Stromberg Carlson ASR-444 - Studio 60 series. WOW

[Treyphan]

So I’ve read a bit about Stromberg Carlson in the past. Apparently they were a formidable force in the early HiFi days.(1930’s-early 60’s). Though I’d never stumbled across one of their units before.

Well I recently was GIVEN an ASR-444, along with a few other tube amps and about 1000 tubes. The tubes were quite a surprise. Lots of good audio stuff. Most still in boxes. The amps, besides the 444 were a Harmon Kardon HK-20 EL84 mono, which is gorgeous in its copper chassis and tube cage and also a SC Studio 6 7189 pre/amp combo that can be separated at the chassis.

The ASR-444 immediately caught my attention as it was running 4 7025a RCA output tubes. A “suped up” version of the 6L6GC. Which coincedently are the tubes my Mac MC240’s run. I’d hoped the quad was good and I’d be happy with that alone.

I must also mention none of the amps worked. Which is why they were free. So I went at the 444 first. Tested the 7027a’s which all tested great. Then the 12AX7’s and the 6AV6’s, the 6U8’s tested meh, as usual. Replaced those with some RCA blackplates I had on hand. I’ve got a TON of 6U8’s for my MX-110. Nice! I opened her up and inspected resistors, caps etc. nothing looked burned. So I gave all the controls, including the odd circuit breaker, a good Deoxit and cleaning as well as tube sockets and pins. Plugged her into my Variac, and brought her up slow. All the tubes glowed that glow we all love. Could it be? This thing works after sitting idle in a Midwest attic sense the “late 60’s”? Yup, it sure does. Hooked up some period correct Bozak B302a’s(restored Tobin mods) and my Tube DAC and a TD-121. Wow, this thing sounds delightful with all types of music.
I now plan to go through it and keep it. One of the BEST amps I have ever heard. EVER! A full restore will happen soon. As well as a custom cabinet.

For reference I run 2 MC240’s(completely restored with all NOS tele’s And RCA Blackplates) with a restored MX-110z, Thorens TD-124 MKII with SME and a Tube DAC. The Stromberg Carlson hangs with that system. No it doesn’t have quite the power of strapped 240’s, but it’s just wonderfully full, detailed, big soundstage and revealing. With all the tube yumminess too. The high end is glorious. Not etched or fatiguing at all, but cymbals sound so real. I can’t imagine how good this will sound once gone through.

Also got the HK20 to fire up after a quick cleaning. It sounds great too, would love another for a stereo setup if anyone has one? I may use with a third speaker from the center output of the MX-110. Just for kicks sometimes.

The other SC runs a quad of 7189’s, which I only have 2 of right now, someone poached the originals. I think I have a couple hid away somewhere. Won’t take 6BQ5/EL84, which I have a bunch of. So once I find a few more of those. I’ll get into it. It did have two perfect RCA 7199’s and 3 1960 Mullard mC6 Blackburn AX7’s and a 1960 Amperex Bugle Boy AU7. Which all measured super strong and I believe are original with the matching codes applicable to production time. Why someone left those babies is beyond me. The mC6 AX7 May be my favorite AX7, even over Tele’s!

Man, even in 2019 there are valve treasures to be found. Love being “that stereo guy”, people give stuff too! Usually lame 80s/90’s gear these days. But this I why I ALWAYS at least go look. Got my Sansui 1000a the same way, and a TD-124. I’ve told the owner I’ll throw them a bone if I make any $. Wouldn’t feel right otherwise. They didn’t realize what they gave away. Nor did they really care even once I told em. “NBd, you’re doing all the work, thanks”


I can now say, that imo, SC is a force. Get one if you see it! Anyone else currently running Stromberg Carlson tube gear and love it as much as me?My Fisher 500c May be on its way out, with what they get nowadays. This SC isn’t going anywhere.

