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Bogen DB-130 Mono Amp; What to Do? Help, Please

I have a mono system myself (which is what got this whole thing started), with

  • Rek-O-Kut N33H with Empire 980 arm and Denon DL-102 "compliant mono" cartridge
  • PhonoDude phono preamp
  • 417A/300B version of TubeLab's Simple 45 amp (CCS on top of 417A) with regulated power from Heathkit IP-32.

I am building a Salas SSHV2 shunt supply for the preamp; not sure any vintage preamp (let alone the DB-130) will be in the same league.

My shop system uses a TubeLab Simple SE modified to also accept 6AV5GAs (w/ outboard sockets); I am running those at ~23 watts dissipation (~330Vp, 70ma), effective double the book value. We'll see how much abuse those little sweep tubes can actually take. Alternately, a recently recapped Quad 303 (for British music, particularly Keef & Mick).

Not sure where the the DB-130 would fit into this scheme. Maybe in lieu of the Quad 303, but I don't need the preamp section in the shop...


In france, there were La Maison de L'audiophile which had the great Mr. Hiraga who made demos in an old cinema with this kind of equipment in 1980s.
Most of the listeners were stunned, how such ancient audio systems can reproduce sound in such a special way.


So there are two things for any serious listener before writing or contributing any substantial posts about those amps and systems and not speculate about their qualities:
-to hear such a full Western Electric System
-to understand what makes it so different compared with todays audio electronics.



I don't think that here are so many of us who have done both.
Much of the writing about it is speculation and justifying witout basic knowledge and own experiences. So this is the usual "talk is cheap" in an audio forum. Talking about something one never knows and one hasn't made own experiences with.


Of course, technically those systems are imperfect, compared to modern ones.
But if thats the only thing what counts in audio, why not use an all so modern digital equipment and the most modern SS amp instead of tubes?
Technically, those are much more perfect.
But we all know that this isn't what counts in the end.


I don't think that this argument is a satisfying one, but it will give peace of mind.
 
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I have a mono system myself (which is what got this whole thing started), with

  • Rek-O-Kut N33H with Empire 980 arm and Denon DL-102 "compliant mono" cartridge
  • PhonoDude phono preamp
  • 417A/300B version of TubeLab's Simple 45 amp (CCS on top of 417A) with regulated power from Heathkit IP-32.

I am building a Salas SSHV2 shunt supply for the preamp; not sure any vintage preamp (let alone the DB-130) will be in the same league.

My shop system uses a TubeLab Simple SE modified to also accept 6AV5GAs (w/ outboard sockets); I am running those at ~23 watts dissipation (~330Vp, 70ma), effective double the book value. We'll see how much abuse those little sweep tubes can actually take. Alternately, a recently recapped Quad 303 (for British music, particularly Keef & Mick).

Not sure where the the DB-130 would fit into this scheme. Maybe in lieu of the Quad 303, but I don't need the preamp section in the shop...
With shop music its a different thing.
 
>Not sure where the the DB-130 would fit into this scheme.

With a spare OPT, into the wide eyes of some "fleabay" purchaser looking to get into tube audio!

With the spare cash, into the fund that supports all the other stuff's maintenance and upgrade needs.

Reading your replies makes me sorta wish I'd kept some of the stuff that had passed through my fingers over the years...
 
>
Reading your replies makes me sorta wish I'd kept some of the stuff that had passed through my fingers over the years...

Believe me, this was all a series of accidents. I've had my share of stuff slip thu my fingers:


I had a rust-free XKE coupe, a series of Alfa Romeos, a Lotus Europa...
My mum was moving out of her summer cottage in Blowing Rock and offered a massive collection of Fiesta Ware (the brightly colored dinnerware certain colors of which were radioactive).

How Radioactive Is Fiesta Ware?.

and now goes for massive bucks.

But you are correct; I got lucky taking-off this past decade from audio. Just today, I gathered-up four Thorens turntables that I forgot I had (they WERE cheap a decade ago), all working. Checked prices on FleaBay- WHAT?!?!the heck?

I've uncovered enough stuff that I can make the Chief COok & Bottle-Washer ecstatic by getting rid of half of it, and still be considered a hoarder in need of intervention...

BTW my son-in-law is a Houston Fireman (quit PhD program in History when they restarted HFD Academy classes again a few years ago(!)). He says "hoarder fires" are the worst: (a) piles of flaming stuff ready to avalanche down on you, plus (b) the inevitable bodies (human and animal) buried under mounds of charred debris. Grisly stuff.
 
With shop music its a different thing.

Amen. I use Spotify Premium ($15/month for a "couples" account; 2 people same address, high quality streaming and no conflict) and a nice inexpensive DAC (iFi Zen). It runs 12 hours a day.

Dunno how they can make any money off of retired folks. Or folks that work from home nowadays for that matter.

I will say that the little Simple SE with red-hot 6AV5s works pretty good to fill the volume. Crank up ZZ Top "La Grange" (just down the road from here, ya know; they had a lotta nice girls out there), and the neighbors start with the funny looks.
 
