AMPEX 354 and 440 recording electronics & MX10/35 AM10

I thought it might be worth it to post this here since alot of Ampex recording electronics are bought/sold on eBone and other spots to be used a pre-amps and di's and such. The Ampex 354, PR10, and 440 (all series) channels DO NOT have mic pre circuitry in them. You can't buy a 354 and turn it into a stereo version of the 350 or the more popular 351. All of these recording channels have octal socket plug in units that require either balanced line matching/bridging xt's or mic pres. The 354 and PR10 machines took the same plug ins as the MR70, little cans not dissimilar in size as the optics plug in on the LA2A; there were two, a 40db and a 60db, the 40 had one NuVistor and a Beyerdynamics peanut XT, the 60db had 2 NuVistors and a Beyerdynamic peanut XT. The 440's and all subsequent machines that had octal sockets, the MM1000 being the last I believe, had a solid state mic pre plug in. None of these pre's work at all with present day close mic'ing, the XT is smaller than the first phalange of your index finger; they work fine as room mic pre's. Anyway, if you see one of these on eBone don't believe the seller's claims that you can make Phat Evil mic-pre's out of them, YA CAN'T! So it would be a perfect waste of the $300-500 USDollars these things are presently going for if that's what you're wanting to do. And the PR10 stereo electronics melt down from overheating issues, have a voltage regulating tube in a poorly designed power supply and can start oscillating like crazy unless you can design a zoebel on the outs. Same for the 10 series tube'd monitor amps. The 440 series Reproduce card has a nice line amp on it ut also has impedance issues that need to be addressed and the dreaded Beyer xt's. And don't forget, if you've got 350's or 351's the hi pin is 3, not 2.

The MX35 and MX10 mixers have the same Beyer XT's and they output from a cathode follower at 100Kohm. Yes, that's right, 100K ohm. The outs were intended to go directly to tape heads. So if you snag one of these for the $1400 they seem to be routinely going for these days don't neglect to buy an output transformer to get the signal down to line level.

And for the record, the AM-10 is a pretty crappy early solid state mixer that's noisy and distorted w/the same microscopic XTs that saturate when somebody drops a cymbal. The guys who were around when these things were designed confess they're pieces of crap and have no idea why they went out the front door at Ampex in the first place when they should've gone right into the dumpster instead. And routinely laugh their asses off when one sells for more than $20.

And yes I do have a motive for posting this here other than looking out for everybody, this is far less generous than all that, I'm trying to score a 354 controller for an orphaned transport I have. I would get the 351's but Steve Albini's seen to it that those will never any longer be available for the price he original got his for--FREE FROM THE GARBAGE IN AN ALLEY BEHIND A RADIO STATION SOMETIME IN 1981. Thanks a whole lot Steve, btw; someday I hope you'll figure out exactly what "secret weapon" means.

All righty then! Roger that, over-n-out!

P.S.: the 620 montiors make crappy electric guitar amps, even for practice. Nice acoustic guitar amps, but crappy electric guitar amps. Same for 2010 & 2012 which are exactly the same monitor. The driver is really close to a Jensen L8 but not quite, and it's a "purpose designed" thing, the amp is sort of crappy w/any other driver in any other cabinet. Even the home consoles w/the 6V6 amps (same amp. btw) use these drivers. The 620's went with the 600 series recorders, in suitcases and "portable" as such, back when they called roadies sherpas.

10-4!

Brad,

Word.

The 351 circuit on Albini's forum can be PTP'ed to create the mic pre section as he's omitted the transport circuitry. Anyone can do it, one doesn't need to go hacking up perfectly good (and increasingly more expensive) original Ampex pres. I am planning to breadboard this circuit soon, so I'll see how it goes. Should have lots o' gain with the original 1:15 IP, so I plan to use mic selection (mainly ribbons) and placement to attenuate.

I do have 4 original 351 electronics I am in the process of restoring. Two are from 1960-ish (grey chassis) and the other two are from 1963-ish (goldish-plated chassis). They are more or less complete, but in various states of disrepair (all but one is missing the input transformer). I plan on using these for their designed intention, an Ampex 350/351/354 stereo transport I am currently in the market for. All four of my pres are masters, so I'll need to convert at least one of them to a slave. I also have a butchered 351 electronics I have no idea what to do with. I will probably use the (fortunately unhacked) front SS panel of this for my Albini 351 mic pre mod.