 

[gadget73]

They did engineer their stuff well. Must have been paying the engineers with what they cut out of the design department though, cosmetically I've never found their stuff to be all that amazing. For a proper star ground system with sane operating points and good iron though, I'll take that trade. One thing I did find with my ASR-433, most of the resistors were way off value. Not sure if mine just got stored in an unhappy place or what but I eventually got tired of checking and just replaced all of them. More than half were out of tolerance and it was to the point that just shotgunning them took less time than individual testing.

 

[Treyphan]

Yeah, think I may go the “shotgun” route myself, on both the caps and resistors. Why chance it. I’d like this to be reliable as a daily driver for a second/third system.

While it’s certainly not a “pretty” piece of equipment. Mine isn’t too bad. Gold and white aren’t really my first choice. However they are in great shape and should clean up nicely. I do like how the 7027’s are horizontal. Kinda cool. Don’t see that much. The sound is just so sweet though.

 

[Tom Bavis]

Sams folders for the ASR-444 and ASR-660 are on my website: http://www.audiophool.com/MadeInRoch.html - and I have a scan of the HK20 too, email.

 

[rickl]

Tom, I really enjoy your Made in Rochester site. I've been there a million times. I really enjoy my asr-120 with matching tuner. Probably too nice for the garage stereo.

 

[Treyphan]

Wow Tom! That MadeinRochester site sure is really cool! Thanks so much for the heads up about it, and your work on it! You’ve got some really cool SC gear on there!

I really like the some of older SC amps you have on the site, got a great mid century Industrial look, I like and bet they sound killer. I’m assuming they are pretty rare, especially as some used Western Electric Transformers, from what I’ve read. Sadly we’re probably chopped for parts.

I’ve seen your name in most of the SC threads around the Internet. Seems your the Guy when it comes to SC.

I’d looked everywhere for a SC ASR-444 Manual, to no avail. Til you do kinfly pointed me to your site!
I’m about to sit and order the parts for a full resto, caps, resistors,etc...new rca’s, got some really nice WE NOS vintage wire I’m gonna use probably, some of the wire is pretty crusty. Probably fine. But why risk it imo? Plus I’ve been looking for an excuse to use it.lol

The RCA 7027a’s test like new, so I’ll use those. Got some old JAN NOS 6AV6’s I found in my stash, not sure what to do about the Phono....don’t really wanna “waste” good AX7’s on the so-so Phone section. Which as everyone before has stated; is the weak point. I mean it’s listenable, but nowhere near what I’m used to.
Thought about restoring it; but now I’m considering implementing a new one. Any rec’s? I’d rather not use a an external Ph Pre. I’ve got some, but I’m using a Denon DL-103r with the Table I’m gonna run with the 444. Which already utilizes a DIY SUT I made that I love. So if I could keep the “extras” to a minimum, that would be nice.

I’d assume parts will be here within a week, and I will take pics and post an overview of the Journey. Pretty excited, if it sounds this good now, man, gonna be a killer once at spec.

Also kinda cool they implemented a “Crossover” into the amp for Mono use, with a 3000 hz x-over point. Not that I’ll use it, cool none the less.


I am now on the hunt for some SC speakers. Not sure what’s out there, but a matching set would be nice.

Well thanks again!

 

[gadget73]

Could always rebuild the phono section. A lot of things used a single 12ax7 per side, so there are circuits to be had. Fisher, Harman-Kardon, or even the venerable RCA RIAA circuit from the handbook would do. I used an HK one in my 433, though i couldn't get it completely silent because of the AC heaters. I tore it apart too long ago to convert it to DC heat but never finished the job. Need to do that, the poor amp has been apart for a few years at this point.

 

[Treyphan]

@gadget73

Thanks for the feedback! My initial thought was the “RCA RIAA” Phono circuit. Think I’ll take that approach. Always wanted to check that circuit out anyway.