I don't think that here are so many of us who have done both...

So WHEN did WE/RCA finally pull the plug on their leased theatre systems?

[I've been in Texas so long, I whispered THIE-AY-ter to myself as I was typing]

Mum used to drop-off me and my brother at the movie theatre some Saturdays when I was 8-9-10 and my brother 2 years younger. Parents did stuff like that then...that would have been 1961-1963. I'm pretty sure I was listening to 300Bs...

And right this second I have Heifetz & the Chicago Symphony playing "Tschaikowsky" via an RCA Shaded Dog (LM-2129) thru a 300B...
 
He says "hoarder fires" are the worst: (a) piles of flaming stuff ready to avalanche down on you, plus (b) the inevitable bodies (human and animal) buried under mounds of charred debris. Grisly stuff.

The Fire Academy trainees in Florida are told to get the people out first. Then ask questions of the most coherent survivor. The number one question is "do you have any guns, and if so how much ammo do you have, what kind and where in the house is it.

Some of this was a result of a house fire back in the 70's where a fireman was killed by an exploding gun safe.

BTW, I helped a hoarder push an early 70's Europa into his barn back in the 80's. I later traded him an old car for a nice tube stereo from that barn and I could see evidence that the Europa was still there underneath a large pile of junk. My guess is that it's still there along with several other formerly nice cars.
 
So WHEN did WE/RCA finally pull the plug on their leased theatre systems?

[I've been in Texas so long, I whispered THIE-AY-ter to myself as I was typing]

Mum used to drop-off me and my brother at the movie theatre some Saturdays when I was 8-9-10 and my brother 2 years younger. Parents did stuff like that then...that would have been 1961-1963. I'm pretty sure I was listening to 300Bs...

And right this second I have Heifetz & the Chicago Symphony playing "Tschaikowsky" via an RCA Shaded Dog (LM-2129) thru a 300B...
Something in the 1950s they were pushed out of business.
Nice record, btw. You are safed.
 

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Of course, it is. Everyone who has compared stereo and mono played on a real mono system can confess that. Stereo is mostly a gimmick and was introduced to sell the same records twice- one in stereo, one in mono.

The Beatles were only keen to get the mono mixes right- stereo mixes were ping pong stereo and they did not mind at all.
Everytime I have to choose- I'll choose the mono version. And mostly its much cheaper, too.
What a wonderfull world!


Btw, maybe you've heard it in cinemas: Western Electric 43A. [FONT=Arial, Helvetica, sans-serif]Wonderful amp , dry sound , frequency response is extended.The most correct amp I ever listened. Better than any 300b amp I owned.[/FONT]

[FONT=Arial, Helvetica, sans-serif]Output tubes are WE 242c : the sound is completely different in respect of Rca 211a. [/FONT][FONT=Arial, Helvetica, sans-serif]WE 242c is dry and clean.[/FONT]
 
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But then again, I'm the type of person that keeps racks of old tube stuff IN MY OFFICE.

As am I. HOWEVER, the Chief Cook & Bottle Washer (CC&BW) is a self-described minimalist (read: sadist).

Her latest (internet-inspired) jag is to throw away 400-something items in February. It's an additive integer sequence (1 item first day, 2 the second, etc).
I have no idea how these people live with themselves.

In addition to the brownie points for adding to the Disposal List, I also get points for selling stuff on eBay (which, in fairness, she administers, including the shipping druggery).

Consequently, my stash has of necessity been DISTILLED down to near-term "justifiable" items. Fortunately, I have also become expert at obfuscation, disguise and concealment, e.g. "I didn't know we had those..where were they hiding?"
 
Fired-Up(!)

The cheap 6CG7s arrived from FleaBay.
I scrounged up the rest of the tubes and warmed it up gradually on the VARIAC.
Used a Y adapter from the Spotify DAC.
Figured “Songs for Swingin’ Lovers” would be period-correct, so as to not shock the components.

First, one of the rectifiers (one of only two 5Y3s I have; must have come out of this amp) started a fireworks display. SHUT-DOWN! Crash the Control Rods!
Turns out the box had “one bad diode” written on it. You know you’re a scrounge when you keep a bad 5Y3.

Back to the rectifier box: AHA, Chinese 5Z4P with their pert little bottles. Close enuf. See photos below.

Took a minute to find a good input (tape monitor, it so happens) but then BOOM, there’s Frank crooning at his peak.

Wow. Volume & tone work good, but most of the inputs are dead or near-dead.
So the power end is near-perfect (BEFORE bias check or adjustment) but the front-end needs some tracing work...

Bogen’s component quality must have been pretty good, if those power supply caps reformed (at least partially) after all these years. The caps on my Quad 303 were in the picofarad region; completely SHOT.

Also, the Bogen is super quiet between tracks, which is amazing, as I have Frank cranked up pretty good. The shop is 750 ft2 with a cathedral ceiling covered in Homosote board, and the Bogen fills all of it....

More later. Looks like I’ll be putting on the Fleabay at “Asian Audiophile” price. If it sells, fine. Otherwise this thing deserves a little work under the chassis.
 

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