I'll be happy.
I was using DeepSeek to cross reference Grok. Grok was making some silly mistakes i'm using another AI to cross reference it usually creates argument they both go back-and-forth... hopefully catching each other's silly mistakes. At the end of the day, I personally would only consider it a tool to lead to more questions to be verified by more legitimate sources.
agreed. Fortunately the mainstay of information has been covered already. I went off into an AI bing on resistance versus wiring topology. I think I landed on solid ground.... no?
Damping Factor offsets the lack of back emf power had due to higher resistant topology.
I think I see where you're coming from and unless I'm mistaken, I'd disagree with your conclusion.
Are you familiar with the Miller effect? Your AI model might not be able to make the connection I'm implying here, but someone who understands the connection between an impedance and how you approach acting upon it, might.
Well The miller effect is a new concept for me... I'll research it. What I think I know is that a drivers Back Emf is a figure that we can look at as voltage generated by movement. The voltage generated is separate from the circuits resistance. As resistance increases (series wiring for example) the voltage results in less power, the damping factor is higher for higher resistance topology in order to counter act this, and retain a uniform damping character across different levels power of back emf due to the influence of resistance.
If thats not how it works then maybe someone can elaborate on how it truly works...
Otherwise AI isnt shy;
At 11:05 PM EDT, Saturday, July 05, 2025, the Miller effect plays a nuanced role in damping for your four Acoustic Elegance 18H+ and NMB 600 woofers (32Ω series load, adjusted 88.5 dB/1W/1m at 30 Hz) driven by a Crown CTs 3000 amplifier, though its impact is more indirect in loudspeaker systems compared to electronics. Let’s explore this:
Miller Effect Overview
Role in Damping
Impact on Perception
The Miller effect subtly affects damping at high frequencies, minimally impacting your 30 Hz focus but worth DSP tuning. (19 words)
If thats not how it works then maybe someone can elaborate on how it truly works...
Otherwise AI isnt shy;
At 11:05 PM EDT, Saturday, July 05, 2025, the Miller effect plays a nuanced role in damping for your four Acoustic Elegance 18H+ and NMB 600 woofers (32Ω series load, adjusted 88.5 dB/1W/1m at 30 Hz) driven by a Crown CTs 3000 amplifier, though its impact is more indirect in loudspeaker systems compared to electronics. Let’s explore this:
Miller Effect Overview
- Definition: The Miller effect refers to the increase in effective input capacitance of an inverting amplifier due to the feedback capacitance between input and output, amplifying the capacitance by a factor of (1 + gain). In audio amplifiers, this typically applies to the output stage transistors or op-amps.
- Context: In your setup, it affects the amplifier’s output impedance and frequency response, influencing how it interacts with the speaker’s back-EMF.
Role in Damping
- Amplifier Output Impedance:
- The Miller effect increases the effective capacitance at the amp’s output, slightly raising ( Z_{\text{out}} ) (e.g., from 0.1Ω to a frequency-dependent value). This reduces the damping factor (DF = ( \frac{R_{\text{load}}}{Z_{\text{out}}} )), which is 320 (series), 20 (parallel), and 80 (series-parallel) in your case.
- Impact: A higher ( Z_{\text{out}} ) at high frequencies weakens the amp’s ability to damp back-EMF, potentially causing transient overshoot, especially at 115 dB/30Hz peaks.
- Frequency Dependence:
- The Miller effect is most significant at higher frequencies where capacitance reactance (( X_C = \frac{1}{2\pi f C} )) decreases. At 30 Hz, the effect is minimal (e.g., ( X_C ) is large), but it grows above 100 Hz, affecting damping consistency across your woofer’s range.
- Perception: Subtle roll-off or phase shift at higher frequencies may soften perceived treble clarity, though your 30 Hz focus sees little impact.
- Interaction with R_loop:
- Your ( R_{\text{loop}} ) values (56Ω series, 3.5Ω parallel, 14Ω series-parallel) dominate ( I_{\text{damp}} ) (0.241A, 3.86A, 1.93A), but the Miller effect modifies the amp’s response to back-EMF. In series (high ( R_{\text{loop}} )), the effect is less noticeable due to low current, while parallel (low ( R_{\text{loop}} )) may amplify transient errors.
- Mitigation:
- The CTs 3000’s high DF (>3000 at 10-100 Hz) and robust design likely minimize Miller effect influence at 30 Hz. Using DSP to flatten response can further compensate.
Impact on Perception
- At 115 dB/30Hz, the Miller effect’s damping impact is negligible, but at higher frequencies, it may slightly blur transients (5-10% perceived softening) in parallel due to lower DF. Series’ high DF counters this better.
The Miller effect subtly affects damping at high frequencies, minimally impacting your 30 Hz focus but worth DSP tuning. (19 words)
The cold, pointy pencil is only used to write words with an even number of letters.
You suggest that a series connected driver produces a backEMF which then encounters the impedance of the other driver as it seeks to pass current through the short circuit of the amplifier output. You suggest that this affects damping, but that it balances out due to the relative levels of this load shared between the drivers.
During this time, what is the other driver doing?
You suggest that a series connected driver produces a backEMF which then encounters the impedance of the other driver as it seeks to pass current through the short circuit of the amplifier output. You suggest that this affects damping, but that it balances out due to the relative levels of this load shared between the drivers.
During this time, what is the other driver doing?
I am saying that for back emf to reach to amplifier it has to travel through resistance of the circuit. X amount of voltage at 2ohms or 32ohms results in different power. Damping Factor adjust according to the deficit of power due to circuit resistance.
Have you changed the question now? Are you talking about the damping of one driver of a series pair in the presence of the second driver, like here...
If we're still talking about the first, what is the other driver of a series connected pair doing while the first is producing the backEMF?
or are you now talking about the relatively insignificant overall damping factor?
If we're still talking about the first, what is the other driver of a series connected pair doing while the first is producing the backEMF?
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I've always been talking about how back emf is treated by the amplifier.... that fake quote from AI lying to me.... who knows whats going on... I never expected AI to pass fictional quotes as real AES quotes (lol) so I was putting it out there like hey guys look at this.... wiring typology doesn't change qes... If one driver is creating back emf so is the other one, on the same circuit??? The resistance in the loop affects each the same? Practically speaking?