Listening to the 444 right now. Decided to throw a spare Quad of RCA 6L6 Black Plates In, while it sounded killer. I felt it was a “bit edgy”, if I’m being critical. Which isn’t uncommon, most love Blackplates, but it really depends on the amp. I think the guitar amp crowd, where they sound great has over hyped them. Went ahead and put some Phillips 6L6GC’s in, and that sounded really good. Gonna try a quad of GE’s in a bit here too. Why not? Lol I’ll probabaly stick with the RCA 7027a’s it came with though. They test basically new, and sound great.

I also want to get the Stereo 60 7189 amp goin. So I may get after that once the 444 is done. I have an empty console that it would fit great in. Problem is I need some 7189 tubes. I’ve only got 2, thought I had more. But haven’t located em yet. If anyone in AK land has some they’d like to trade. PM me, I have TONS of tubes and vintage parts. If not, I’ll order some of the Russian replacements. Too bad EL34’s won’t work. Got a decent amount of those.

Well, hopefully the mailman brings my ASR-444 parts soon. Really can’t wait, haven’t been this excited to work on an amp in awhile.

Well, til next time.....

 

[Treyphan]

Hello again fellow Stromberg Carlson fans!

Well, I’ve got to say. This ASR-444 is one of the best tube amps my ears have ever heard. Like I previously mentioned, I picked it up cheap and in rough shape. After a typical cleaning of all the pots/switches and all the inputs. I plugged her into my Variac, original tubes and all, and brought her up nice and slow. Everything went great, listened and was blown away. For an amp that hadn’t been used in 40 years to sound this good after a light DeOxit bath, well...I was surprised.

I’m normally a Mc Tube guy for my main systems, right now I run Mc240’s and an MX-110 all restored. So the ASR-444 had some stiff competition. But what I heard was enough for me to spend the time restoring it.

So that’s what I did, I was also just about to restore a Sherwood S8000 IV id ordered the parts for just before receiving this Stromberg.

Well, once both were done. It was no contest. While the Sherwood sounds really good. This Stromberg is way better, imo.

I replaced all the coupling caps on the 7027a’s with Jantzen Superior Z caps, really like those. Used Sprague Atoms for the 50uf’s, Jantzen film caps for the 4uf screen caps, replaced the can cap with a 30/30/30/30uf CE replacement. Just about every resistor was replaced with 1% metal films. The few that aren’t done yet are some that I’m waiting on. So many were out of spec I decided to just replace them all. Ordered the bigger wattage wire wounds too. I’ll post pics again when they get here, hopefully later today.

The Doubler caps were replaced with 220uf axial Nichicon caps, upping the capacitance from 100uf. I also replaced the top hat diodes with 1N5408’s, added a thermistor, kept the breaker, it works perfect and is in great shape. I’m gonna add a new 3 prong line cord with a receptacle still. I replaced the Aux rca jacks with high quality copper/gold plated rca jacks. ALL the remaining jacks will be changed. Just quite a tideous job on this guy. I also added nice 5 way binding posts to the original phenolic board. Only on the 8 ohm taps for now. Most the speakers I use will be 8 ohm atm.

I also replaced the 2 .10uf tubular Aqua Film caps on the Source switch with jantzen film.

Plan to do more on the control panel, just waiting on time and parts.

Overall I’m really happy with this Integrated. Right now it’s sitting in for the Main Mc System and I love it. No, it’s not better than a couple 240’s and a 110.....but it’s close. It’s also a much different sound. Maybe more “tube”, as Mc’s are so....well, Mc.

I love this amp. It’s never going anywhere. I have a few other things planned and may go through and replace all the wiring with better stuff. For now though, it’s a keeper!


@Tom Bavis , your site is quite the resource. I appreciate all your work! Keep it up!

 

[century tek]

I have a mono Wurlitzer organ amplifier that uses the 7027 tubes and I like it. I can also run the 6L6GC tube in it but here's some FYI for ya. Don't do the reverse. In other words, don't swap in a pair of 7027's into an amplifier that normally uses the 6L6GC. Off the top of my head, the 6L6GC has something like pins 1 & (?) tied together internally but the 7027 does not.

