Great job Plott!……learning along the way and sharing your experiences will certainly help the community. Bravo!
Yes……you need a sub and adding one from 40hz on down with a 2nd order low pass will be transformative to say the least. All recorded bass in this region will be summed mono, so only 1 will do the trick and keeping it between the mains, low to the floor and the away from the back wall will reduce exciting the room. I would suggest a high QTC sealed box with a downfiring 12-15” driver. You’ll need DSP if you place it as I described though to add a little delay and a small boost at 35hz…..the downfiring floor boundary will take care of the rest. I suggest Dayton UM sub drivers if you can get them in your country.
My path is a little different and will be slow….I’m doing a SLOB aka Nelson Pass with some design ideas from X using 4 12” drivers per side. With this much surface area and some boost, the low end should be really exciting!
Yes……you need a sub and adding one from 40hz on down with a 2nd order low pass will be transformative to say the least. All recorded bass in this region will be summed mono, so only 1 will do the trick and keeping it between the mains, low to the floor and the away from the back wall will reduce exciting the room. I would suggest a high QTC sealed box with a downfiring 12-15” driver. You’ll need DSP if you place it as I described though to add a little delay and a small boost at 35hz…..the downfiring floor boundary will take care of the rest. I suggest Dayton UM sub drivers if you can get them in your country.
My path is a little different and will be slow….I’m doing a SLOB aka Nelson Pass with some design ideas from X using 4 12” drivers per side. With this much surface area and some boost, the low end should be really exciting!
Many thanks Richard, glad you like it.
Honestly, I can't remember how the Manzie sounds, I haven't used them recently (where recently about 1 year means...). But you've given me an idea, I'll try to do a comparison at the weekend and then report back.
I guess it depends on what you enjoy in your listening experience……When I record a 26” kick drum, it’s centered around 50hz with overtones and percussive impact down to 30. Upright bass?……40hz. Modern pop and even country have synth bass this low and kick samples are often stacked with acoustic drum response. My full spectrum masters have content down to 25hz…..i shelve them to 35 and push things higher these days as folks mostly listen to headphones or Alexa spheres…..very 😞
As low as you can go.So... do I need a sub?
Mayhem’s talking about fundamentals; I’m talking about bass at it travels and extends out to room boundaries (real or processed). ..both depend on the track/recording though.
Best result is dipole subs (stereo) in the almost near-field (within 1.5 feet of your head).
More practical is a single (mono) sub nearfield (immediately behind your back)phase-adjusted for integration with mains. non-diy ex.:
https://www.erinsaudiocorner.com/subwoofer_testing/rsl_speedwoofer_12s/
I have been out of the loop silently working on a 14 year amp project/design, I am a noob as a forum participant, not a noob to melting lead or heating glass and plates.
I have wanted something more efficient for speakers, I just can't do horns. I drove to Audio Nirvana Headquarters with the wife (a nice day trip) and while interesting, it was a travesty all the same, IMHO. I have likely offended someone, somewhere.
I am a tube only guy, period. I have a very high DF single ended triode design. That is an oxymoron right? High DF and SE triode? It is real.
A couple of years ago I ordered a pair of 2145 TB speakers. I was heading for a simple vented enclosure for my wifes 6A5g system.
I have done nothing to date (02/03/24). The speaker bug bit me a few weeks ago, winter I guess. Yesterday (02/02/24) 4x GW-1558's arrived to provide bass support to the TB's. I decided to try open baffle. This morn had some time, was poking around looking for a pass labs 6-24 XO kit for some flexible bi-amp work on the OB speaker project.... and rammed into this thread.
You have essentially done what I thought might work, not well, my first try at things outside my wheelhouse is often BAD..... speakers are not what I have any authority in. But this thread has given me some reinforcement. I meant to say, I will not DO WELL what you have attempted, not that YOU have not done well..... Just to be clear. LOL
After the poorly played back demos (my laptop), and your real FRD's, I have some inspiration to proceed.
It seems the 2145 might play well as OB. I do have concerns of the GW-1558 rising response towards 200Hz and see that you have a sizeable bump in that particular area. I also see you cut that bump with basic XO changes by 2/3rds. Again, that is inspiring. I don't expect Goldwood to have the most authentic plots, but......
