Jack 110 questions

[shclark]

Finally retired and getting ready to start my build. I've read different opinions on using a tweeter in this cab for bass. Very much like having the tweeter in my Fender combo amp, but it's heavier than I'd like...GK microbass is a great size, but misses the solid low and high ends that the Fender supplies.....so hoping the Jack 10 lite will fix all that. Playing 5 string with roundwounds for jazz, r&b, blues....and all at moderate volume. May go fretless and possibly electric upright and again, assume this would be a fine cab for all that too. Would it be a big pain to start out without the tweeters and add later if I miss them? Better to just put in right off? Also, if I understand Bill's note about updates right, the current plans are the same as the ones I purchased in 2016. Just checking. Thanks in advance for any help. Steve

[Bill Fitzmaurice]

IMO tweeters are a must. Even to the extent that woofers reproduce above 2kHz it's with very narrow dispersion. If you play flatwounds while wearing mittens with the treble EQ off above 2Khz won't matter to you, but otherwise...

[9830Lark]

I left the tweeters off on my J10 Lite. I play P-bass with flats. I'm very happy with it, but in hindsight, I'd put the tweeters in and just EQ as needed.

[Bill Fitzmaurice]

Better to have them and not need them than the other way around.

[shclark]

Thanks for the notes! Yup, that's kind of what I thought. That takes care of the high side. One more puzzle for me is whether I'll hear much difference using S2010 instead of Beta 10. I'm expecting a great low end sound either way, but is one speaker better than the other?

[Bill Fitzmaurice]

From the plans, page one: low frequency output capacity is determined by the driver excursion limit, xmax...The Beta 10 has 3mm xmax, the S2010 4mm, the 2510 4.8mm.

[Seth]

3mm to 4mm Xmax is a potential difference of 2.5dB
3mm to 4.8mm Xmax is a potential difference of 4dB

[shclark]

I'm leaning toward the S2010.
So in terms I can understand, the higher xmax is useful for a cleaner low response at higher overall volume? Would I notice much difference at low volume?

[Seth]

I'm leaning toward the S2010.
So in terms I can understand, the higher xmax is useful for a cleaner low response at higher overall volume? Would I notice much difference at low volume?

It's not likely that there would be enough of a difference in response between drivers to notice. You'll be good with the S2010

[shclark]

The baltic birch came today and it's finally time to make sawdust - more questions

with the pl adhesive, it looks like best to use it anywhere possible, but I'm not sure about the edges of the smaller braces, especially the ones that are hot glued into position

I'm planning on 4 tweeters in a flat array in series parallel, so with regard to the crossover, am I getting it right to figure a 2k high pass and a 2k low pass in parallel?

also, for bass guitar, would there be any point in using more than 4 tweeters?

Thanks again for great plans and all the ideas!

[shclark]

For electric bass, I'm figuring on 4 tweeters in series parallel.
Is it about right to put in a low pass filter at 2k and a high pass filter also at 2k?

[Tom Smit]

Yes, that's right.

[shclark]

So now I am officially building my Jack 110 lite. The instructions are really excellent! Having read them over 20 or 30 times, they're even sinking in) The folded horn design is really good looking and I even hesitate to put the horns in front because it is just so nice to look at. Almost seems a shame to cover the Baltic birch with duratex, but probably makes more sense, especially being my first cab. Anyway, my original plan was to use the melded tweeter array, but then noticed it would be easier to build in the flat format. So I started to build with that in mind. Then I saw how beautiful the curves look and the flat array looks, well, flat.......more I think about it though, my most frequent use for the cab will probably be on the floor in small rooms, less than 30 feet, where the wider dispersion could be a real factor. Does that make sense for my purpose? Probably should be a little pragmatic sometimes. Still, I think the melded array would suit the aesthetic a little closer - to my eyes anyway. I'm hoping to add some short legs to tilt the cab up from the floor a bit. thinking of putting threaded inserts on the sides and using thumbscrews to hold them in place while in use. Maybe someone has already done this and found a better way? Thanks again for all the answers and the excellent plans. Beautiful design!

[AntonZ]

I have put melded arrays in the mouth of an Omni 10.5, a long ago predecessor to the Jacks. It does indeed look nice in the mouth and the wider dispersion is exactly why I put it there. It works well.

For the tilt thing you might want to consider installing a fold out handle in the bottom of the cab. Not for lifting but for tilting. The legs with thumbscrews may work but it sounds a bit tedious to me. Set up and tear down is never going fast enough to my liking.

[shclark]

Thanks for the note. Yes, the thumbscrews are a bit of a time taker. Thought about fold out legs like the old Fender Bassman amps used, but seems like they'd scrape off the duratex quickly. Hmmm,

Regarding the melded array, I'm thinking about using 6 tweeters - it's just for bass - no PA. Is that overkill?