Embiggening the Altec 620. Thoughts/experiences with >9 cu ft cabs for Altec 604-8g?

What are you trying achieve with a 20 cuft cabinet? What are your likely constraints and challenges?

I considered a big BR cabinet for my GPA duplexes and decided on a MLTL (not exactly "narrow") designed specifically for my circumstances and needs. I'm glad I did.
 
What are you trying achieve with a 20 cuft cabinet? What are your likely constraints and challenges?

I considered a big BR cabinet for my GPA duplexes and decided on a MLTL (not exactly "narrow") designed specifically for my circumstances and needs. I'm glad I did.
It would take some really compelling evidence - anecdotal or otherwise - of the superiority of 20 cu ft cabs for me to consider something that big.

What I was hoping to find by starting this thread were impressions - whether good or bad - from folks who have owned or heard 604s in cabs bigger than 9 cu ft.

Realistically, ~12-13 cu ft is probably the biggest I could go for domestic purposes.

I think it was @John Frum who astutely pointed out that I may be best off in going with some well-constructed 620s (which my current cabinets are most definitely not).

I've no doubt a new pair of quality 620 cabs made from .75 or 1" baltic birch would sound better than my beat-up originals.

I've never heard 604s in MLTLs. I'd love to hear more about your build. My main reservation with MLTLs is with altering the tonality of LF from what I've gotten used to. Would love to hear a pair some day.
 
I’ve only heard GPA duplexes in my MLTL and a large, nicely executed Shindo inspired design. After hearing the Shindo, I chose a different path.

My build was the first pair of Scott Lindgren’s Bison design; I originally commissioned that design. They are a bit overbuilt, weighing in at roughly 100kg each. I can certainly understand concerns about tonality and general presentation. The MLTLs are relatively even and solid sounding, perhaps lacking a bit of mid bass punch/emphasis and the sort of hollow sound I hear in varying degrees with BR.

Disclaimer: I have not heard my drivers in a range of BR cabinets and can't be entirely sure of my opinions; YMMV.
 
Last edited:
Hello everyone !!

Long time lurker first time posting. I have a pair of original, excellent condition 604e’s that I got from a local radio station that I used to listen to as a kid. They came in small 6 cu ft 620 style cabs, 3/4 inch spruce ply which I used for a couple years. Switching to Werner crossovers and Dueland DCA 16 ga wire made them sound a lot more real and natural with added detail and colour. They turned the midrange and top end nasties into smooth music. Unfortunately they both take a fair bit of burning in before they sound their best.

For a Covid project I decided to build a Shindo clone cab with 1/2 inch Baltic birch and 5/8“ front panel. I made them an inch and a half taller to get the driver the height I wanted and look symmetrical in the top portion of the speaker. Half way through the build I got worried because they sounded like a big bass drum whenever I tapped or bumped them. I carried on regardless and could not be more pleased with the outcome.

To start, the new cabinets put out a lot more energy and lower bass into the room. It wasn’t boomy just more energy and lower bass than either me and my floor were used to. So it was really exciting the room and especially the floor which then carried over into the stand. I found a few loose floor joists in the subfloor and had to do a redo of isolation and stand and equipment supports. Finally with the sound fined tuned I was happy to proceed. I am still contemplating opening the ceiling in the basement to find the loose floor joists and properly secure them. The room is quite large at 34’ X 20’ and 14’ ceiling with 3/4“ hardwood flooring over 2 layers of 3/4” ply subfloor.

The sound with the new cabinets did a few things I wasn’t expecting. The soundstage was a little bigger, but more clearly spread out and organized, as if it was easier to look at and see everyone or thing more clearly. I should mention my old cabs were 23“ wide, the new ones are 27 1/2”. Dynamics were a little bit better also but with no limit to the volume I choose . Not that you hit a ceiling with the old cabs but with the new ones the music just swoops from soft to loud and sweeps you up along with it, so natural, they seem to have no limit.

We have my mom staying with us for awhile, she has stage 4 Alzheimer’s and used to play and teach piano, organ and accordion. I put on the Bill Evans Mosaic 80’s Vanguard session. “Nardis” where Bill has a solo at the start of each version, some of the most forceful playing I’ve ever heard from him. My mother has hearing aids and trouble hearing so I gave it lots of juice. She was air piano playing with pedals too, with the biggest smile on her face I’d seen in awhile. “ Boy !! He’s really playing !!! “ is what she said and I had to agree. It was also the most live and thrilling rendition of it I’ve heard, like we were sitting on the edge of the stage or the front row with those little round tables wrapped in terry cloth.

Another area I can’t explain is with the old cabs some peaks in the music or a horn or a voice when it can get a little sqauky or shrill for a second or two and you tense up knowing it’s coming, With the new cabinets, totally gone, smooth as silk, I still can’t figure that one out. The old cabs were solid as a rock and the drivers were solidly mounted.

