[matevana]

Previously I had the opportunity to play with a few hemp cone drivers in open back.  The material has been used primarily in guitar and bass speakers in an effort to produce a certain tonal signature (voicing).  These speakers are typically highly efficient but their response curves can be a bit ragged for home hi-fi.

There are however a few hemp based drivers that seem to be the exception to the rule. One such driver, the ‘Lil Buddy, is manufactured by Eminence Speakers in Kentucky and is part of their 10” Patriot line. It has a sensitivity of 99.1dB (1w/1m) and a Qts of .84. The response curve is also remarkably flat. I would like to put in the good word for this driver as a midrange in an OB configuration. Coupled with an appropriate bass driver and tweeter, it can be the cornerstone of a really impressive system.

I have spent the past few weeks listening to this driver handle the midrange duties in the Hestia Forte speaker.  In this particular application it is technically used as a lower midrange unit, but I have also listened to it as a wide range driver coupled only to a tweeter and have been equally impressed.

While it has a powerful physical sound, it is also very smooth. The hemp/paper/pulp cone with paper former rolls-off differently than any other driver I have heard. The break-up, even above 5k, is extremely smooth and almost audibly nonexistent.  This adds a sweet character that really seems to lend itself well to the open back experience.

For a guitar speaker it has a very neutral voicing, if anything a bit on the dark side. This character tends to naturally subdue the highest octaves and make crossover work easy. It functions well with a single inductor HP filter, with no real need for additional impedance equalization. And unlike many drivers, perhaps due to its voicing, it sounds fine with a simple 6dB per octave filter. If coupled with a smooth tweeter and crossed relatively high, it might be possible to design a network with only two components.  I have used the driver in the 150 Hz to 5k Hz bandpass with impressive results. 

This is one of those situations where it is helpful to hear the driver on an open baffle to properly evaluate.  I would be interested to know if anyone has had a similar experience with hemp cone drivers.

[steve f]

Matevana,

 I agree with you completely. I  listened to a 2way with a Tone Tubby 12" and a Lowther that was quite good. The hemp cones do appear toroll off smoothly without a harsh breakup. I think you're really onto something good.

Steve

[matevana]

Interesting. I just borrowed a 12" Tone Tubby with Alnico magnet from a friend. Looking forward to hearing that as well.

[steve f]

The design I listened to was a Lowther America design. It was the smaller open baffle speaker. 
Steve

[matevana]

I spent the weekend listening to the 12" hemp cone Tone Tubby driver w/AlNiCo magnet.  Very nice driver. I just cant justify the difference in cost between that and the 10" Eminence Lil Buddy ($79) or even the larger Eminence Cannabis Rex ($99).  I plan to stick with the Lil Buddy in the Hestia Forte for now. The more I listen to it, the more I like it!   

[BoJonJovi]

In the last week or so i put a post up asking for opinions on creating some speakers specifically for blues and guitar using guitar speakers. I also had a jones for hemp. You can imagine the responses most of which I agreed with.
After reading all the posts I got I reluctantly gave up on the idea.   You have reaffirmed that perhaps i was on the right track. Thanks so much for this post as I have had this idea rattling around and pestering my brain for a couple years.

[BoJonJovi]

Nice Job!

[matevana]

Thanks!  After living with hemp cones for several weeks now I really like them. I'm surprised that no one seems to make a hemp midrange driver in the 3-5" range. So many of the true midrange drivers seem like they would benefit from a more natural roll-off, particularly when they are used toward the edges of their range or with lower order crossovers. If the concern is that one might lose detail with a heavy paper cone, I have not found this to be the case with the Eminence products.

[golana]

If the concern is that one might lose detail with a heavy paper cone, I have not found this to be the case with the Eminence products.

Don't know about Eminence prods. But, TT's claim was by using hemp, it made the paper many times stronger. And the made the cone thinner, and thinner, and thinner.,

[-Richard-]

Hi Matevana ~ A very exciting and interesting thread. I deeply appreciate your taking the time to share your experiences with us of the Lil' Buddy hemp cone drivers from Eminence.

I have come to regard 'smooth' as easily one of the most important sonic characteristics a speaker can have. It creates a more 'relaxed' sonic personality that fits the kind of music that Deborah and I mostly listen to.

I am very interested to try a pair in a simple OB. I have come to feel that observations about drivers from our wonderful OB community would be even better served if we can have a sense of ancillary equipment being used with them. Especially the amplifier/preamplifier. With that in mind can you share with us what amplifier/s you are currently using with your Lil' Buddy's?

Also, what tweeter have you used?

Again, I am very excited that there is a reasonably priced hemp wide-range driver that you really like, thanks for sharing!!

Incidentally, did you prefer it in OB or in a box/cabinet?

With Warmest Regards ~ Richard

[matevana]

The chain looks something like this:

Music server -> Micromega Mydac -> Luminous audio passive preamp -> B&K ST-140 Power Amp (upper cabs) -> Adcom GFA-5500 Power Amp (lower cabs)

I have used the Vifa XT19 and D19 tweeters with this design. I also like the Usher 9950 and would someday like to test the AMT style tweeters (air motion). 

Sorry, I have only listened to this driver in OB.

