SpicyTL - Transmission Line Simulation Model

HR looks simpler to use.

If the TL is starting from the back of the driver, then use the Nd function and fill out S1-S2 and L12.

If you want to move the driver down the line, then use the OD function and fill out S1-S2, L12, S2-S3, and L23. Go to the Loud Speaker Wizard to slide the driver up or down the line until you get the response you want.
HR is an excellent tool and practically indispensable for anyone looking to effectively design horn-loaded systems. However, SpicyTL was specifically conceived for transmission lines and offers features tailored to this type of design.

The LTspice interface, on which SpicyTL is based, is simple and intuitive, allowing users to achieve a high level of confidence in a short amount of time, even for those with no prior experience.

If we exclude more advanced and costly solutions, such as Comsol, SpicyTL is one of the few tools capable of simulating the behavior of a duct partially filled with damping material, while also providing significant flexibility in modeling the material itself.

That said, I fully understand that everyone has their own preferences, and I appreciate your contribution to the discussion. However, please note that this thread is dedicated to supporting SpicyTL. It has been downloaded by thousands of people, including industry-leading companies, and this space is here to support those who use it or are interested in learning more about it.
 
The only project truly worth mentioning is the Ikigai; mainly thanks to the Eikona2, which is an absolutely extraordinary speaker.
Used as a full-range loudspeaker, the Eikona driver has some quirks. Was its rising top end attenuated somewhat in the Ikigai design? If not, that distinct natural sound colouration would seem to have biased the results of any listening tests. Overall, this relatively small driver seems more suited to a compact bass reflex enclosure than a complex transmission line design, albeit the latter will result in a relatively inert enclosure from a panel vibration perspective. Even better, placing the Eikona driver in a closed-box enclosure, with the ability to heavily dampen the rear sound waves, adding a broad notch filter to tame its measured rising high end, and matching it to a subwoofer, would more reasonably be expected to be the making of an extraordinary speaker.
 
In a proper room environment and with the right angling, the response becomes extremely linear. I also think that any adjustment to the response of this driver (and full-range drivers in general) would kill its magic.

As for the loading, my preference always leans toward TL for many reasons.

Apart from the response curves, have you ever listened to the Eikonas?
 
Unfortunately, I have not had the opportunity to listen to the Eikonas; maybe one day I will. However, if adjusting the response of a loudspeaker to make it a more linear transducer serves to kill its "magic", then maybe the nonlinear behavior is what is subjectively "magical" about its nature. Thus, it could be entirely and reasonably expected that adjusting a different loudspeaker to have a similar boosted high-end would enable its inherent "magical" qualities to also absolutely shine.
 
Unfortunately, I have not had the opportunity to listen to the Eikonas; maybe one day I will. However, if adjusting the response of a loudspeaker to make it a more linear transducer serves to kill its "magic", then maybe the nonlinear behavior is what is subjectively "magical" about its nature. Thus, it could be entirely and reasonably expected that adjusting a different loudspeaker to have a similar boosted high-end would enable its inherent "magical" qualities to also absolutely shine.
In my experience, things are a bit more complex than that.

From your comment, I gathered that you haven’t had the chance to listen to them yet. It would be interesting to discuss it again if and when you do.
 
I am new to SpicyTL and I'm trying to run the default model as a starting point. The name of the model is "01-SpicyTL-Default". It seems that the model has meaningful params entered to run without further edits. At least this is my assumption. But when I hit run I see no graph for the frequency response, just an empty grid. I am on LTSpice version 24.0.12 (x64). What am I doing wrong?
 
I am new to SpicyTL and I'm trying to run the default model as a starting point. The name of the model is "01-SpicyTL-Default". It seems that the model has meaningful params entered to run without further edits. At least this is my assumption. But when I hit run I see no graph for the frequency response, just an empty grid. I am on LTSpice version 24.0.12 (x64). What am I doing wrong?
Hi Buddy,
I’ve just updated the plot settings in SpicyTL to enable the automatic display of the frequency response and impedance curves. Please download the latest version of the software and try again. This should resolve the issue you’re experiencing.
 
@slocum What is the minimum version number of LTSpice that the simulation will run on? The latest version of LTspice doesn't want to run on my windows and I get errors when opening the default .asc schematic with an old version of LTSpice.
The important question I wanted to ask. Till this day I was using Hornresp to perform TL simulations. However Hornresp does not seem to simulate the speaker performance at the low frequency and simulates only the 1/4 effects of the transmission line. From what I see SpicyTL does not simulate this low frequency extension effect either. Is that correct?
Let me explain what I have in mind. The first graph below shows the frequency roll-off of some speaker. This roll-off depends on speaker's T-S parameters Qts, Mmd, BL. The first example shows a poorly chosen speaker as the roll-off starts already at 100Hz.
We can improve the low frequency response of the speaker mounted in TL enclosure by selecting another speaker with the above parameters more suitable for TL type of enclosure. When I modify the above T-S parameters the frequency characteristic should be extended to the lower frequency end as it is shown in the second graph. However when I alter Qts, Mmd, BL in Hornresp the frequency characteristic does not change. Can SpicyTL simulate this effect?
1736780756695.png

1736780822892.png
 
Hornresp does simulate the low-frequency performance of transmission line enclosures, including the effects of the driver's T-S parameters and the enclosure design. If the modified T-S parameters do not result in visible changes, it is likely that there is an issue with the TL configuration or the simulation settings. Hornresp and SpicyTL cannot ignore these effects unless there is a problem with your inputs.
 
@slocum What is the minimum version number of LTSpice that the simulation will run on? The latest version of LTspice doesn't want to run on my windows and I get errors when opening the default .asc schematic with an old version of LTSpice.
@polcad Which version of Windows are you running? And what are the versions of LTSpice that you have tried? It could be helpful to know those sorts of details.
 
@witwald Win7 Home. The latest LTSpice does not want to run on it.
I have installed LTSpice 4.21f and the latest SpicyTL "default" schematic opens, but during loading I get error messages "Unknown symbol syntax: V".
I do not know what it refers to. The loaded schematic is readable but with some messed up symbol in the middle. I know it is a bit ancient version but I normally use linux.
 
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@witwald Win7 Home. The latest LTSpice does not want to run on it.
I have installed LTSpice 4.21f and the latest SpicyTL "default" schematic opens, but during loading I get error messages "Unknown symbol syntax: V".
I do not know what it refers to. The loaded schematic is readable but with some messed up symbol in the middle. I know it is a bit ancient version but I normally use linux.
I can confidently say that SpicyTL worksheets maintain compatibility with LTspice XVII, but it’s plausible they won’t work with version IV, which is really quite old.

LTspice XVII should run without issues on Windows 7 (both the 32-bit and 64-bit editions).
 
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@witwald Win7 Home. The latest LTSpice does not want to run on it.
I have installed LTSpice 4.21f and the latest SpicyTL "default" schematic opens, but during loading I get error messages "Unknown symbol syntax: V".
I do not know what it refers to. The loaded schematic is readable but with some messed up symbol in the middle. I know it is a bit ancient version but I normally use linux.
These latest versions LTSpice on my Win 7 32 bit didn't want to work, but here's a version that works for me with the latest SpicyTL.
 

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