 

[Treyphan]

I have a mono Wurlitzer organ amplifier that uses the 7027 tubes and I like it. I can also run the 6L6GC tube in it but here's some FYI for ya. Don't do the reverse. In other words, don't swap in a pair of 7027's into an amplifier that normally uses the 6L6GC. Off the top of my head, its something like pins 1 & (?) are tied together internally with the 6L6 but not with the 7027.

You sir are correct! That extra “cooling” pin sure can throw a monkey wrench into everything. Unless however your 6L6 amp has sockets wired for both, like say the McIntosh MC240. However, if it’s not printed on the chassis, make sure and double check everyone.

This nice thing is, because I have a bunch of 6L6 amps, I’ve got like a dozen quads of 6L6GC tubes, and 3 7027a quads. That’s what tonight is for, gonna have a few beverages and see which tubes I like best. I’ll probably stick with the RCA 7027a’s it came with. But why not experiment. I will say RCA Black Plate 6LGC’s sounded great as well. That’s all I’ve tried though.

Running some Telefunken 6AV6’s, Telefunken and Sylvania 6U8’s(not sure which I like more surprisingly) and a couple Millard Blackburn’s for 61 in the AX7 spots.

Man I love tube amps and tube rolling! PS, Sylvania 6BL8’s sound great in here in the 6U8 spot as well. Found an NOS set in my Stash a bit ago.

Thanks for the tip though.

 

[Treyphan]

Ok, well. After a full night (13 hours of listening to the ASR-444), I’m more in love than ever!

I tried 5 different 7027a/6L6GC quads last night. Giving each plenty of time to warm-up and settle in. They were the following:

RCA 7027a’s that came with it - just perfect tubes for this amp. Really like everything.

RCA BlackPlate 6L6GC 1962 Date - The “Holy Grail” of 6L6GC tubes. It of course sounded tasty as all get out. Though, I really feel the Guitar crowd is what has pushed the price and lore of this tube. It is wonderful, but it’s certainly not my favorite of the 6L6 crowd. In any HiFi amp. Pretty linear, nice top end, lots of power. Just a bit “untube” like. Which some may like

GE “Grey Plate” 6L6GC -(1964 date) one of my faves, a little “slower” or maybe “Warmer” is a better word. Really liked them in here.
After the resistor replacement. The ASR-444 really sounds true. So the added warmth was nice.

Sylvania 6L6GC-STR - I LOVE THIS TUBE. In every amp. It’s what I run in both my MC240’s. Just a perfect 6L6 imo. While it may not be as fabled, I like it a lot. No different in the Stromberg. If I didn’t have the RCA 7027a’s. I’d use these.

Sovtek 6L6WGC - Mid 80’s tube which sounds great. I have a few quads of these I got NOS cheap about 15 years ago. Great tubes. NOTHING like the Modern Sovtek imo. Cool sound. I’d be happy with them if it’s all I had. However, there is better.

It was a lot of fun last night breaking this bad boy in and tube rolling. I really like the Tele’s in the 6AV6 and 6U8 spot. So I’m gonna stick with those. Tbh, changing these made very little difference.

I’m running a couple Siemens “Halske” mc6 12AX7’s for the Phono. While it’s not the last word in Phono preamps, as you can read in many other threads. It does sound pretty good.

My one complaint is a lack of volume on the Phono input. While I realize that Phono gain will always be less. It seems a bit extreme on this amp. Yes, I’m using the “Magnetic” input. It’s got a “crystal phono”, but I’m going to re-wire that as a second Magnetic Phono input.
Still need to replace the Resistors on the AX7’s. Maybe that’ll help. Really don’t wanna change the Sprague “Bumble Bees” they measure within spec.....Capacitance wise. ESR May be off. Those are pretty nice caps when working. Still may swap em out though, just too see. Can always put em back....

