[Rocket]

Hi Dennis,

Any progress with the new speaker design?

Regards

Rod

[DMurphy]

Well, I've had a prototype up and running in my living room for a couple of weeks.  If you love raw mdf, you will love my speaker.  I'm happy with the tweeter and mid, and I'm actually happy with the woofer in its current box.  But Jim thinks we can do better in the bass department, and that's the issue.  I know he's trying out a difference box, but hasn't come to any conclusions yet. So I will wait for that to be resolved, and then I'll revise my prototype to accomodate the new bass response characteristics.  And then--and then--Jim will have to decide whether it's silk or sow, and if silk, how to make it look like something someone will want in his (well--her) living room.

[nyc_paramedic]

Well, I've had a prototype up and running in my living room for a couple of weeks.  If you love raw mdf, you will love my speaker.  I'm happy with the tweeter and mid, and I'm actually happy with the woofer in its current box.  But Jim thinks we can do better in the bass department, and that's the issue.  I know he's trying out a difference box, but hasn't come to any conclusions yet. So I will wait for that to be resolved, and then I'll revise my prototype to accomodate the new bass response characteristics.  And then--and then--Jim will have to decide whether it's silk or sow, and if silk, how to make it look like something someone will want in his (well--her) living room.

I apologize in advance if this a really stupid question.

I have been reading of some very hi end speaker models being constructed of very high quality plywood; B&W's Signature Diamond, Sonic's Allegretto, and NuForce's SP9(?) come to mind.

Has Salk experimented and/or considered using high quality (Birch?) plywood for a speaker design?

[funkmonkey]

Jim and I have discussed the possibility of using bamboo ply for a cabinet...  I think that if he could find a competitively priced local supplier for the bamboo he would explore that option further.  The Birch ply should be much easier to find, but I'm not sure that it is significantly less resonant than MDF.  Carbon fiber is another cabinet material that I find intriguing...

[jsalk]

There are those who say Baltic Birch plywood is the best material for speaker cabinets.  We have used it when requested by a customer.  It is quite a bit more expensive and not quite as easy to work with as it does not machine as well.  We have A/B'd it with speakers built with MDF and can't really say it made an audible difference.  I won't say fans of Baltic Birch are wrong about this, in our tests we just haven't been able to determine that they are correct.

As funkmonkey pointed out, we are also exploring bamboo.  Right now, it is very expensive at about 10 times the cost of MDF.  But we built a pair of bamboo SongTowers last week and will be finishing that pair shortly (I'll post pics when they are done).  It is certainly a sustainable, eco-friendly alternative.  It is also nice to work with (machines well) and it can be finished naturally without veneering (something we find very attractive).  Lower finishing costs may off-set the higher initial costs, so we find it intriguing.

We have also started working with 1" MDF, sandwiched 1 1/2" MDF and even sandwiched 2" MDF.  These show a great deal of promise, especially at low frequencies where added mass can really be a benefit.

But in the end the most important thing, no matter what material is being used, is that it be well-braced.  All of these materials benefit immensely when braced properly.

As for carbon fiber, my interest level is very low.  I talked to one manufacturer who was crying the blues because the materials were in such short supply he could not deliver product.  It is also very expensive and not the kind of thing you want to work with if you are concerned about your health.

There are also other materials we would like to explore.  One is high-density foam.  You can formulate these materials in virtually any density you would like - far denser than any of the above materials.  And you can use forms to mold it into any shape you want.  Of course, that would pretty much preclude a wood finish.  Automotive finishes anyone?

- Jim

[Marbles]

I can't wait to hear more about the HT4; drivers, configuration, active or passive woofer, cabinet shape, frequency response etc...

[bigbwb]

Jim,

the bamboo ST's you mentioned intrigue me.  Can you provide any more details(are they just bamboo veneer or solid bamboo)?  I ask because as a ascend sierras owner, the bamboo cabinets used on them are some of the most solid non-resonant cabinets I have ever seen.   I truly beleive this wood would enhance any speaker design and limit any unwanted cabinet resonances but is costly though.

Brandon

[jsalk]

Jim,

the bamboo ST's you mentioned intrigue me.  Can you provide any more details(are they just bamboo veneer or solid bamboo)?  I ask because as a ascend sierras owner, the bamboo cabinets used on them are some of the most solid non-resonant cabinets I have ever seen.   I truly beleive this wood would enhance any speaker design and limit any unwanted cabinet resonances but is costly though.

