FYI, the last selling price of those speakers was $60k. Granted, they are the field coil version, but still...
Anthony, Your MJK simulations look correct, and a 60" line length with 14.5cuft should pull the maximum deep bass from this driver. A few thoughtful construction details might create "Big is Beautiful" furniture for your living room instead of the "2001 Black Monolith".
Early Thanksgiving joke --- If you do not cleverly stuff this big box you could get a Turkey. Your MJK simulation models a uniform 0.25 lb/cuft density, and I believe MJK's model assumes Polyfill stuffing. The 16" Altec-604 cone is required to cover ~30Hz - 15kHz, and some designers vary the stuffing density(stuffing methods) along the line in an attempt to keep a "beautiful high" going as long as possible. I am not sure a simulator can prove the sonic benefits, but only show the rocky SPL bumps from under-stuffing. Any TL stuffing experts here?
I'm still feeling some audio love for the sealed Altec-604 + ported JBL 2235H. 😀
Early Thanksgiving joke --- If you do not cleverly stuff this big box you could get a Turkey. Your MJK simulation models a uniform 0.25 lb/cuft density, and I believe MJK's model assumes Polyfill stuffing. The 16" Altec-604 cone is required to cover ~30Hz - 15kHz, and some designers vary the stuffing density(stuffing methods) along the line in an attempt to keep a "beautiful high" going as long as possible. I am not sure a simulator can prove the sonic benefits, but only show the rocky SPL bumps from under-stuffing. Any TL stuffing experts here?
I'm still feeling some audio love for the sealed Altec-604 + ported JBL 2235H. 😀
Ya think?! 😉
Wish I had access to all my old stuff; back in the basslist days I did a 36"W x 72"H x 24"D cab design [MLTL nowadays] loaded with a 604E and [3] 2235H, [1] for mid-bass, [2] for bass. Wish I could of auditioned them, but he was somewhere up in the Northwest and not long after completion he dropped off the 'map', not returning my emails, etc..
Over the years I've kept on the lookout for them since he wasn't particularly young judging by a photo of him standing beside one. Hate to think they got gutted for parts, but the cabs were massively built like mine with a braced 2x4 frame like one builds a house and 2x6 framing to mount all the individual drivers and sheathed with 3/4" no-void marine grade plywood.
Here's a Japan spec studio monitor with 604, 416 and super tweeter that coupled to a Dr. Geddes' style multiple sub system would do the largest pipe organ symphonies, movie LFE loud enough for most folks: ALTEC LANSING 6041Monitor??? ?????
Noisy ports, excellent driver damping was normally dealt with either with tube amp tone controls and/or by covering the back of the driver with damping and/or critically damping the vent [what I used and Altec, RCA recommended, while JBL, Frazier, Heathkit used lots of cab damping/stuffing in the cabs I've seen].
GM
Greets!
Indeed it does and at ~0.25 lbs/ft^3 the closest I could figure out polyfil stuffing damped ~the same as the 1" acoustic fiberglass insulation [O-C 703 ductboard] I use/recommend attached to the top, one side, back [Altec's basic recommendation, though in a MLTL just to down around 70% of its path-length IME], though a number of folks [particularly the 'FR' driver alignments] said that it was way too much polyfil, so as always YMMV.
One gentleman in particular with a SET tube driven 311-90/TAD, 515B Vb = Vas, Fb = Fs ~27 ft^3? MLTL [well braced including motor, 1" marine grade IIRC] removed all of the damping except for one thick felt pad [IIRC] on the back behind the driver, saying he and his wife could discern no 'hollow' sound whatsoever after critically damping the vent.
Speaker stuffing density is so room, system, speaker construction and especially personal preference, dependent that I don't think anyone can be an 'expert' since in room it boils down to the latter [read the female's if there's any to consider].
Personally, the only time I use stuffing is for ~aperiodic loading or need a wad of Miraflex or FG to 'plug' a zero terminated pipe [to a point, such as the BIB pipe horn]; otherwise just enough lining to quell any 'hollow' sound and reflections back through the diaphragm, then if required, critically damping the vent with layer
GM
I guess I'll have to stuff cleverly because I wouldn't know what to do with the turkey. I'm a vegetarian. LOL but I do like the Joke.😀
You're not the only one feeling audio love for the "Lansing Towers" as we called them. My goodness they even had a name. I'm getting some heat from a family member here for disturbing the system. For some reason in this hobby/obsession interest what is it? You always think you could make it better. I became interested in the Altec 604 plus an Altec system marketed in Japan, read post by GM and others over at the Altec forum and with some guidance from Zilch "RIP" I put together the Lansing Towers. Here is what they looked like.