Anyway. The success of this amp, has made me decide I’m gonna do the same on the Stereo 6 Pre/Amp integrated Stromberg I have.

It’s pretty cool. It’s an integrated, but the chassis separates. 12 watts per channel of a couple 7198’s on each side.

I ordered a NOS quad of 6P14P-EV tubes. I o my have one set of 7198’s. Don’t wanna use em for testing. This one is Tube rectified via a 5AR4. I’ll probably do the “diode mod” often seen on ST-70’s to help the 5AR4 out. I’ve alwyas liked the sound on Dynacos after that mod.
Gonna try some vintage K-40y PIO caps for coupling on this one. Also this one has 4 can caps. My wallet doesn’t like that. Oh well, these amps are too well made and sound too good not too.

Anyway, I’m really glad I stumbled onto this ASR-444. Always read about Stromberg and their “Sleeper” status. Now I’ve heard it.

My Mc’s are jealous. Not an easy thing to do.


If anyone has any questions or recommendations lemme know.

I plan to finish installing the remaining RCA jacks and the IEC socket today. Then she should be good to go. Maybe new internal wiring at some point. However it sounds so good and no humming or noise. Why mess with it? Ya know...

 

[Tom Bavis]

I've seen very few bumblebee caps without significant DC leakage... change 'em!.

 

[gadget73]

^^ this

If this has PEC units for the phono stage, try to measure them as best you can. Mine were bad.

 

[Treyphan]

[

I've seen very few bumblebee caps without significant DC leakage... change 'em!.

@Tom Bavis .....Yeah, that’s kinda what I thought. Figured it was “wishful thinking” that those Bumble Bee’s would be able to stay. I’ve got caps here and ready to go. I’ll install them. Not going to question the “Stromberg Carlson Swami” Lol
Thx again for all your work on that website. Incredible resource. I plan to take a very high quality photo of the schematic on the bottom plate of my 444. If you’d like it for your website. Let me know. I know Stromberg had various versions of their Amps. Maybe it will help someone.

^^ this

If this has PEC units for the phono stage, try to measure them as best you can. Mine were bad.

Ya know @gadget73, I wondered about those PEC’s. Because, yes the 444 has ‘em. Need to ID the values/circuit. Perhaps I’ll make some small replacements on a breadboard. Just hope they will fit. At this point though, with how good this guy sounds. I have no issue replacing them if it’s helps the Phono.

I know a lot of people don’t like the SC Phono stages. This one sounds good though for an integrated. Plenty good to use.

Yeah, The MX-110 Ph stage beats it, no surprise, I also use an EAR 834P PH Pre with my TD-124 which also beats it....again, no surprise. Those are top end Ph pre’s though.

I have a few other external stages like the Pro-Ject one, for example. The SC hangs just fine with those. No it isn’t AS “refined”. Yet still makes vinyl sound great and detailed. Most would be completely satisfied, or it would out perform their ‘Table/Cart.

However something is up with the gain on this I believe. It’s just too low. Tried a dozen different NOS 12AX7’s.
So it’s not that.Hopefully the PEC’s fix it. Too bad no one makes replacements, just for aesthetic purposes.



As my Fiancée said “Wow, that little guy really packs a punch”. I think that sums the ASR-444 up. It’s hooked to a set of Bozak B302a’s with Tobin Modded Crossovers I made using very high end parts and wire. Just a perfect match for the 444, at about 96-97 DB/watt.....those 30 Stromberg Watts make them SING. Plenty of deep bass as well. I’ll measure later and post the graphs. Just balanced sound from top to bottom. Honestly I’m floored.

Also Managed to get the Stereo 6 apart on the bench. Can’t wait to hear it once restored. I’m hooked. Stromberg is my new addiction. Lol

 

[Treyphan]

^^ this

If this has PEC units for the phono stage, try to measure them as best you can. Mine were bad.

@gadget73 I also meant to ask...

