Mini Advent 400 FM Receiver - Cute!! :)

[jdurbin1]

That 420S is cool! Reminds me a lot of the Quadraflex 085R I use on my repair bench (pictures borrowed from web):





I wonder if Quadraflex didn't copy the design a bit from Advent... would love to A/B the two for performance too, the 085R is surprisingly listenable for a little IC-powered amp.

John

 

[AdamAnt316]

That 420S is cool! Reminds me a lot of the Quadraflex 085R I use on my repair bench (pictures borrowed from web):

View attachment 1693478

View attachment 1693477

I wonder if Quadraflex didn't copy the design a bit from Advent... would love to A/B the two for performance too, the 085R is surprisingly listenable for a little IC-powered amp.

John

Interesting! Only obvious differences are the lack of a tape input (and the associated monitor loop), the addition of a headphone jack and a 12VDC input, and a small tuning meter instead of the directional LEDs. Also appears to have a metal back (and case?), while the 420S is entirely plastic. What are the overall dimensions? Also, is the tuning knob geared? Finally, what's the output wattage? I believe the 420S is rated for 5-10WPC or so.
-Adam

 

[safebet]

According to a post in this thread by one Fred Pinkerton, who worked for Advent in the late '70s, the 450S , along with the 410M (revamped 400) and 420S (stereo version of the 400/410M), were introduced after Henry Kloss left Advent, and not long before they went bankrupt and were bought up by Jensen. I suspect that the 450S was intended as a follow-up to the earlier 300 and 350 receivers. Alas, the 450S was apparently rather trouble-prone from the get-go, as noted in that post. A friend of mine has one, and it has various issues he hasn't yet been able to fix. My 420S worked fine when I last used it, except for dirty contacts in the (sealed?) input switch module.
-Adam

Just to note, I have two of the 450S receivers and really like them. One has a slight hum likely due to aged Electrolytic capacitors but fine otherwise. The matching speakers are another story, foam woofer surrounds have deteriorated and the resonant plastic housing gives little reason to resurrect them. Sounds really nice with a set of ADS 300's though.

 

[CT Jim]

Well, best laid plans for a Christmas present. The idiot who packed this mint 450S tight in a box with the speakers, wrapped the receiver in one layer of bubble wrap, and put the knobs to the outside. The weight of the shifting speakers when the box was dropped, cracked the face and bent the tuning assembly. It is now junk! Waiting for Ebay to refund!

 

[jdurbin1]

About 7-8 inches wide, maybe 6 tall and 5 deep. It's a plastic cabinet with steel back panel. Would be nice to have that extra input, for sure. I modified one of mine to convert the Tape Out to a Pre-Out so I could use it as a small preamp. Power is 8.5 WPC via a pair of Toshiba power IC's and it does have a vernier tuning mechanism.

John

Interesting! Only obvious differences are the lack of a tape input (and the associated monitor loop), the addition of a headphone jack and a 12VDC input, and a small tuning meter instead of the directional LEDs. Also appears to have a metal back (and case?), while the 420S is entirely plastic. What are the overall dimensions? Also, is the tuning knob geared? Finally, what's the output wattage? I believe the 420S is rated for 5-10WPC or so.
-Adam

 

[AdamAnt316]

Well, best laid plans for a Christmas present. The idiot who packed this mint 450S tight in a box with the speakers, wrapped the receiver in one layer of bubble wrap, and put the knobs to the outside. The weight of the shifting speakers when the box was dropped, cracked the face and bent the tuning assembly. It is now junk! Waiting for Ebay to refund!View attachment 1694566 View attachment 1694567 View attachment 1694568 View attachment 1694569

OUCH!!! The plastic on the front of these 'Response' receivers is definitely a bit brittle. When I got my 420S, it had a crack in the top of the front panel, above the tuning knob. Tried to glue it back together using model glue, and it mottled the paint a bit. Looks OK from a distance, fortunately.

About 7-8 inches wide, maybe 6 tall and 5 deep. It's a plastic cabinet with steel back panel. Would be nice to have that extra input, for sure. I modified one of mine to convert the Tape Out to a Pre-Out so I could use it as a small preamp. Power is 8.5 WPC via a pair of Toshiba power IC's and it does have a vernier tuning mechanism.

John

Very cool! The Advent 420S is about 6.5" tall, 5" wide, and 5.5" deep. Not too much bigger than the original mono Advent 400, which is a pretty good feat. Not sure who made the amplifier ICs, since they're buried inside the innards of the unit.
-Adam

 

[jdurbin1]

The Quadraflex uses the NEC UPC 1185H; I found out the hard way with a bench wiring error years ago, took out one of mine and had to repair it.

John