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There you go! The Altec Lansing 6041 Monitor. When i first saw these I started loosing sleep this led to my Lansing towers 604-8H in 4705 JBL cabs stock crossover. "I still have these". JBL 2235 in 4705 cabs, active Marchand xm9 crossover crossed at 350HZ Lo out to Mc352 to JBL2235, Hi out to Mc275 to stock 604 crossover.😕
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Wish I still had my MC275 and MC500; sold a '56 AH for the former and later a '62 AH to buy the latter, but at the time I was newly captivated by bi-amping w/digital EQ, XOs, so something with excellent resale value had to go and it wasn't going to be the Porsche, though hindsight being 20-20, I chose wrong 'big time'. 🙁
I've built many 'el cheapo' 1.5 way systems with most being a car audio 'FR' driver on the wall or shelf with the 'helper' [mid-bass] woofer on the floor and they really are the best bang/buck performers IME, so only makes sense to do it with premium drivers too, especially when limited floor space is an issue.
GM
I've built many 'el cheapo' 1.5 way systems with most being a car audio 'FR' driver on the wall or shelf with the 'helper' [mid-bass] woofer on the floor and they really are the best bang/buck performers IME, so only makes sense to do it with premium drivers too, especially when limited floor space is an issue.
GM
I guess we all have changed parts of our system then look back and say maybe i should not have done that. Should have listened to my wife she kept telling me."If it not broken don't fix it". However, It should not be too difficult to rebuild this system i will have to locate a pair of 2235's. I have the top cabinets complete I'll have to convert them to sealed cabs. I still have the amps/active crossover. I can build a pair of 4507 cabinets I have the material. I wonder if I can upgrade the low end. Huh.🙂 I do thank you all for steering me in the right direction even if it meant having to make a U turn.
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Great thread! Lots of great details. I built an MLTL cabinet couple of years ago for GPA 604-8H III based using the following spec (L= 42.5",W=24 1/8", D =17 11/16", Vent = 6" dia X 2" long and CSA = 422.04"^2) and 9-1/4" raised up from the floor. It came out really well, I was using with low powered SET amps 45/2A3/300B. This was probably the best setup I had so far. I am not a speaker designer or technical expert by any means.
Thanks for sharing the dimensions - 60"x26"x19" O.D. (HxWxD} CSA = 428.75 sq.in. Internal Vol. = 14.5 cu. Ft.
Thanks for sharing the dimensions - 60"x26"x19" O.D. (HxWxD} CSA = 428.75 sq.in. Internal Vol. = 14.5 cu. Ft.
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If your Altec 604-8H has the below T/S parameters, then sealed 3cuft ~ 0.7Qtc and sealed 5cuft ~0.6Qtc. My ears would probably favor the 0.6Qtc with Fiberglass(2" 705 board, or Formadehyde free 3.5" batts) lining all 5-sides. IF your ACTIVE CROSSOVER only supports basic "block function(LR2/LR4/BW3)", then a sealed 3cuft with 0.7Qtc will allow a more exact Xover slope match. To experiment with 3cuft, you might screw in wood blocks before mounting the Altec 604.
Altec 604-8H
Xmax 0.15 (inch)
Re (ohms) 6.50
Vd 19.20 (cu. in.)
Fs 28.10
Vas 19.73
Qts 0.27
Qms 7.10
Qes 0.28
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Basic Bass question #1: What box dimensions and internal volume is desirable? acceptable?
Basic Bass question #2:
--do you have high functionality DSP equalizer + microphone + complex crossover functionality;
--or more basic "block function(LR2/LR4/BW3)" active Xover hardware?
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If you plan to use high functionality DSP plus a high wattage amplifier, then a Musical(modest Mms, low Le, Qts 0.3-0.35) 18" woofer in your planned modest volume (~6cuft) sealed box becomes attractive. AcouticElegance TD18H; Faital 18FH510; JBL 2242H; low cost Peavey LoRider18; etc... You can build additional equalized "swarm" woofers if you enjoy these speakers.
If you plan to use a basic block-function(LR2/LR4/BW3) active Xover, then a musical 15" woofer in a ~6cuft ported cabinet becomes attractive. Give up some deep bass for simple ported efficiency. Acoustic Elegance TD15S, JBL 2235H; low cost Peavey LowRider 15; etc..
I love the 604...and I've built three large cabinets for different applications, including:
Stonehenge (unofficial V), using nice Palesander veneer over one inch birch ply.
Shindo shape cab with volume same as 620. 416 woofer and JBL clone horn.
250 liter double walled Walnut cab for my existing project, with 420A driver.
Stonehenge (unofficial V), using nice Palesander veneer over one inch birch ply.
Shindo shape cab with volume same as 620. 416 woofer and JBL clone horn.
250 liter double walled Walnut cab for my existing project, with 420A driver.
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atilsley,
Do you have any experience with putting an Altec Alnico 604-8 in a sealed cabinet, and adding a real-woofer to suplement the bass?
Any information on sealed vs. ported, crossovers ckts, frequency/slope, woofer selection, etc... which could help Mister_T ?
I have Peavey LoRider 18" sealed woofers, and Acoustic Elegance TD15S ported woofers which sound very different in my room, and I am not in the position to recommend which would best blend with the Altec 604.
Linesource
The xovers I've used for the above three were:
Stonehenge, GPA 1,600Hz
620 Box, can't remember, sorry
420A, two types used...Altec 800 and a custom 1,600Hz, 24db LR
I like the notion of using a second altec bass driver with the 604....sort of keeping things in the family. That doesn't mean it's the best though...although I think the speed of a 416, for example, would be ideally matched to the 604....given they're similar drivers.