And finally the bass, definitely goes lower in frequency than before, I’m not into measurements but it’s low enough that it tickles ones tush now where it didn’t with the old boxes and it flushes out the bottom octave of the standup bass on well recorded Jazz. It’s not like adding a big sub or anything but just filling in the bottom and maybe a touch more power in the bass on some recordings, a touch. You can also feel it in your stomach a little more on some records, not a huge difference but it’s there. I was maybe expecting the bass to be overdone with the boomy cabinets but it’s not, at least not in my room and with my equipment. They will teach you about your room and the stuff in it though, unless you’ve played with subs before. Definitely haven’t noticed any drawbacks of any kind. No loss of snap or any nasties I can think of. It’s all upside in my books.

ok enough for now,
 
Hello everyone !!

Long time lurker first time posting. I have a pair of original, excellent condition 604e’s that I got from a local radio station that I used to listen to as a kid. They came in small 6 cu ft 620 style cabs, 3/4 inch spruce ply which I used for a couple years. Switching to Werner crossovers and Dueland DCA 16 ga wire made them sound a lot more real and natural with added detail and colour. They turned the midrange and top end nasties into smooth music. Unfortunately they both take a fair bit of burning in before they sound their best.

For a Covid project I decided to build a Shindo clone cab with 1/2 inch Baltic birch and 5/8“ front panel. I made them an inch and a half taller to get the driver the height I wanted and look symmetrical in the top portion of the speaker. Half way through the build I got worried because they sounded like a big bass drum whenever I tapped or bumped them. I carried on regardless and could not be more pleased with the outcome.

To start, the new cabinets put out a lot more energy and lower bass into the room. It wasn’t boomy just more energy and lower bass than either me and my floor were used to. So it was really exciting the room and especially the floor which then carried over into the stand. I found a few loose floor joists in the subfloor and had to do a redo of isolation and stand and equipment supports. Finally with the sound fined tuned I was happy to proceed. I am still contemplating opening the ceiling in the basement to find the loose floor joists and properly secure them. The room is quite large at 34’ X 20’ and 14’ ceiling with 3/4“ hardwood flooring over 2 layers of 3/4” ply subfloor.

The sound with the new cabinets did a few things I wasn’t expecting. The soundstage was a little bigger, but more clearly spread out and organized, as if it was easier to look at and see everyone or thing more clearly. I should mention my old cabs were 23“ wide, the new ones are 27 1/2”. Dynamics were a little bit better also but with no limit to the volume I choose . Not that you hit a ceiling with the old cabs but with the new ones the music just swoops from soft to loud and sweeps you up along with it, so natural, they seem to have no limit.

We have my mom staying with us for awhile, she has stage 4 Alzheimer’s and used to play and teach piano, organ and accordion. I put on the Bill Evans Mosaic 80’s Vanguard session. “Nardis” where Bill has a solo at the start of each version, some of the most forceful playing I’ve ever heard from him. My mother has hearing aids and trouble hearing so I gave it lots of juice. She was air piano playing with pedals too, with the biggest smile on her face I’d seen in awhile. “ Boy !! He’s really playing !!! “ is what she said and I had to agree. It was also the most live and thrilling rendition of it I’ve heard, like we were sitting on the edge of the stage or the front row with those little round tables wrapped in terry cloth.

Another area I can’t explain is with the old cabs some peaks in the music or a horn or a voice when it can get a little sqauky or shrill for a second or two and you tense up knowing it’s coming, With the new cabinets, totally gone, smooth as silk, I still can’t figure that one out. The old cabs were solid as a rock and the drivers were solidly mounted.

And finally the bass, definitely goes lower in frequency than before, I’m not into measurements but it’s low enough that it tickles ones tush now where it didn’t with the old boxes and it flushes out the bottom octave of the standup bass on well recorded Jazz. It’s not like adding a big sub or anything but just filling in the bottom and maybe a touch more power in the bass on some recordings, a touch. You can also feel it in your stomach a little more on some records, not a huge difference but it’s there. I was maybe expecting the bass to be overdone with the boomy cabinets but it’s not, at least not in my room and with my equipment. They will teach you about your room and the stuff in it though, unless you’ve played with subs before. Definitely haven’t noticed any drawbacks of any kind. No loss of snap or any nasties I can think of. It’s all upside in my books.

ok enough for now,
What a great first post! Welcome to the Haven!

Any pics of these new cabs? I’m sitting on a pair of 604-8G’s and I’m weighing cabinet options and would love to see yours.

- Woody
 
Hello everyone !!

