Hi,
I have a pair of transmission line speakers (full range drivers). They do some things beautifully especially really nice bass (low, impactful and sounds really correct) but unfortunately they lack "punch" on the rest of the frequencies, in a way an overly "polite" sound. Is this an inherent characteristic of transmission line speakers? thanks
I have a pair of transmission line speakers (full range drivers). They do some things beautifully especially really nice bass (low, impactful and sounds really correct) but unfortunately they lack "punch" on the rest of the frequencies, in a way an overly "polite" sound. Is this an inherent characteristic of transmission line speakers? thanks
Since it is a system, you'll need to reveal what drivers / amplifiers / source you're using. Also if you've done any comparative listening by swapping "factors" A to B (on drivers/amps/sources) that led you to ask if it's the cabinet that's responsible.
Example, "I went from flea power single ended triode to 100s of WPC solid state - and they still sound "polite" to me when played at comparable SPLs, measured by my handheld meter"
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He meant the other frequencies, not the bass...
TLs are for helping towards the lower frequencies. Since you like the bass output, I'd say you like that TL.
The rest of the frequencies, mids and highs, are from the driver(s). Maybe you are used to drivers that has spikes in certain frequencies, so you are missing what you are used to. Maybe the driver(s) do lack in certain frequencies.
Unless you measure, or at the very least share which drivers you have, we will be guesstimating what you need.
Do you have any passive filtering like baffle step or notch filters? Also, I assume you probably have some stuffing in the line, have you tried removing some of the stuffing? Those are the first two places I would look.
Greets!
Well damped ones, yes, 'think' ~critically damped (0.707 Qt) to transient perfect (0.5 Qt) and just like other speaker alignments it's about designing for the needs of the app.
'Punch' is in the ~100-180 Hz BW, so one either designs for 'punch' or bass or a BLH (a form of TL) for both.
Well damped ones, yes, 'think' ~critically damped (0.707 Qt) to transient perfect (0.5 Qt) and just like other speaker alignments it's about designing for the needs of the app.
'Punch' is in the ~100-180 Hz BW, so one either designs for 'punch' or bass or a BLH (a form of TL) for both.
Could simply be not enough HF particularly 5khz. Download free Android APP Frequency Sound Generator and you'd know in a minute. Some phones even have hearing-test-and-EQ built-in.
TLS tend to have a dip in the 100-200 Hz range and this is the punch region. It is a balancing act, look at the youtube film showing a sub TLS design using HornResp. It shows the trade of between smothness and radiation resistance.
Usually just the 3rd harmonic; it doesn't have to be a major issue & can usually be addressed via suitable driver, termini offsets & damping.
As Scott suggests, modern TL design can almost completely deal with the ripple caused by the undesired harmonics making it out the terminus. The biggest and hardest is the third harmonic, where it falls depends on the line tuning. MJK showed that a driver offset can deal with this harmonic very well.
dave
dave
Thanks a lot for all the answers, really interesting points and a lot to think about. The speakers are mini towers using 2 identical 4 inch drivers one running full range and the other one starts rolling-off at 1khz. The transmission line fires at the bottom. I did a lot of A/B and a lot of work on positioning and I will tell you my conclusions. First-off to clarify that what I mean by "punch" (maybe it's not the right word) is not low-end kick which is actually pretty good for the size of the drivers & speakers (+ I'm using a subwoofer) and also definitely not top-end attack (which is also very good) but rather the sense in certain midrange frequencies of "politeness" (the instruments being very gently played if you like, a certain kind of roundness of the sound, a frequency-dependent laid-back sound). Soundstage, imaging, separation is brilliant. I'm using tube amplification (a Leben CS300XS) and sound is consistent with any type of source, although more evident with analog (digital I guess is sharper by design). What I found helps is:
My theory is that I'm facing some kind of frequency imbalance (as also stated by one of the friends above), sometimes it can be frustrated but I do also like their sound. I came across a post in this forum that described transmission line speakers as "lacking punch" so I was wondering if this was something more or less consistent with the design.
- Running the speakers on the 4ohm vs the 8ohm post which seems to increase the issue.
- Positioning closer to the walls (which sadly reduces soundstage).
- Speaker wire (I've used QED silver and things improved).
- Choice of tubes also plays a role.
My theory is that I'm facing some kind of frequency imbalance (as also stated by one of the friends above), sometimes it can be frustrated but I do also like their sound. I came across a post in this forum that described transmission line speakers as "lacking punch" so I was wondering if this was something more or less consistent with the design.
That is a great point and that's exactly how I feel. Unfortunately at this stage I am not able to take the speakers apart so I have no way of knowing what drivers were used, but agree with your assesment, it makes absolute sense.
It could, another friend above mentioned it but I don't have the experience to change it.