Brandon

The bamboo we are using is a solid 3/4" sheet of bamboo plywood made with laid-up strips of bamboo.  It is fairly attractive a machines very well. 

As for Ascend's product, I am not sure, but I was under the impression that it was a "trans-laminate" design.  In other words, a CNC router is used to cut each "slice" from the front of the cabinet to the rear and then all these layers are laid up and glued together.  This way, the walls can be any thickness desired and even variable.  Bracing can be cut into every Nth layer as well. 

I think this lamination process has more to do with the performance of the cabinet than the bamboo.  This technique is used with other materials such as MDF. 

- Jim

[bigbwb]

Jim,

the bamboo ST's you mentioned intrigue me.  Can you provide any more details(are they just bamboo veneer or solid bamboo)?  I ask because as a ascend sierras owner, the bamboo cabinets used on them are some of the most solid non-resonant cabinets I have ever seen.   I truly beleive this wood would enhance any speaker design and limit any unwanted cabinet resonances but is costly though.

Brandon

The bamboo we are using is a solid 3/4" sheet of bamboo plywood made with laid-up strips of bamboo.  It is fairly attractive a machines very well. 

As for Ascend's product, I am not sure, but I was under the impression that it was a "trans-laminate" design.  In other words, a CNC router is used to cut each "slice" from the front of the cabinet to the rear and then all these layers are laid up and glued together.  This way, the walls can be any thickness desired and even variable.  Bracing can be cut into every Nth layer as well. 

I think this lamination process has more to do with the performance of the cabinet than the bamboo.  This technique is used with other materials such as MDF. 

- Jim

Jim,

You have a PM.

[jsalk]

Marbles -

I can't wait to hear more about the HT4; drivers, configuration, active or passive woofer, cabinet shape, frequency response etc...

Our goal is to introduce this model (I don't know what it will be called) at AKFest in early May.  Of course, that is dependent on having everything come together on time.  This is a very ambitious project.

I don't want to say anything about it now, but I can tell you that the woofer section design is complete and passed with flying colors.  The F3 will be about 18Hz with in-room response to 15Hz.  One of our goals was a speaker that was flat from 20Hz to 20KHz, minimum, and that goal has been met.  Absolutely no sub will be needed with these speakers!

- Jim

[zybar]

Marbles -

I can't wait to hear more about the HT4; drivers, configuration, active or passive woofer, cabinet shape, frequency response etc...

Our goal is to introduce this model (I don't know what it will be called) at AKFest in early May.  Of course, that is dependent on having everything come together on time.  This is a very ambitious project.

I don't want to say anything about it now, but I can tell you that the woofer section design is complete and passed with flying colors.  The F3 will be about 18Hz with in-room response to 15Hz.  One of our goals was a speaker that was flat from 20Hz to 20KHz, minimum, and that goal has been met.  Absolutely no sub will be needed with these speakers!

- Jim

 

[Nuance]

Wow - these are certainly going to be something special.  I should be able to afford them in 30 years or so.   

[bigbwb]

Jim,

You have another PM

[/quote]

The bamboo we are using is a solid 3/4" sheet of bamboo plywood made with laid-up strips of bamboo.  It is fairly attractive a machines very well. 

As for Ascend's product, I am not sure, but I was under the impression that it was a "trans-laminate" design.  In other words, a CNC router is used to cut each "slice" from the front of the cabinet to the rear and then all these layers are laid up and glued together.  This way, the walls can be any thickness desired and even variable.  Bracing can be cut into every Nth layer as well. 

I think this lamination process has more to do with the performance of the cabinet than the bamboo.  This technique is used with other materials such as MDF. 

- Jim
[/quote]

[funkmonkey]

But we built a pair of bamboo SongTowers last week and will be finishing that pair shortly (I'll post pics when they are done).  It is certainly a sustainable, eco-friendly alternative.  It is also nice to work with (machines well) and it can be finished naturally without veneering (something we find very attractive).