[-Richard-]

Here is a description of the 10" Eminence Lil' Buddy Hemp driver copied from 'reviews' from people who have purchased it on Parts Express.
-----
It is what it is but it's really good.
OK this is the deal with this speaker. It's part of an excellent line of 10 inch speakers made by Eminence. Each one is voiced differently. I do have most of them in one amp or another because I build small amps. Just SE 5-10 watt Champ type amps.

I bought this speaker specifically for one amp I built, it's for slide guitar. This speaker did exactly what I expected. The highs were slightly attenuated which was what I wanted and the mids were thick and kind of barked at you, which was also what I wanted. For lack of a better description it's almost like a 12" speaker, similar to a more British sound (Celesetion)than American.

The Brit sound is more of that midrange bark as opposed to the more American (Jensen)smooth highs and scooped mids. I'm guessing but usually you get that with a heavier paper material for the cone, hence the hemp cone's effect and the larger 1.75 inch voice coil. I guess Eminence was after the Tone Tubby sound, whether they achieved that or not, I don't know I never used a Tone Tubby.

This will thicken up a bright midrange deficient amp and would probably work well in a multi mixed speaker cabinet maybe with a Red Fang. Like all speakers it has a voice, if not used in the right amp I can see people not appreciating the Lil' Buddy. It is what it is, it will add midrange and attenuate highs in whatever amp you put it in.
---------
A bold sounding speaker, you think it is a 12", with late breakup and smooth top end, I stuffed mine in a 66' Princeton Reverb, I can not think of a more interesting combination of amp and speaker. Two days delivery for FREE, how can you beat that
---------
Warm, dark speaker lacking high end. Maybe useful in tandem with other brighter speakers or to tame a shrill amp, but definitely not the ticket for a 1x10 combo, unless you're a harp player (would be great for that). Also, don't think you're saving money and getting the same speaker as Tubby ceramic 10. The 'Buddy' has a smaller magnet and a much larger dome which rolls off highs. The TT is much more full-range/bright.
---------

I have copied these comments to suggest that any perception of a drivers performance is equipment dependent. It is not an isolated sonic 'event' that can be simply integrated into ones existing equipment as a 'neutral' addition. This is something I have become particularly sensitive to over the last few years.

It could be that if one favors using a tube amplifier, a single ended triode flavor for example, that the apparent fat or rich sound of this drivers mid-range may not be entirely compatible with certain music (with other music it may be spectacularly effective).

This raises the question, why would anyone want to 'start' with a SET tube amplifier in the first place? Or with any particular amplifier? Wouldn't it be best to begin with a driver (especially in the OB paradigm) and then choose an amplifier that is especially compatible with it?

This business of where to 'start' with ones equipment in one of the most confusing aspects of audio, especially for someone just beginning to enter into this highly rewarding 'hobby' (if you are a music lover of course and not just a techno-geek looking for his next fix). For most of us it may come down to what equipment we have on hand and we go from there. There is something random in that of course, but also it makes the question of where to start easier.

I have come to like or even crave what a writer recently referred to as the 'hall sound' of SET amps. Which is to say, the sound of the 'space' in which the music was recorded (if indeed there was a 'space' and it was not recorded in the controlled/engineered 'space' of a recording studio). Also I like the way SET's extrude the 'sound' of instruments and voices to render them more dimensional. Perhaps an artificial re-creation of 'live' but one that is very satisfying for Deborah and I.

So if I begin with using an SET amp for the reasons I have suggested, then what driver we use will have to have a sonic synergy with that.

The B&K ST-140, was a highly regarded SS amp when it was available. It could be that the SS circuit 'sound' is helped (its 'voicing' has a nice synergy) with the Lil' Buddy's rich mid-range.

Only experimentation will know for certain if the Lil' Buddy will work its magic with ones amplifier and ancillary equipment. But the fact that it is reasonably priced certainly makes the journey an exciting adventure to have fun with.

Also, I have one other 'observation' I would like to share. That is, that whenever I have heard a well-executed electrostatic, or planar-magnetic, or ribbon driver (essentially, non-cone/pistonic drivers) they always sound quite incredible on material in the upper mid-range and higher frequencies, but seem less convincing in the lower-to-mid-range area, where so much of music lives, especially the voice. Here is where a driver like the Lil' Buddy's hemp cone material may be especially effective.

Again, thanks, matevana, for sharing your insights with us. I am still very intrigued with experimenting with 10" hemp sound. It could be the perfect low price OB driver solution for music that 'lives' in the magical midrange.

With Warmest Regards ~ Richard

[-Richard-]

Frequency curve from Parts Express for the Lil' Buddy 10" hemp mid-range speaker.

With Warmest Regards ~ Richard

[golana]

Wondering if anyone has played around with this eight incher. What about mating it with AE LO15's. Maybe down near 200-300.
http://www.tonetubby.com/specs/low-watt-alnico-8-8.html

[matevana]

Yes.  It's warm and sounds good at low volume but the break-up mode comes way too early. Sounds great with my '57 Strat reissue but I would rule it out for home audio. This thing is designed to be overdriven easily with low power guitar practice amps... and not what you would want for hi-fi.

The 'Lil Buddy by comparison is designed to break-up later so it remains clean at louder levels. Some of the Weber Alnicos are also nice and can be ordered with a hemp cone option.
 

[Pchelac]

http://www.tonetubby.com/low-watt.html   Interesting drivers too

http://www.tonetubby.com/specs/low-watt-cramic-8-8.html   Good extended midrange for OB, I think...