Thank God I picked these up before the Albini craze! :shock:

outside of steve albini, can someone who is using 351's as mic pres please step forward and extoll their greatness?

crickets? anyone?

they dont sound bad, but jesus, for the work you have to do to these things you could buy the rca kit from k and k and totally slay. The 350/351 is really the worst case of hype out there. I have a 351 left, I keep it secretly unplugged...

dave

There's a transport on eBone in a 300 portable case in Montreal but that's a fuk-all long way a away from Hawaii. If I hear of anything in SF/Left Coast I'll ping you. Too bad you can't take a Grayhound from here to Honolulu, that's really the cheapest way to schlepp these things around.

Alright, if you like I'm sending you digi-pics of my electronics, nobody believes it when they see it, BUT they were modded at Capitol, pro'ly in LA. They absolutely knocked the wind out of some of the stock monsters on the Ampex list. I'm keeping them this way but freshening them up and modding the meter rectifiers ala Elliot Sound vu/ppm meters. And of course, since you can't buy a broken RatShack portable cassette player in this town w/out some sort of Grateful Dead pedigree, they guy I bought it from (now a realtor) just *had* to give me a copy of his G.D. public radio interview "montage" on cd, an hour long incomprehensible broadcast piece that's about as good as mystery meat paste in a tube. Really, you can't pick up a half used bar of soap w/out somebody somewhere saying "Jerry!"

Actually, I'll say that I love them. I've used Steve's on a few sessions. His sound great. Sound awesome actually. But yeah the hype is retarded. I think the Universal 610 is more fun. I'd like to hear what K&K's RCA's are all about.

I had an MX-10. The unit's output was never a problem for me. Sounded great. But the input was the real problem. Those little Beyer's would saturate if you looked at them too hard.

I want a 354 machine. Why? I like tubes and I like tape.

[quote author="soundguy"]outside of steve albini, can someone who is using 351's as mic pres please step forward and extoll their greatness?

dave[/quote]

I love Big Black, I loved 'em them and I love 'em now, "Racer X" still kicks my ass, I love the Pixies first record, then and now, I lived in CHi for 15 years and I know where Steve's stuff is coming from, musically, esthetically, work ethically and philosophically, it's not different from stuff you absolutely know is from NYC. But Steve does have this icky habit of which you speak; and then every wanna-be wirehead in the world is gobbling these things for $1200 a pair, & he found his in a dumpster. It's kinda transparent.

And the time it takes to make them makes a lot of sense when they're your best bet on pre's because you're a broke 22 year old musician living in a gigantic dirty room w/8 other people in a nasty neighborhood tryin' to knock it out and generate some cash and enough noteriety to do what you want to do for a living all day everyday. I recall the term "street cred" being bandied about among the kids in the neighborhood (see "Hi Fidelity for realistic visual references to the neighborhood.)

They're okay like you say but they're even better when they're pushing a transport around. New heads from John French, not even the mastering heads he's got for $600 per, and you've got some lovely signal preserved for all posterity. Warm punchy signal too! (duck! incoming!)

ho ho ho, as a tape machine they are one thing (think LA woman sound) but as a mic pre, quite completely something else...

dave

Brad,

Because there ain't anything here in La-la land Ampex wise, I have already accepted the fact that I will have to freight something in from the 48. I can also have something sent to my sister-in-law in Seattle and when I go up to visit her, I can ship it FedEx for cheap as I'm an airline employee...

Miko,

The 354 transport is pretty much the same as the 351. Maybe some super minor differences, but I think they pretty much interchange. You wanna stay away from the 354 electronics, though... I think you'd be better off with 351 pres for the transport...

[quote author="fazeka"]Miko,

The 354 transport is pretty much the same as the 351. Maybe some super minor differences, but I think they pretty much interchange. You wanna stay away from the 354 electronics, though... I think you'd be better off with 351 pres for the transport...[/quote]

Plug-n-play. I think the 354 transport control issues mentioned on the list by George S. come from the fact that he's a picky-pro and he didn't have many alternatives when he was punching a time clock. The coolest thing to do is get a late model 300 or 3200 transport (I know where there's a bunch in a storage locker in LA, shhhhh!) that have the all metal decks and the motors for 14" reels, trash the control box and rewire for 350 controls. I've got a scat and a phone number. You need new heads tho, either the 300 or the 3200 have the correct head nest. John F gave me a price of $1600 for 1/2" heads + $300 to mod the headnest and you can run half inch with the stock idler, 1/4" a little more than half that heads mounted and aligned. ElectroSound pinch roller for 1/2" or 1" (although the 1/4" is *really* close,) have a machinist turn a new idler for the capstan for 15/30 ips and you're in.

Old 300's have wood decks tho, bad. And you have to check out that tire on the capstan motor that spins the capstan, it has to be close to perfect, no flat spots.

