Altec 414 woofers

[airdronian]

I don't see much of these advertised around here. Are Altec 414-16c worthy for Haven members - in what looks like less than perfect shape ?





The ask is $170 obo. I wouldn't use them myself, but know people (at arms length) who do.

 

[Audionut]

That’s a heck of a deal assuming the voice coil’s are not shot. Short of being mint I would always send a set to GPA to give them the once over.
Ohh, and

 

[mhardy6647]

I wouldn't wonder that the baskets are worth that kind of gelt.

 

[airdronian]

This is why I ask questions. I've made an inquiry but am not entirely hopeful, this is Kijiji after all. But still, ya never know.

 

[joe83]

I think the C are ceramic so not as desireable as the others

Edit: as below i was wrong and C are not ceramic

 

[Roscoe65]

That’s is not correct. The C are Alnico in the cast pots. The 414E are ceramic.

414Z = Alinico, rear-mounting frame, welded magnet pot, 16ohms
414A = 414Z with magnet cover
414B = 414A but 8 ohms.
414-8B = 414B with new cast frame
414-8C = 414-8B with cast magnet pot. The 414C is 3 db less efficient than the 414A.
414-16C = 414-8C in 16 ohms
414-8E = 414-8C with ceramic magnet. No magnet return pot
414-16E = 414=8E IN 16 ohms.

 

[je2a3]

That’s is not correct. The C are Alnico in the cast pots. The 414E are ceramic.

414Z = Alinico, rear-mounting frame, welded magnet pot, 16ohms
414A = 414Z with magnet cover
414B = 414A but 8 ohms.
414-8B = 414B with new cast frame
414-8C = 414-8B with cast magnet pot. The 414C is 3 db less efficient than the 414A.
414-16C = 414-8C in 16 ohms
414-8E = 414-8C with ceramic magnet. No magnet return pot
414-16E = 414=8E IN 16 ohms.

I've only had experience with the 414A/414Z and 414-16B.

This is great info!

Thanks for posting, Roscoe!

 

[Roscoe65]

I personally own 2 pair of 414A and one pair of 414-8C. My factory 614 cabinets are the later, particle board models with a fixed cabinet back. I can only use my 414-8C’s mounted from the front.

 

[jt23]

@Roscoe65 - I was looking at your list of the different 414 models, and just wanted to confirm: the 414-8B has the same efficiency as the 414A/B/Z? I.e. the reason the 414C varieties are less efficient is due to the cast magnet pot?

Apologies in advance if it's a slightly redundant question!

 

[Roscoe65]

I believe the difference may be the cone or voice coil. The 414B has the cast frame of the 414C with the welded magnet pot and cover of the 414A. I suspect that the 414-8B might have the same efficiency as the 414-8C, about 3dB lower than the 414A/Z. The latter is reputed to have a more rising response (Altec Model 15 project). If anyone can tell me how a rising response would affect relative sound of the drivers I’m all ears.

I know that the 414-8B was used in the 9849A/D monitors. I believe that later models used the 414-8C. I believe both used the 32343 network.

Edit to add: I note that the Altec specifications for the 414A/Z includes of a magnetic flux of 10,000 guass, whereas the 414C specification is 9,000 gauss. The reduced magnet strength implies the lower efficiency of the later speaker. I suspect that the 414B has the weaker magnet of the 414C along with the new frame but the welded magnet pot and steel cover of the 414A. I do not know if there is a difference in the cone materials or specs. My 414A’s are packed up right now so I can do a visual comparison of the cones.

 

[jt23]

Thanks for the further details. Though not the answer I was hoping for! There'll definitely be lingering interest in the A/Z for me based on your comments; I'll have to wait for one to become available in the usual places. On the bright side, it could be interesting comparing either with the 414-8B I have on hand. One day perhaps...

 

[Roscoe65]

I’m beginning to suspect that one may not be better than the other, but the end use determines what may be mor suitable.

Based on the previously linked graphs for the 414Z vs. 414B, I would hesitate to use the 414B or 414C with a Joe Roberts style single cap crossover. Purely looking at the graphs, the 414Z has a rising response that roll off more smoothly. The 414B has a flatter response that does not roll off as smoothly at the top (but still smooth enough to use w/out filter if necessary.

The principal differences between the 414A/Z and the 414B/C is the frame, with the latter drivers using the later “416b-style frame) that can mount from the front or rear, and a smaller magnet (9,000 gauss vs. 10,000 gauss of the earlier drivers). Additionally, the default impedance of the later drivers becomes 8 ohms instead of 16 ohms. Out of curiosity, I compared the Altec 416 evolution. The change from 416A to 416B involved a similar evolution: the 15” rear-mount frame was replaced bye a 16” front mounted frame and the magnet flux reduced from 12,000 gauss to 11,000 gauss. Impedance was again default 8 ohms. The 416B also used the cast magnet return pot that was later used in the 414C.

Another interesting contrast between the 414A and 414B is the power rating: the earlier driver is rated for 25 watts continuous with the later driver rated at 50 watts continuous.

