New Lowther Drivers.


I have ordered a pair of the new, improved Lowther DX3. The improvements consist of changing the suspension from a rolled-out type to a rolled-in type, putting a rolled edge on the whizzer cone to stiffen the edge and eliminate the midrange peak called "Lowther shout". They also offer a new phase plug that looks like a "light bulb with holes" that is controversial. Bullet style phase plug is still standard. They are sending me both types for evaluation.
I am currently building a set of Voigt Pipes enclosures, which I hope to get done before the drivers arrive. I am following the plans from the Lowther Club of Norway website.
I'm very excited about this, because I could use some extra efficiency in my speakers. If anyone has built these Lowther Voigt Pipes before and can offer some advice, it would be appreciated. It is not really hard, but sometimes a simple tip can make the difference. BTW, Doug(Grandpad), you really helped me to make up my mind on buying these drivers in the last thread I put up on this topic. As always, I will give reports on results, just in case anyone is interested. Comments?
twl
No, no, NO, twl! You've missed my point completely. And you've gotten defensive, which was NOT what I wanted.

You and I have been through this before. If the composer didn't want you to hear pitches below 40Hz then s/he would not have written them. So by definition, dear friend, when you truncate the audio spectrum you are choosing to listen to something other than what the composer intended you to hear.

This has nothing to do with how technically or musically literate you may be, as I think you very well know.

It is borne in upon me yet again that nearly any sort of attempt at this kind of discussion will be overwhelmed by ideological pronouncements cast set forth in the language of martyrdom or righteous wrath. Very wearying.

will
Good Bishop:

You wrote: "This again brings us to the perennial question of whether we are listening to the sound or to the music. It is pretty clear when twl makes statements like "I can live with 40Hz" that he is opting for listening to the sound."

Not only is it NOT "pretty clear" but I think you introduce a complete, and quite unkind, non sequitur. If one looks at any materials on designing or building audio equipment the discussions are all the same. They do not, for the most part, or at least at the beginning of the design stage, stay in the language of music, but rather in the language of electronics and acoustics. It can't be helped. Don't blame Twl for it.

You will not get to first base without asking the simple question: what do I want the equipment to do? A most basic aspect of this process is determining frequency response for the piece you are building (amp, speaker, whatever). The folks who developed your lovely Utopia's undoubtedly talked in this manner. Does it mean that they have choosen not to listen to music and are only interested in sound? That is ludicrous. It simply means that they have turned off the record player for a while and stopped listening to music in order to work on audio equipment. It's not that they have choosen not to ever listen to music. It's just at the moment they are doing a different thing...designing audio equipment. It is somewhat akin to saying someone who practices scales is interested only in technique and tone and not music when, in fact, one follows directly from the other.

Take another example. Some time ago you were involved in helping a friend build a listening room. This entails looking at and talking about rooms in terms of sound and acoustics. In describing the first steps in this direction one might say something like this: Well I established the basic axial resonant frequencies of the room by dividing the speed of sound by the 2xlength of the room. (1130/2L). Finding the basic resonant frequency to be 44Hz, I put on a frequency disk on the stereo and fired her up at 44Hz and walked around the room trying to identify high pressure points in the room. I then built a few bass traps tuned to that frequency and started experimenting with placement of them based on the SPL measurements. (Your first steps in tuning a room may differ and be much better(not the point.)) The point is that tuning the room inevitably requires an approach, and discussion, along these lines and it resembles Twl's talk about speakers. It can't be avoided! It would be pure folly for someone to say "See, the Bishop is only concerned about sound and the frequency response of his room and has choosen not to listen to music."

Of course, when such measurements and things are done you will sit back, turn on the music, and your ears will be the ultimate judge. But your ears alone will never tell you HOW to build a good sounding circuit or what to do in order to make your listening room sound musical. They will tell you when and if you do it. But never HOW to do it.

I've read some of your posts and you are not stupid. The point above is so obvious, that I find it hard to believe you do not see it. It almost makes me agree with Twl that you are setting out to insult him (as sugar coated as the insults are).

In any event, I'd like to see Twl keep posting so I can learn from his Lowther project and would appreciate it if you would respect his request. He might otherwise stop posting or something and I'll lose some valuable insight into FR drivers.

I remain,
Dekay, it's good to hear that you and others are considering the benefits of single driver systems. I'm sure you know that you needn't "get on my good side" :-) in order for me to try to give you any assistance I can. My main reason for doing this type of post is to help others see that there are some different ways of doing things in audio than the usual run-of-the-mill. And to help them benefit from my experiences, good or bad. Apparently, there are some who would ridicule me for my views. But, they are far in the minority and I prefer to concentrate on my projects and helping any members that may be interested. If I can be of any help to any of you, please email me, and I will give close attention to your needs, and give whatever help I can. I do not claim to be the ultimate authority on these subjects, but I am working with these concepts and products, so I do have some good working knowledge of them. As for the 40Hz cutoff for the Voigt Pipes, I may not even quite get down to 40Hz, but I will try to get what I can without sacrificing any midrange quality. I would love to get to 20Hz, but it's not possible with this design. My efforts are to get the most from the least and typically that will entail some trade-offs, in this case, the deepest bass is REDUCED but not eliminated. While some may consider this "sacrilege", I feel that all designs are limited and one has to pick their weak points as in all engineering and design work. My preference is to accept lower output in the 20Hz-40Hz region, in order to get the advantages offerred in the rest of the spectrum by single driver designs. There are more exotic cabinets available that will give 32Hz cutoff for the same drivers. Maybe, down the road, I will build them. I feel honored that Albert, in particular, is interested in my efforts in this area, because of my great respect for his knowledge, experience, and integrity. At the end of this road, we will know more than when we started, and that, in itself, is worthy of the effort.
Bishopwil, I remember our previous discussions, and I am not in conflict with your statements regarding the proper reproduction of very low bass frequencies and their effects on the composer's intended sound. As I posted above, I am simply making a conscious decision to accept this weakness in order to get benefits in other areas. We may not agree on the "sacrifice" of flat response in this octave of the spectrum, but I think we will agree that no product is perfect, and we all "sacrifice" something with every audio product we buy, so we can get the things that we do want out of them. Upon looking back to my statements on other threads, this may apply to the other diagreements we may have had on the other topics. Perhaps I should have been less forceful with my statements. While I may have been rather "absolutist" on the vinyl topic, I am not nearly as "absolutist" on this topic. However, I have selected a path, and I am traveling it. Things will be learned on the way. Others may benefit from my experience. Ultimately, my conclusion may, or may not, support my premise. We shall see. If I misinterpreted your intentions in your post, I am truly sorry, and have no desire for conflict. I do have certain sensitivities, as does anyone, and can react defensively.
Clueless, don't be concerned about me not posting my results. I will make sure that anyone who wants the information, will have it. Thanks for your support of my thought processes regarding equipment design, and your eloquent descriptions.

I remain,