ALTEC A7 & 300B SET

[Steve Burger]

I believe the new Iconic 164 driver may be the best choice to achieve what you are aiming for. It has the low bass of the 416 but the sensitivity of the 515. I think that even with the 828 box you are going to be able to get below 40 hz with the 164.

[beto2]

Originally posted by Steve Burger:
[QB]I believe the new Iconic 164 driver may be the best choice to achieve what you are aiming for. It has the low bass of the 416 but the sensitivity of the 515. QB]

<font size="2" face="Verdana, Helvetica, sans-serif">Thank you Steve for your comments.
I will get some info about this driver.
Maybe the hard thing to resolve will be the short throw of my room. I need something like the Studio Near Field speakers..... I have read something about Hiraga crossover. Maybe the solution will be a mix of solution, but I think there are some others audiophiles with the same problem.
Regards,
Beto

[billfort]

3.5m x 5m (11.4? x 16.4?) is a small room ? particularly for partially horn loaded speakers like Altecs. In the past I used Model-19?s and 604-8G?s (9ft3 vented boxes) in almost an identical size room and feel the 604 co-ax was way better suited to that small space. I?ve heard A7?s in a room a little bigger than yours and didn?t even like them as much as the 19?s ? way too much speaker for a small space where you are sitting a few feet away. When I heard them in a much larger room, maybe 30? x 40? they sounded great but even in that space they where better the farther you got back from them.

A very personal taste sort of thing but I find large horn/large woofer speakers need some space to really gel and sound cohesive where the co-ax 604?s seem to work pretty good nearfield. Between the A7 which was designed for movie houses and the 19, I?d definitely pick the 19 for a largish domestic room but for a small space, I?d look into the 604, a speaker designed to work in studio monitor situations ? much more like your room.

All these observations by the way, where in systems using tubes, mostly low power SET stuff.

For an investment this big in time and money, I?d try real hard to listen to your options in a similar small room before doing something like buying piles of 515?s, vintage alnico compression drivers, 511 horns, etc., etc.. Your room is a MAJOR component in the final system and shoe-horning the wrong speaker in there may just be a big disappointment.

[beto2]

Originally posted by billfort:
[QB]In the past I used Model-19?s and 604-8G?s (9ft3 vented boxes) in almost an identical size room and feel the 604 co-ax was way better suited to that small space.
the co-ax 604?s seem to work pretty good nearfield.
I?d look into the 604, a speaker designed to work in studio monitor situations ? much more like your room.

All these observations by the way, where in systems using tubes, mostly low power SET stuff.

QB]

<font size="2" face="Verdana, Helvetica, sans-serif">Hello Billfort, thank you very much for your advises. You are right, maybe the near field will be solved with an small enclosure/driver. 604 drver fits well as the 18 model enclosure?
Some guy want to sell me a pair of 601's, as I have know the previous version of the 604. Also with enclosure and with a 500hz crossover. As I know, model 18 has a 1200Hz crossover. There are too much fine tuning to take in consideration.
Can you tell me about alternatives enclosure thats fit well, in my context, with the 604 duplex?
Regards,
Beto

[billfort]

I wouldn?t call the 604 a small driver - it essentially uses a 416/515 series 15? woofer ? and I certainly prefer the G in a pretty large box (9ft3).

I don?t know anything about the 601 and my experience is limited to the 604-8G and 604E, both of which I have spent a bunch of time with and heard in different cabinets. I preferred both these drivers in 9ft3/40Hz tuned cabinets with wide front baffles, one a direct copy of the 620A and the other a variation of the 620A I came up with maintaining the 620?s size/tuning/baffle width but raising the driver to ear level and beveling the rear corners to accommodate corner placement.

They may not look as pretty as a narrower, smaller speaker but I think they sound best in a 620 style box if you are looking for something full range. Here?s a picture of the cabinets I built for my G?s in my new room (12.2? x 22.6?), a little bigger than my previous space. They work great in this room and the 45 SET (center of picture) seems quite adequate driving them, although the 300B?s (in front of speakers) sure sound nice if I want real big dynamics.