That's very cool Jim!  I really like working with the bamboo ply too, but because of the cost don't get much opportunity to.  It is really solid stuff...   for grass    I am anxious to see some pics of the bamboo-ST when they are done.  Did you get the dark or light bamboo-ply?  Are you going play with dyes on the first pair, or just clear coat the natural color?

The HT4s sound like they are going to be awesome.  I'm really curious about their size now, 15Hz in-room impressive and most likely a pretty good size driver and a very good sized box. 

[jsalk]

But we built a pair of bamboo SongTowers last week and will be finishing that pair shortly (I'll post pics when they are done).  It is certainly a sustainable, eco-friendly alternative.  It is also nice to work with (machines well) and it can be finished naturally without veneering (something we find very attractive).

That's very cool Jim!  I really like working with the bamboo ply too, but because of the cost don't get much opportunity to.  It is really solid stuff...   for grass    I am anxious to see some pics of the bamboo-ST when they are done.  Did you get the dark or light bamboo-ply?  Are you going play with dyes on the first pair, or just clear coat the natural color?

I got light (natural) bamboo.  There are some small scraps left over and I plan to finish them at the same time.  I will probably finish these natural, but will do samples of the scrap with different dyes to show what can be done.

The HT4s sound like they are going to be awesome.  I'm really curious about their size now, 15Hz in-room impressive and most likely a pretty good size driver and a very good sized box. 

Yes, small rooms need not apply...

- Jim

[gthomas]

Jim by not needing a sub with the HT4 I assume you mean for two channel listening.  What about HT use?

[JerryM]

Jim by not needing a sub with the HT4 I assume you mean for two channel listening.  What about HT use?

15 Hz in room response??! I'm just guessing here, but HT use is covered. 

Have fun,
Jerry

[jsalk]

Jim by not needing a sub with the HT4 I assume you mean for two channel listening.  What about HT use?

Well, if you think of it this way, with a pair for the left and right mains, you have two subs that play to an F3 of 18Hz.  Do you need more?  On the other hand, I would have to investigate whether or not all the LF info is routed to the mains if the system was set up with no sub (I've never tried this).  Perhaps someone with some experience could address that question.

- Jim

[gthomas]

Well, as long as there are seperate wiring posts for the woofers, then you would amp them seperately and then run the subs out from your pre-pro just as a stand alone sub.  Are you planning a new center also?  I could see selling my HT1 surrounds and replace them with my current Ht3s.  Also could sell my Jl Audio F113 subs.  My wife will be killing me!!!

[rydenfan]

There are those who say Baltic Birch plywood is the best material for speaker cabinets.  We have used it when requested by a customer.  It is quite a bit more expensive and not quite as easy to work with as it does not machine as well.  We have A/B'd it with speakers built with MDF and can't really say it made an audible difference.  I won't say fans of Baltic Birch are wrong about this, in our tests we just haven't been able to determine that they are correct.

As funkmonkey pointed out, we are also exploring bamboo.  Right now, it is very expensive at about 10 times the cost of MDF.  But we built a pair of bamboo SongTowers last week and will be finishing that pair shortly (I'll post pics when they are done).  It is certainly a sustainable, eco-friendly alternative.  It is also nice to work with (machines well) and it can be finished naturally without veneering (something we find very attractive).  Lower finishing costs may off-set the higher initial costs, so we find it intriguing.

We have also started working with 1" MDF, sandwiched 1 1/2" MDF and even sandwiched 2" MDF.  These show a great deal of promise, especially at low frequencies where added mass can really be a benefit.

But in the end the most important thing, no matter what material is being used, is that it be well-braced.  All of these materials benefit immensely when braced properly.

As for carbon fiber, my interest level is very low.  I talked to one manufacturer who was crying the blues because the materials were in such short supply he could not deliver product.  It is also very expensive and not the kind of thing you want to work with if you are concerned about your health.

There are also other materials we would like to explore.  One is high-density foam.  You can formulate these materials in virtually any density you would like - far denser than any of the above materials.  And you can use forms to mold it into any shape you want.  Of course, that would pretty much preclude a wood finish.  Automotive finishes anyone?

- Jim

Jim, I have quite a bit of experience working with both Carbon Fiber and high-density foams. Feel free to shoot me a PM if you ever want to discuss them. You can see our finished product here: http://www.donzimarine.com/

Make sure to look when you have a few minutes and explore some of the bigger models