I know of at least one 604 user who likes that crossover ( used with his 8 ohm, GPA modified 604e's ).
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Altec Fever!!
- Thread starter sanjib
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I know of at least one 604 user who likes that crossover ( used with his 8 ohm, GPA modified 604e's ).
Great! I will use it for now.I know of at least one 604 user who likes that crossover ( used with his 8 ohm, GPA modified 604e's ).
I don't think the seller has any experience with Altec. He mentioned GPA crossover as "German" crossover. From the pictures, I knew one had a GPA cone but had no idea about what was inside the HF diaphragm.
Thank you! I can reverse-engineer the schematic, but I don't have an inductance meter to measure the value of the inductors.
Bought a single $80 car subwoofer cabinet from Amazon to try out and made a few modifications. Currently, I am listening to a single speaker. I think 604-8G is a different animal!
The amount of bass response I am getting from this cabinet is enough for me. I will share the full experience when I finish the modifications of the other cabinet.
The amount of bass response I am getting from this cabinet is enough for me. I will share the full experience when I finish the modifications of the other cabinet.
I put 604-8Gs in mine today and was surprised at the depth of the bass just using the cabinet as is. Doing sweeps I heard useful bass at 35 cycles though I think it's down a few DB. Tomorrow I will probably measure and EQ them.
This is uncanny, I was looking at just that cabinet for a pair of university coaxials. Might have to pull the trigger now.
In the interest of accuracy, and with a bit of hesitation (cuz I'm not qualified to question any of you folks), I think the claimed 5.3cu' is based on exterior dimensions...
In the interest of accuracy, and with a bit of hesitation (cuz I'm not qualified to question any of you folks), I think the claimed 5.3cu' is based on exterior dimensions...
Yes, you are right. The internal volume is 4.2cuft. I am experimenting with the number of ports. Here is the latest one, 50 Hz tuning frequency with 3 circular ports of diameter 2.5 inch and you got a nice little bump in the low frequency region.
Plots of the 604-8Gs after EQing them with the DSP of my Acoustas amp. Bump in bass is persistent, might be room, might be box's existing vent which I haven't yet fiddled with. Extended bass came from raising EQ below roll off, generally a no-no with vented boxes. Sound is very good.
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@Tom Brennan
Great info. I have ordered just a single box to try out, and the second will come today. I will have a better assessment after putting 2 together! Just listening to one speaker, I think the box is working pretty well, and the GPA crossover is also very good.
Great info. I have ordered just a single box to try out, and the second will come today. I will have a better assessment after putting 2 together! Just listening to one speaker, I think the box is working pretty well, and the GPA crossover is also very good.
Both speakers are up and running. These cabinets are producing enough bass and sound great overall! They are doing some amazing things in respect of imaging and resolution, and it is hard to explain. I took a video with my Samsung phone with an in-built mic, but it does not do justice to what I am actually hearing. Anyway, I uploaded it to YouTube.
in several photos not only the metal bent, i notice solder bulging out which will not allow the voice coil to move correctly id replace both voice coils so there will be no noticeable sound quality difference. if you have 8 ohm id get them 8 ohm stay away from stainless steel ones, go to GPA and send them the speakers they will magnetize , place new alum 8 ohm colis , check them out before sending them back to you. I have had several sets done by them you should have no problems other than having to wait for them to get back to you. someone used to many watts to heat them up and melt the coils by to much power.
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GPA has no voice coils. They no longer repair any Altecs.
In fact, I looked just yesterday, they seem to have no drivers for sale either.
Sanjib replaced both diaphragms with GPA parts he managed to source in Europe somewhere a while back.
thanks for the heads up, i don't like to give out wrong info much respect to ya for setting me straight.
BTW, the GPA is out of business for customers with vintage Altec. I found the Troy Audio bought them and selling Super Santana for €36000 a pair in Europe!