Long time lurker first time posting. I have a pair of original, excellent condition 604e’s that I got from a local radio station that I used to listen to as a kid. They came in small 6 cu ft 620 style cabs, 3/4 inch spruce ply which I used for a couple years. Switching to Werner crossovers and Dueland DCA 16 ga wire made them sound a lot more real and natural with added detail and colour. They turned the midrange and top end nasties into smooth music. Unfortunately they both take a fair bit of burning in before they sound their best.

For a Covid project I decided to build a Shindo clone cab with 1/2 inch Baltic birch and 5/8“ front panel. I made them an inch and a half taller to get the driver the height I wanted and look symmetrical in the top portion of the speaker. Half way through the build I got worried because they sounded like a big bass drum whenever I tapped or bumped them. I carried on regardless and could not be more pleased with the outcome.

To start, the new cabinets put out a lot more energy and lower bass into the room. It wasn’t boomy just more energy and lower bass than either me and my floor were used to. So it was really exciting the room and especially the floor which then carried over into the stand. I found a few loose floor joists in the subfloor and had to do a redo of isolation and stand and equipment supports. Finally with the sound fined tuned I was happy to proceed. I am still contemplating opening the ceiling in the basement to find the loose floor joists and properly secure them. The room is quite large at 34’ X 20’ and 14’ ceiling with 3/4“ hardwood flooring over 2 layers of 3/4” ply subfloor.

The sound with the new cabinets did a few things I wasn’t expecting. The soundstage was a little bigger, but more clearly spread out and organized, as if it was easier to look at and see everyone or thing more clearly. I should mention my old cabs were 23“ wide, the new ones are 27 1/2”. Dynamics were a little bit better also but with no limit to the volume I choose . Not that you hit a ceiling with the old cabs but with the new ones the music just swoops from soft to loud and sweeps you up along with it, so natural, they seem to have no limit.

We have my mom staying with us for awhile, she has stage 4 Alzheimer’s and used to play and teach piano, organ and accordion. I put on the Bill Evans Mosaic 80’s Vanguard session. “Nardis” where Bill has a solo at the start of each version, some of the most forceful playing I’ve ever heard from him. My mother has hearing aids and trouble hearing so I gave it lots of juice. She was air piano playing with pedals too, with the biggest smile on her face I’d seen in awhile. “ Boy !! He’s really playing !!! “ is what she said and I had to agree. It was also the most live and thrilling rendition of it I’ve heard, like we were sitting on the edge of the stage or the front row with those little round tables wrapped in terry cloth.

Another area I can’t explain is with the old cabs some peaks in the music or a horn or a voice when it can get a little sqauky or shrill for a second or two and you tense up knowing it’s coming, With the new cabinets, totally gone, smooth as silk, I still can’t figure that one out. The old cabs were solid as a rock and the drivers were solidly mounted.

And finally the bass, definitely goes lower in frequency than before, I’m not into measurements but it’s low enough that it tickles ones tush now where it didn’t with the old boxes and it flushes out the bottom octave of the standup bass on well recorded Jazz. It’s not like adding a big sub or anything but just filling in the bottom and maybe a touch more power in the bass on some recordings, a touch. You can also feel it in your stomach a little more on some records, not a huge difference but it’s there. I was maybe expecting the bass to be overdone with the boomy cabinets but it’s not, at least not in my room and with my equipment. They will teach you about your room and the stuff in it though, unless you’ve played with subs before. Definitely haven’t noticed any drawbacks of any kind. No loss of snap or any nasties I can think of. It’s all upside in my books.

ok enough for now,
Agreed on the great first post. I’m a 604e fan for life too. I am never parting with mine. Can’t wait to read up more on your setup and see some pics. Feel free to drop by the member intro thread.
 
Very nice @Recordboy ! Do the new cabinets have ports on the bottom? Any damping on the interior surfaces? Did you have access to a Shindo 604 to use as a guide?

Welcome to the Haven!
 
Sorry I can see this is gonna take me a bit to figure out,

Yes the cabinets have 4 rectangular ports on each one, I used some of the old altec graphs to calculate the proper port size which also looked very similar to some photos I found online. So far I haven’t used any damping in the inside, once the busy summer is over I plan on trying some and also some minimal cross bracing. I will report my findings. And the last one, No I don’t have access to one for a guide, I’ve heard a few but just photos for now.

As far as secret sauce I’m sorry I don’t have an answer I wish I did, maybe the 1/2 inch ply. I’m still astonished at how much like a drum they sound like if you rap or tap on them yet you don’t hear that when the music is playing. If anything I almost wish for a bit more bass sometimes but then it shows up and rattles your butt or messages you in the chest or gut. I was planning on building a few different versions and sizes but I am so pleased with these that I am just having fun enjoying the music. Also I’m sure as most of us know how much time, effort and man hours go into any decent build.
 
Back
Top