Hello,
I have a pair of 802D and 416A in good condition and I'm looking for the best cabinet/horn designs for mounting them.
Thanks in advance,
Bob
I have a pair of 802D and 416A in good condition and I'm looking for the best cabinet/horn designs for mounting them.
Thanks in advance,
Bob
'Best' is a 'floating target' based on ALL the needs of the intended app; otherwise, my default recommendation is to use the pioneer's reflex alignment = (measured) Vas/1.44 = cab net volume (Vb) tuned to (measured) Fs = box tuning (Fb).
The basic requirement for a horn is its XO point/slope order and polar response with this driver combo being either 500 or 800 Hz/2nd order, ~ 90 H x 40 V.
The basic requirement for a horn is its XO point/slope order and polar response with this driver combo being either 500 or 800 Hz/2nd order, ~ 90 H x 40 V.
Model 19 is what most people like the most with that drivers combination. Off course it's a very oldskool and old design.
The plans are here:https://greatplainsaudio.com/gpa-vintage-altec-ezine/altec-lansing-model-19-cabinet-plans/
And for that you also need the Altec H-811B horn and the N1201-8 crossover (plans of that are here: http://www.audioheritage.org/vbulle...c-Lansing-Model-19-crossover-issues&styleid=9)
But if that also fits your plan, i can't tell, it's just what most do. Some do custom cabinets and put the woofer in an Onken style cabinet and so...
The plans are here:https://greatplainsaudio.com/gpa-vintage-altec-ezine/altec-lansing-model-19-cabinet-plans/
And for that you also need the Altec H-811B horn and the N1201-8 crossover (plans of that are here: http://www.audioheritage.org/vbulle...c-Lansing-Model-19-crossover-issues&styleid=9)
But if that also fits your plan, i can't tell, it's just what most do. Some do custom cabinets and put the woofer in an Onken style cabinet and so...
Western Electric 753 variant is what I made. Altec 32 horn with a 6cuft cabinet. Sound is fabulous. Dynamic, smooth, room pressurizing bass.
There's a extensive thread here: https://hifihaven.org/index.php?threads/altec-2-way-build-ala-jelabs-802-32-414.3452/
Both 12" and 15" are discussed in detail.
There's a extensive thread here: https://hifihaven.org/index.php?threads/altec-2-way-build-ala-jelabs-802-32-414.3452/
Both 12" and 15" are discussed in detail.
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Thanks for the replies @waxx, @ogie, and @GM! Ogie, those cabinets are much more manageably sized than most other designs... I'll read through that thread you linked.
I have the N-500-G crossover, but it at least needs to be recapped and the rotary switch needs to be replaced... I was thinking I would just start from scratch unless there is some unobtainium magic that I should preserve there. The 511B horns leave a very small sweet spot in my experience, and I am hoping to get a broader sweet spot if possible...
Do you know if there were significant production differences in 416A coming out of the factory different years?
I have the N-500-G crossover, but it at least needs to be recapped and the rotary switch needs to be replaced... I was thinking I would just start from scratch unless there is some unobtainium magic that I should preserve there. The 511B horns leave a very small sweet spot in my experience, and I am hoping to get a broader sweet spot if possible...
Do you know if there were significant production differences in 416A coming out of the factory different years?
FYI/FWIW, the popularity of the M19 is primarily due to its XO that negates the 811's expo horn expansion's 'honk', lifts up its rolled off HF, but only works properly if the horn, woofer vertical spacing, cab width is maintained plus many space them up or tilt them back, so some informed DIYers have been doing column/tower/MLTL versions to suit, often tuning to Fs to take advantage of the extra net volume [Vb], better blend to the room.
Indeed, of the vintage designs this is by far the most 'HIFI' performing of the bunch, though to my ears only if driven with a period correct matching impedance SET amp or similar.
That said, the 416A is a re-badged 803B designed for the 12.56 ft^3 [net] 825 horn cab tuned to ~62 Hz (~40 Hz or sealed/HIFI), so ideally sealed for 6 ft^3.
You're welcome!
As for the 'unobtainium magic', this is to a great extent dependent on whether or not it's driven with period correct electronics or not, so assuming not, it takes a significant amount of tweaking to make it ~suitable for modern HIFI apps, so as much as I've enjoyed my various 511s, can't in good faith recommend them to anyone much younger than regular retirees without at least using DSP for XOs, frequency shaping plus significant horn bell damping and a larger version of the later 811 horn speaker's foam surround used to quell the mass quantities of eigenmodes that causes all the reflections back to the throat, modulating the driver (pass band response 'ripple').
As for any 'rising on axis' horn design, a super tweeter is your only viable option with a ~ 3 - 8 kHz XO point/slope to 'taste' 😉.
Early on, no, but over time due to various reasons there was a significant shift for the worst as forum member Pano found out the hard/expensive way with some GPA re-rebuilds, so recommend doing full T/S measurements before wasting another minute pursuing this project and FWIW/YMMV, ditto any Altecs before GPA's own versions, switching instead to modern (prosound) brands/models designed in ~ the performance parameters of truly vintage W.E./Lansing/Altec drivers.
These around 99db, so, yes tubes are the way to go. For the music I like and room size, 20 watts seems to get the job done controlling the 15" woofer.
I'm in the market for a SET amp as well, but if you only have one amp, I would recommend 20 watts.
BTW... dump the old Altec XO'ers and build a simple linkwitz XO with quality components.
Ok, I'm glad it isn't heretical to feel like the old XO is a weak link in the system.
I've actually been using a very nice headphone amp to power the speakers, and the 3ish watts are more than enough for me to hear why people classify these components as nearly end-game quality. The realism is uncanny.
Yeah, the XOs were basically just to protect the drivers under the assumption that they will either be hooked up to a proper prosound system or a HIFI system with proper LF/HF tone controls.
Wel, a friend is using Sofia Electric 91-01 amps (300B SET giving 7 watts) to drive his A7 system with the 416-8B and the 288 tweeter in 1505B horns. He has the N500 crossover, but only kept the front plate and let someone design a better crossover for it. But that amp is more than enough for his space that is quiet big (a big loft)
The bass cabinet is bigger along with some horn qualities which add a bit of help with the woofer. They also roll off around 50Hz.
Even though... I still think 20 watts would be better (especially for direct radiator) although for a SET lover, they may not decide to make the trade off.