 

[je2a3]

I just did an informal ear test of my 414-16B vs. 414A, the 414A does sound slightly more extended in the upper mids and a tad more efficient. The 414-16B cone "feels" slightly heavier. It's still an excellent driver to my ears, just have to fine tune the crossover to use it properly.

 

[Roscoe65]

You must be reading my mind JE. I hypothesized that the cone was heavier in the later model, borne out by the difference in "feel" of the two cones, the way the 414B was prescribed in the 9842 using tuned ports instead of a simple port in the 614, and the parallel evolution of other Altec drivers, including the 855. Following the path from the WE 855A to the Altec 855E sees the driver morph from an ultralight, ultra high quality speaker (WE855A, WE728A), to the slightly lesser Altec direct equivalent (855A, 414A), to a slightly coarser, less efficient alnico model (855C, 414B/C) to a ceramic version (855E, 414E).

I 414A is more efficient but has a rising response. Its extra efficiency seems to be largely expressed from 1,000 to 4,000 hz. I would expect the bass to suffer in comparison to the heavier driver. I would also expect tube amps with low damping factors to get more bass bloom out of this driver.

The later driver was designed when low power was not the norm (as opposed to the 414A, when 10 watts was still a lot). It has twice the power handling and what appears to be a flatter response. The 32343 crossover uses equalization to extend the highs in the 9842. It actually takes a lot of attenuation to bring the upper mids down to the HF level. For those who enjoy flat frequency response, the lower efficiency of the 414B/C is an advantage since we can bring the HF driver down another 3dB. I also suspect that the driver sounds better with the two 6" d x 3" dia ports than the single 7" x 2" of the 614 cabinet. Interestingly, the port area of the 614 port and the combined 9842 ports are the same.

I think if I were using a SET I would prefer the 414A. If I were using something with a bit more meaty and modern sounding I would probably prefer the 414C with an upgraded 32343 crossover, maybe without the zobel, maybe with.

 

[je2a3]

I agree with your WE/Altec 755A>755C>755E evolution analogy. The ferrite 755C does seem to have slightly more perceived bass, but less midrange "snap" and treble air than its alnico predecessor.

You were probably pertaining to the Altec 9849-8B crossover with the sharper EQ + Zobel (discussed by @Salectric in this thread)? As @Salectric suggested, that XO + EQ was designed for the later black framed 414-8B or C + 8 ohm diaphragm or the rare 23744.

 

[Roscoe65]

Correct. That is the 32343 network - I have a pair.

Edit: Actually Je2a3, its was this thread: Altec 2 Way Build ala JELabs - 802/32/414. The thread you linked was for his modification for use with the Jensen P15LL.

The general advice seems to be to eliminate the Zobel. I suppose it is easy enough to disconnect or reconnect. I have the parts to build my own version of the 32343 using upgraded parts. Copper foil inductors, Oil caps, WW resistors. I have a pair of factory 32343 crossovers just for the HF choke Salectric says sounds best. I might also borrow a trick from him and use silver wire for the HF section.

I’ve also got an pair of Werner’s autoformers custom wound for 1dB steps instead of an l-pad. Because this wreaks havoc with the impedance the HP filter sees, Joe recommended using a shut resistor to provide a stable impedance for the filter. Werner also does this using a variable resistor.

Since I’m using an 8 ohm driver, I can turn it into a 16 ohm network by changing the shunt resistor value.

 

[je2a3]

Edit: Actually Je2a3, its was this thread: Altec 2 Way Build ala JELabs - 802/32/414. The thread you linked was for his modification for use with the Jensen P15LL.

Noted, thanks!

 

[Roscoe65]

That Altec 2 way thread should be required reading for anyone thinking about using the 802 and 32A horn.

 

[Freejazz00]

I know this is reviving an older thread, but here goes: how would an 802d match with a 414-16c? I imagine that the crossover would be rather simple considering they are both 16 ohm drivers. My concern was for the mismatch in the efficiency. Thoughts? Thanks

 

[Roscoe65]

The efficiency mismatch works in your favor. The 414-16C is about 96dB efficient and from response curves I’ve seen online is pretty flat from 500hz to 4,000hz. It is similar to the 414-8C or 8B used in the 9849. That speaker used the 23746 driver which is magnetically identical to the 806. The 802 is otherwise identical except it has a larger magnet and is about 2dB more efficient. Since the compression drivers are 109 and 111 dB efficient, we need to pad down the output under nearly all circumstances. We typically see this using the J-Rob Method of single cap brought in at 6-8Khz (spread 1st order with natural rolloff of main driver) To balance the natural falling HF response of the 806 or 802, or by using an equalization network on the HF driver like the @je2a3 crossover or the 32343 crossover used in the 9849. In this case, you want as much excess gain as possible from the HF driver. You are equalizing the HF output to match the 96dB output of the 414-16C. The 802 gives you that little extra on top that can extend your high end.