Thank you for the very readable progress report for the project. It was nice to find a comparable completed project to mine with the well organized history published.
I DO want to use (4) of the 15's for woofer, rather than a pair.
I was hoping that if I had an active XO and bi-amped it might be easier to define the needed passive XO response (ideal not real) and I would be able to have a bit more low cost/time saving flexibility for manipulating real freq Response. Inductor are not cheap! Id ratehr measure twice, cut once sort of speak.
I am inspried by your project! Again thanks very much.
Mike in Memphis
I have wanted something more efficient for speakers, I just can't do horns. I drove to Audio Nirvana Headquarters with the wife (a nice day trip) and while interesting, it was a travesty all the same, IMHO. I have likely offended someone, somewhere.
I am a tube only guy, period. I have a very high DF single ended triode design. That is an oxymoron right? High DF and SE triode? It is real.
A couple of years ago I ordered a pair of 2145 TB speakers. I was heading for a simple vented enclosure for my wifes 6A5g system.
I have done nothing to date (02/03/24). The speaker bug bit me a few weeks ago, winter I guess. Yesterday (02/02/24) 4x GW-1558's arrived to provide bass support to the TB's. I decided to try open baffle. This morn had some time, was poking around looking for a pass labs 6-24 XO kit for some flexible bi-amp work on the OB speaker project.... and rammed into this thread.
You have essentially done what I thought might work, not well, my first try at things outside my wheelhouse is often BAD..... speakers are not what I have any authority in. But this thread has given me some reinforcement. I meant to say, I will not DO WELL what you have attempted, not that YOU have not done well..... Just to be clear. LOL
After the poorly played back demos (my laptop), and your real FRD's, I have some inspiration to proceed.
It seems the 2145 might play well as OB. I do have concerns of the GW-1558 rising response towards 200Hz and see that you have a sizeable bump in that particular area. I also see you cut that bump with basic XO changes by 2/3rds. Again, that is inspiring. I don't expect Goldwood to have the most authentic plots, but......
Thank you for the very readable progress report for the project. It was nice to find a comparable completed project to mine with the well organized history published.
I DO want to use (4) of the 15's for woofer, rather than a pair.
I was hoping that if I had an active XO and bi-amped it might be easier to define the needed passive XO response (ideal not real) and I would be able to have a bit more low cost/time saving flexibility for manipulating real freq Response. Inductor are not cheap! Id ratehr measure twice, cut once sort of speak.
I am inspried by your project! Again thanks very much.
Mike in Memphis
Hi Mike,
many thanks, glad you like this thread and that you have found inspiration
Take care with OB, it's really addictive...
To your project: Don't believe the factory graphs, they are only of limited use. Measure your drivers in your baffle and listening position to see how they behave in reality and then combine this with the original graphs; in fact, after taking my measurements, I simulated 2 xo's in parallel and that's how I came to my result. I wish you good luck with your project!
many thanks, glad you like this thread and that you have found inspiration
Take care with OB, it's really addictive...
To your project: Don't believe the factory graphs, they are only of limited use. Measure your drivers in your baffle and listening position to see how they behave in reality and then combine this with the original graphs; in fact, after taking my measurements, I simulated 2 xo's in parallel and that's how I came to my result. I wish you good luck with your project!
This is a great read thank you for sharing @Plott.
I'm eager to explore the OB world—after perhaps building my last speakers first—your speaker explorations would make a great contrast of opposing theories without having to fully DSP or otherwise go active and probably bi-amp.... baby steps...
I hope you decide to post up your final iteration X-over design, which final drivers, and perhaps a little dimensioned drawing of your latest baffle accomplishments?
I'm eager to explore the OB world—after perhaps building my last speakers first—your speaker explorations would make a great contrast of opposing theories without having to fully DSP or otherwise go active and probably bi-amp.... baby steps...
I hope you decide to post up your final iteration X-over design, which final drivers, and perhaps a little dimensioned drawing of your latest baffle accomplishments?