The most immediate question then becomes, 'shouldn't you use something bigger/'better' than the 604 woofer?' Yes and no.
However, I would use MiniDSP or some other form of active netword for the bass woofer only....this way the gent can have his cake and eat it too. You can then get away with a reasonably sized ported cab for the bass...and a matching box on the top for the 604.
Two gloss black boxes, separated by rubber/felt feet. Nice.
Of the bass drivers you suggested, I'd go with AE...they have a very good wrap.
Of course, he would need a separate amp for the bass. Signal wise, use a $5 gold T RCA splitter from the preamp to Minidsp for the bass amp.
Oh, I forgot, I've built another Altec cab for 416...about 150 liters. See pic.
The xovers I've used for the above three were:
Stonehenge, GPA 1,600Hz
620 Box, can't remember, sorry
420A, two types used...Altec 800 and a custom 1,600Hz, 24db LR
I like the notion of using a second altec bass driver with the 604....sort of keeping things in the family. That doesn't mean it's the best though...although I think the speed of a 416, for example, would be ideally matched to the 604....given they're similar drivers.
The most immediate question then becomes, 'shouldn't you use something bigger/'better' than the 604 woofer?' Yes and no.
However, I would use MiniDSP or some other form of active netword for the bass woofer only....this way the gent can have his cake and eat it too. You can then get away with a reasonably sized ported cab for the bass...and a matching box on the top for the 604.
Two gloss black boxes, separated by rubber/felt feet. Nice.
Of the bass drivers you suggested, I'd go with AE...they have a very good wrap.
Of course, he would need a separate amp for the bass. Signal wise, use a $5 gold T RCA splitter from the preamp to Minidsp for the bass amp.
Oh, I forgot, I've built another Altec cab for 416...about 150 liters. See pic.
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8 cuft cabinet volume seems to be the starting size for an efficient 15"-18" ported woofer. Mister_T will need determine what can fit into his listening room.
The GPA 515-LF is often used as the woofer for Altec speakers. Often in a front horn. In a simple 8cuft ported cabinet tuned to 32Hz it produces a modest drop bass-shelf alignment which usually combines well with near-wall room gain into a reasonably flat SPL.
From your experience, would the GPA 515-LF be a good woofer match for the Altec 604-8H? "Altec family sound, no horns required"
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I haven't used the 515-LF driver...but if it's purpose built for what we're talking about, then I would be very comfortable recommending it.
As to the 8cuft size, I'd only agree with that if that was the requisite size to get the best out of the 515-LF. The issue is not about cabinet size for the 604...that can be 2-3 cubic foot for this purpose...as the "mid" bass driver will have no need to go low....maybe 150Hz.
As I wrote earlier, you then have to decide re how to drive the lower woofer. If passive, then yes, a larger box needed.
I built with 604-8K, I am not sure how much of a difference there is compared to the “H-version”. Outer dim 1020 x 520 x 400 mm, internal volume about 141 L / 5,0 ft³ after element and bracing. Roughly 162 L / 5,7 ft³ virtual volume after 30 mm of 96 kg/m³ of glass wool sheets (equivalent to OC705) along walls and remaining volume fully stuffed with 13 kg/m³ glass wool.
They turned out sounding really nice and dynamic but “bass shy”. Not a problem really, as they were backed up with 2 separate subs. Bought them as NOS together with original filters about 10 years ago. They are now being replaced with some other DIY speakers and will be put in the den as TV speakers or used as surround speakers. Getting rid of them? No!
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Good Day,
LineSource - I am well into the process of reverting to my dual cabinet system comprising of stacked JBL 4507’s. In my previous system I have used 604's in the 4507 all vents open (tuning Freq. 40 Hz). WinISD SPL curve -3.0db at 96.79. In previous post your suggestions of a sealed enclosures look interesting, SPL curve showing -3.0db at 100 Hz is close to the vented cab but in this case it not that critical. However, the sealed cabinet eliminates having four ports around the 604 this looks like a major improvement.
I use a Marchand xm9 crossover it has LR high and Low outputs. Presently I use a crossover point of 350 Hz to the low LR channel power amp and the High LR power amp gets signals above 350Hz into the 604 passive crossover that has a 1500Hz xover point.
Lower cabinets: I will be using JBL 4647a cabinets (4507 cabs with 2226H woofers) I recently found a pair pretty close to home. The price was right and they are in good condition. I have seen mixed reviews about the 2226H woofer. The 2235H is always rated highly. However, I have a SVS sealed 12 in sub I can tune low ~ 50-60Hz to complement the 2226h.
“--do you have high functionality DSP equalizer + microphone”
No I do not. I have been using my air so far but at some point I will have to get a better understanding of room analysis and the use of DSP systems.
Other members have been posting drawings and different cabinet designs they have used for the Altec 604 makes viewing the thread interesting. Eye Candy, food for thought. It's all very informative. Thanks😀