Hi from Bold Eagle

#1
I've been a long term member at the Vintage Asylum where I saw a link to this site. It looked interesting, so I joined.
I've been a long term audio buff. I'm 80 now and started with my first component system when I was 15 with a Grommes LJ (little jewel) three tube mono amp kit, a Heath two way speaker kit, and a VM changer.
I'm an engineer (retired) and I'm still somewhat active in playing with this stuff.
My current primary system is comprised of an Adcom GTP-400 tuner preamp, Adcom GFA-545 II power amp, a Rotel RCD-971 CD player, and a pair of custom made speaker cabinets that are fancier, mirror imaged, replicas of walnut veneer Original Advents using SEAS A26RE4 woofers adapted to the Advent bolt pattern, New Advent tweeters, and my own crossover design. My goal since the late 60's, has been to create a cost effective "Super Model 20". A reference to KLH's Model 20 Compact System which in 1967 was the best sound you could get for $400 and arguably marked the threshold of real high fidelity sound. Reading reviews on the Model 20 was an epiphany for me as an engineer. Putting a good system together is not primarily a component quality issue; it's a systems engineering problem. And so, 55 years later, I arrive at the system described above.

Jerry
 

opa1

Moderator
Staff member
#2
Welcome to the Haven @Bold Eagle! I've had the original Large Advent along with many others here. I'd like to see some pics of what you created. :)
Mark
 
#6
IMG_0820.JPG IMG_0816.JPG IMG_0815.JPG IMG_0814.JPG I just took a few pictures of mine that I will try to include. This being a first time here, I'm not sure if it will be successful. Anyhow, the cabinets are replicas of Original Advents. They are mirror imaged with one tweeter offset to the right, the other to the left. There is a front to back brace made from a 1.25" hardwood dowel. Cabinets are made from MDF, and veneered on both sides for stability. Grill surround is strips of curly maple. Veneer is matched on all four sides and both cabinets match. The tweeter is a New Advent tweeter which has the same bolt pattern as the original but lies flush with the baffle. So the grill panel was cut out to allow full dispersion. The woofer is a SEAS A26RE4. The adapter for it is made from an original Masonite ring Advent woofer with the legs cut off, and the Masonite drilled and notched to mount the SEAS flush. That allows the SEAS to mount to the standard Advent bolt pattern. The crossover is very simple, using an 8 ohm L-pad for the tweeter and a 10 uF Clarity PX film cap. The woofer rolls off smoothly; but has a 0.5 ohm resistor in series to control the Q to about 0.85 for a little more "punch" in the bass. The cabinet is about 60% filled with Acusta-Stuf. In the rear connector panel, there is a pair of 5 way binding posts on 3/4" centers to accept the dual banana plugs on my cables. The toggle switch hole is plugged. Sound is more open than an Original Advent, and imaging is noticeably better. If I succeed with the images, there is a long shot of my room, showing Sher Khan, my stuffed tiger mascot, sound absorber, and indoor photo subject. The room is basically 12' x 15' with double doors leading out into the hallway. The doors are in a 3' deep alcove in the center of the wall, so my listening position is about 1/3 of the way between the hallway wall and the speakers. There is no toe in or tilt, and the speakers are on 15" stands; putting the tweeters at ear level.
I tried SEAS 27TBFC/G tweeters; but they have very limited stroke and get edgy at moderate levels with my first order crossover. The New Advent tweeter has a larger radiating area, ferro-fluid, and a much longer stroke, and is considerably smoother than the original Kloss tweeter. The images from left to right are a long shot of the speakers; a shot of the veneer on the top of the left speaker; a close shot of the SEAS woofer and the adapter; and a full length shot of the left speaker with the tweeter offset to the right.
Jerry
 

TubeHiFiNut

Administrator
#7
View attachment 9092 View attachment 9091 View attachment 9093 View attachment 9094 I just took a few pictures of mine that I will try to include. This being a first time here, I'm not sure if it will be successful. Anyhow, the cabinets are replicas of Original Advents. They are mirror imaged with one tweeter offset to the right, the other to the left. There is a front to back brace made from a 1.25" hardwood dowel. Cabinets are made from MDF, and veneered on both sides for stability. Grill surround is strips of curly maple. Veneer is matched on all four sides and both cabinets match. The tweeter is a New Advent tweeter which has the same bolt pattern as the original but lies flush with the baffle. So the grill panel was cut out to allow full dispersion. The woofer is a SEAS A26RE4. The adapter for it is made from an original Masonite ring Advent woofer with the legs cut off, and the Masonite drilled and notched to mount the SEAS flush. That allows the SEAS to mount to the standard Advent bolt pattern. The crossover is very simple, using an 8 ohm L-pad for the tweeter and a 10 uF Clarity PX film cap. The woofer rolls off smoothly; but has a 0.5 ohm resistor in series to control the Q to about 0.85 for a little more "punch" in the bass. The cabinet is about 60% filled with Acusta-Stuf. In the rear connector panel, there is a pair of 5 way binding posts on 3/4" centers to accept the dual banana plugs on my cables. The toggle switch hole is plugged. Sound is more open than an Original Advent, and imaging is noticeably better. If I succeed with the images, there is a long shot of my room, showing Sher Khan, my stuffed tiger mascot, sound absorber, and indoor photo subject. The room is basically 12' x 15' with double doors leading out into the hallway. The doors are in a 3' deep alcove in the center of the wall, so my listening position is about 1/3 of the way between the hallway wall and the speakers. There is no toe in or tilt, and the speakers are on 15" stands; putting the tweeters at ear level.
I tried SEAS 27TBFC/G tweeters; but they have very limited stroke and get edgy at moderate levels with my first order crossover. The New Advent tweeter has a larger radiating area, ferro-fluid, and a much longer stroke, and is considerably smoother than the original Kloss tweeter. The images from left to right are a long shot of the speakers; a shot of the veneer on the top of the left speaker; a close shot of the SEAS woofer and the adapter; and a full length shot of the left speaker with the tweeter offset to the right.
Jerry
Very nicely done! :)
 
#9
A comment. Back when I was in college in Brunswick, NJ in the late 50's; there was a nice Hi-Fi shop called Hi-Fi Haven. I spent a lot of time (and money) there. Does anyone know the origin of this sites name?
 
#10
Here's a couple of shots of my adapter for putting a more conventional 10" into an Advent cabinet the Original Advent cabinet. It won't work on the New Advent cabinet as the woofer cutout is smaller. The woofer shown in the second shot is a Peerless that didn't work out; but does show the assembly. The inside diameter of the Masonite ring is almost large enough, and only needed to have notches cut for the cast legs on this woofer and or the SEAS A26RE4. The 25F-EW will also fit; but isn't good for an Acoustic Suspension design. Much better in an Aperiodic or Ported cabinet. In my L110 cabinets the 25F-EW is used in the unusual Port Assisted Acoustic Suspension alignment. Where the cabinet is filled with stuffing and the port length adjusted until the cabinet is tuned to the woofer's free air resonance 26Hz, and the desired Q obtained, in this case 0.9.
IMG_1577.JPG IMG_1578.JPG
 
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