[quote author="fazeka"]Brad,

Word.

The 351 circuit on Albini's forum can be PTP'ed to create the mic pre section as he's omitted the transport circuitry. Anyone can do it, one doesn't need to go hacking up perfectly good (and increasingly more expensive) original Ampex pres. [/quote]

'specially since you can get both the i/o xt's from Sowter.

Wow, I just had a folk-all incredible idea, I could engrave stainless 351 electronics face plates and jamb them w/fazeka's roll-your-own pre. Then anyone could command the cache of having an AMPEX! in their rack, maybe two, since they're so compact, and you could actually have something like 16 in/out living behind them. WE'LL BE FILTHY RICH!!!! And we could get Steve to schlepp 'em for us! Cool, now I'll be able to buy that house nextdoor to David Geffen! Alright!

Does anyone know what the difference is between the 350 and the 351? My studio partner just picked up the record electronics of a 350 for use as a mic pre. Anything I need to do to this to make it work as a mic pre?

350 is older of the two, PS not built in, PTP, older octal tubes, supposedly more headroom.
351 is newer of the two, 3 PCBs w/Amphenol (?) edge connectors, 9-pin miniatures (i.e. 12AX/U/T7s), PS built in.

[quote author="tubejay"]Does anyone know what the difference is between the 350 and the 351? My studio partner just picked up the record electronics of a 350 for use as a mic pre. Anything I need to do to this to make it work as a mic pre?[/quote]

Did he get the power supply too? 351's have a psu in each one of the electronics, 350's have a stand alone psu. They're wired for DC filaments.

http://www.ampexdata.com/Support/Legacy_Manuals/legacy_manuals.html

Check which pin is hi, it might still be 3. Albini's forum notes wouldn't be too far off the mark in spirit but of course not in detail.

350's have that ever-loved HA-100X in them too.

[quote author="bradzatitagain"]
'specially since you can get both the i/o xt's from Sowter.[/quote]

Brad, I was the one who sent in a sample to Brian to get those cloned. I got the first two he did, AFAIK. I am still looking for two or three originals as Brian can't do the octal base as per the originals. But I will use the Sowters for my 351 clone. :thumb:

[quote author="MikoKensington"]350's have that ever-loved HA-100X in them too.[/quote]

Sometimes, I've seen three different xt's in that spot, mine have an in house Ampex GTC.

[quote author="fazeka"][quote author="bradzatitagain"]
'specially since you can get both the i/o xt's from Sowter.[/quote]

Brad, I was the one who sent in a sample to Brian to get those cloned. I got the first two he did, AFAIK. I am still looking for two or three originals as Brian can't do the octal base as per the originals. But I will use the Sowters for my 351 clone. :thumb:[/quote]

Did you have two 3&3/4-7&1/2ips and two 7&1/2-15ips but not a matched master slave of one or the other?

Right, I just rolled back to that other thread, dats you!

I don't think changing the eq circuit's going to devalue anything to get a matching channel for your good one; you don't have matching numbers, so to speak, so you could resell it as a working deck sometime but not as a deck that was originally sold together. I also don't think throwing the Sowter input in there until you find an octal transformer would be a bad idea. Some of them have A-11's which is the same xt. It's that funky output that you can't replace with just any old thing. I bet you could put one good one together with all the spares you have, change the eq circuit, procedure's in the manual, keep one for spare parts and sell the other two on the eBone and finance the second half of the project.

[quote author="bradzatitagain"]Some of them have A-11's which is the same xt.
[/quote]

You mean some 351s came with A-11s? :shock:

[quote author="bradzatitagain"]It's that funky output that you can't replace with just any old thing.
[/quote]

Not even the Sowter?

[quote author="bradzatitagain"]
I bet you could put one good one together with all the spares you have, change the eq circuit, procedure's in the manual, keep one for spare parts and sell the other two on the eBone and finance the second half of the project.[/quote]

I may just do that with the insane prices these things are getting! :shock:

Oh yeah, what about the pics of the Capitol modded electronics you've got?

Of course the Sowter, but it's got that tertiary winding for the feedback that makes it a one off. And sometimes people hardwired in the A-11's because the manual calls it out as equivalent. I'm pretty sure that's a UTC can w/an Ampex label. It's the same one in the 601's too. You could hardwire in an A-10 and have multi impedance switch too. I think the Ampex can be 150 or 500, right?

Oh yeah, what about the pics of the Capitol modded electronics you've got?

Click to expand...

Okay! Ha, I'll pull them out of the cabinet tomorrow morning and post pics here. They're pure genius! Maybe tonight...