I am building a pair of larger horn Altecs (416-8A/902/round wood 400Hz tractrix) to try as well because I think this room may be big enough for them but I?ll never give up the 604?s, they just work so nice in typical listening rooms.

If you are interested in more detail on the cabinets I built, you can find it here .

[beto2]

Originally posted by GM:
A driver does not 'throw' LF because it cannot confine it and the WLs are so long that in a typical room you are in its nearfield.

<font size="2" face="Verdana, Helvetica, sans-serif">Hi GM, thanks for sharing your proyect. Do you have some experience with 604 duplex speakers? Maybe the direct comparition between Duplex vs two drivers, comparing bass extension, mids and highs in an small room, maybe will solve the dilema. Now I'm researching, but then I have to decide on one system. My experience was with the A7 and I love it, but as you and all are saying, my listening room is small.
At all events,thanks all of your comments, now I'm very close to the solution.
Is the time to find the right drivers, here in Chile. There are a few on old teathers, or in old auidiophiles houses, etc., and tubes here are still very marginal, so prices are a bit down comparing with U.S.A. Also I'm considering to buy on the States, Ebay or something, but shipping cost is an issue, because they are heavy weight dreams!
Regards,
Beto

[beto2]

[QUOTE]Originally posted by billfort:
They may not look as pretty as a narrower, smaller speaker but I think they sound best in a 620 style box if you are looking for something full range. Here?s a picture of the cabinets I built for my G?s in my new room (12.2? x 22.6?), a little bigger than my previous space. They work great in this room and the 45 SET (center of picture) seems quite adequate driving them, although the 300B?s (in front of speakers) sure sound nice if I want real big dynamics.
QUOTE]
Thank you very much Billfort. You have a very nice and informative site. I'm very lucky finding people like all of you, sharing your experiences.
Do you something about the Hiraga crossover? As I have read was designed to match the A7 in small rooms (house use). I don't know if this kind of solution will be functional, maybe is like to caress a cat at the wrong side and there are a "natural" solution.
Regards,
Beto

[GM]

Greets!

You are welcome! Some. As I've already stated, I prefer a large horn/LF drivers in a typical Hi-Fi/HT app. Coincident (AKA duplex, coaxial) drivers are best suited to nearfield apps IMO, but as always YMMV.

Since you consider the A7's stepped response an acceptable trade-off to get its midbass dynamics and have concerns for your relatively close listening distance, and combined with your lack of desire to afford extra drivers at this time, I recommend sticking a 604 into an A7 cab, experimenting with tuning it lower and/or reducing its Vb with bag(s) of either kitty litter or sterilized sand, damping the inside top of the horn and doing all the usual cab tweaks. With no HF horn mount/brace on top, either a second layer or a mouth brace needs to be added also.

GM

[beto2]

Hi GM,
from know I'm absorbing all this knowledge to measure the problem. As I have read and based on the experts experience, Duplex 604 seems to be a really good alternative. However, A7 system is on my mind also, because if in the future I can modify/supress some circulation on my living room (actually isn't rational/functional, hahaha, it is not my design), I will place my equipment on the small side of the rectangle, so I will get at least 5 meters throw, with just 1 place (mine) in front of them. But, now this is only a though.
Thank you for your advices.
By the way, do you know the cost for a pair of 604 duplex, remagg.?
Regards,
Beto

[beto2]

Originally posted by billfort:

I preferred both these drivers in 9ft3/40Hz tuned cabinets with wide front baffles, one a direct copy of the 620A and the other a variation of the 620A I came up with maintaining the 620?s size/tuning/baffle width but raising the driver to ear level and beveling the rear corners to accommodate corner placement.

<font size="2" face="Verdana, Helvetica, sans-serif">Hi Billfort, do you think that your new corner design will work well if I have placed them not on the corners? Because I have use the large side of the rectangle for place my equipment, so corners ar far.Wich parameters will I have to know to calculate any modification on tuning the baffle? Also, do you know important differences between 604 models? Thanks a lot in advance.
Regards,
Beto