What were your thoughts once you changed the PEC’s? Did it help the Phono gain? Overall sound?
Did you use NOS PEC’s or make an equivalent? Any and all advice on this part is gladly accepted and appreciated.

Thanks again!

 

[gadget73]

It still didn't sound good. I ended up ripping the phono stage out entirely and rebuilt it with a different circuit. I built one basically "dead bug" style, it was a ball of components all soldered together in a mess. I have built new PECs on perf board for other things.

 

[Treyphan]

Back with another ASR-444 update. Well, this amp just keep getting tastier and tastier! Not sure if it’s the caps “breaking” in, if you believe in that, or if it’s just me settling into the sound. TBH, I don’t really care.
This 444 is now my favorite amp I own, out of about 50, SS and Valve. SET or PP.....I love it.

I replaced the 2 27ohm 2 watt Resistors back by the output tubes. The tiny bit of hum I could hear with the gain maxed out, is gone now. Dead silent. I mean I had to stick my head a foot from the speaker to hear it before, but nothing now.


I hooked the MX-110z up to it and MAN....that’s a cool sound. Love this guy and will buy every SC I ever see the rest of my life.

I’d like to get a “beater” 444 and use the guts to make just an AMP, ditch the pre. Not that the pre is bad, just wouldn’t mind a straight up 444 amp section. Nice iron.

Also ended up swapping the 6U8 Teles for the 6BL8 Sylvanias, just sounds cleaner. Love
Me some Telefunken, yet still went Sylvania. That’s cool, Tele 6U8’s are my 110’s preferred diet, I’ll save em for it.

Good stuff.


Anyone here ever work on the Stereo 6 SC? Quite interested, love that it comes apart. Depending how it sounds maybe I’ll use the amp section with the 444 in a Bi-Amp setup with my Bozak Symphonies. Decisions decisions!

 

[Treyphan]

Back with another update...

So I went ahead and re-capped and replaced all the Resistors on the 12AX7’s for the Phono. I used the OD’s and managed to shoehorn the 600v version in there, also some IC yellow films as well, used 1% Metal Films for Resistors.(they’re are a few metal oxides where I ran out of films. I’ll replace when I replenish)
I also replaced almost all the remaining few Resistors on the 6AV6 and 6U8 spots. Somehow I missed a few on my order. So I have 4 left to do. A couple 560 ohms and a couple 1.5k ohm....which I thought I had.

Either way I ordered them and the 2 220 ohm 7 watt Resistors at the back end.

Then pretty much everything under the chassis will be new. Minus wiring. Oh and the rest of the RCa jacks I need to replace. Not looking forward to that. Kinda a pita. Oh well.

I’ve replaced a few small coupling caps on the tone controls and a few Resistors. Though I intend to replace all and rebuild the PEC’s. Someone really needs to start making a selling those. They could get rich! Hmmmm....lol

ill post pics when done. Doing that portion 1 step at a time. Listening in between. It’s tight and hard to see if I break a lead or crack a solder joint. This makes it easier to pin point any issues.


I will say the Phono does sound a lot better, still not what I’d hoped volume wise.
Still gonna work on that a bit. Might just leave well enough alone and use an external PH pre.

Tbh, I’ve been swapping between the Integrated pre and using my MX-110z with the 444. I really like that sound, and it eliminates the need for a Ph. The 110 has the best Phono Pre I’ve ever heard in a non stand alone unit.

This has been a really fun and rewarding project.

Even found an NOS “backup” set of 7027a’s, was able to trade a buddy some other stuff! Score!

Here’s another pic with the Phono stuff done.





EDIT: ok, so I tried a much higher output Cartridge, my Ortofon SPU G/Te @ 7mv, compared to the other MM carts I’d used. It obviously helped the volume.
Been using a Grado 8MZ and a Shure V15 III which are in the 4-5mv output. Which is “right around normal”. Those are just too quiet. Sound great, just quiet.

I realize Carts of that time were higher output voltage, but 7mv? Idk. Did they really design it for that much?
The Phono sounds good, much better than what the ASR-333 reviews say. I need to compare the schem’s, see if they are in-fact different. They must be. I’m not that deaf. I know a good Phono Pre when I hear it usually. Maybe I need to clean my ears. Lol

Also, I hooked up a Denon DL-103r with a DIY SUT using Altec Transformers, it also sounded great. Volume was “less” of an issue.

Kinda confused. Am I missing something? Not as far as SQ, I’m good with what the PH puts out, just need more volume. Is there a possible resistor value that can be changed.

I need to really dive into this, but I have a slew of stuff that needs my bench/attention and I’ve already spent ALOT of time on this ASR-444. If I can’t correct the volume issue soon. I’ll just use a External Pre like I said earlier.


But I’d like to get this, after about 25 hours of “break-in” on the AX7 caps, it sounds stellar. Just TOO QUIET! Lol

Might be a loosing battle. This is the “little amp that could”. Haha Sp I’d like to get it the whole way. Otherwise. The ASR-444 is a fine amp.

Be nice if SC had paid more attention to the Wiring. Yikes, atleast they didn’t chassis ground. Still, routing leaves a lot to be desired. I have no him or buzz and black background...but, could it be better?

My anal self says yes. Haha

 

[Treyphan]

Ok, back with another update. Might be talking to myself at this point, however, perhaps this thread will help someone down the line......

Ok, so after replacing all the passive components “under the hood”, I moved onto the Tone Controls. Man, it’s even tighter in there than under.

I’ve got probably half the Resistors replaced, and 8 or so of the maybe 15 caps done. I gave up on measuring, so many were out of spec, like others have said.I just “shotgunned” it. I’ve managed to save and document every part except 1 100k resistor. Incase someone ever wants to use out of spec “original parts”. Lol I mean, idk, just saved em. I’m anal.

Anyway, replacing the Caps on the Bass controls really helped a lot. Was kinda surprised. Also added some real nice AudioCap theta’s I found laying around to the Input Selector. What an improvement.

I know not everyone buys into the “caps changing the sound” theory, not sure I do, except I heard it with my own ears. Many times. I wouldnt have purchased those caps for that position, but I had em and Ive gone all out on this Amp. So why not. Can’t hurt.

I’m a bit concerned about the PEC’s, but they are only used when the “Subsonic filter” is on(bass pots pulled out) on the 444. Which I don’t use, it works tho. My tables/system are fine without it. I do have a 6 axis isolation table though. So my 124 runs pretty smooth.

I also added some K42y .10uf caps as By-Pass caps to the 220uf PSU caps. Why not? I had em.

Also, after all this work, replacing everything, the Phono Section sounds great! Couldn’t believe it it’s a very nice PH Pre. Not gonna win any contests, but it’s very competent and true.

The volume is perfect now! Finally! I really wanted to make sure this thing worked all the way around. I’ve been swapping back and forth between using my MX-110 as a Pre, and the 444 itself. While the 110 ads the Mc Magic. I’d be happy with the ASR-444 on its own.



Well, now that this is done. Time to finally live into the Stereo 6! I’m thinking I may Speedtest the chassis, and use the Amp as a second amp in a Bi-Amped SC system. Using an active crossover. The Stereo 6 feeding the top end, and the 444 doing the bottom end. While the 444 still has its tube goodness, it’s a completely different amp now. I feel the modern components really let this circuit design shine.its tight, fast, articulate and still smooth/warm enough to allow hours in end of listening without fatigue.

Would love to find another set of 444 transformers and build a stand alone amp. I think it would hold up with the like of a Citation V/MC240 with proper wire routing and no pre stuff. Really excited. It’s still my main amp. Which if have never guessed.
This may be the most rewarding build/restore I’ve done to date. Not that I’m some Swami of HiFi, but I’ve restored a number of amps, SS and Valve. SC is the real deal.

Now I just need to find some of those Mono 6L6 SC amps I see floating around the bay.