Ampex 351 Preamp

Fabianuy · 24th October 2007, 11:22 AM

Hi, what you think about this preamp, really nice sound?, i'm looking one for vocals and instruments.

Thx

Fabianuy · 25th October 2007, 07:30 AM

Anybody?

Velvetfreddy · 25th October 2007, 02:54 PM

Great. I love mine. Use it for ribbon mics all the time. A little dark for modern music, the low midrange is beautiful and they are very 3 dimensional. Check out Electrical Audio, they have a pile of them there.

rufus13 · 25th October 2007, 03:30 PM

In a vacuum, when there is no other pre-amplifier, fine. Dark, low-quality, under-documented, Frankenstein's monster construction.

Compared to any well designed purpose-built pre-amp, about a C-minus grade. When the 351 was new, no one in any professional position would have considered using it as a mic pre.

What an AMPEX 351 electronics section has when butchered in the Electrical Audio -style is a very retro-looking face (because it is in fact, old, and once part of very expensive gear). If how your gear looks is of primary importance, then by all means pay the maximum amount on e-bone, and have at it.

The "fashion demand" for AMPEX 35x tube electronics has made it financially/logistically difficult to put together an original transport and electronics to do what the AMPEX electronics do best: record and reproduce TAPE.

Pick another design. You will have a better unit, no matter if it's new, vintage, or DIY.

Cheers.

Velvetfreddy · 25th October 2007, 03:40 PM

Hey Rufus-- might be time to switch to decaf.

They aren't that bad, even if you are a modern loving, bright, clinical type - and yes, the prices have gone up, and yes, it's a drag that people are are hacking up beautiful old classic tape machines for their pre's. What's new?

rufus13 · 25th October 2007, 04:09 PM

but I won't drink decaf.

I meant every part of the last post. I think the sonic benefits of a 351-based microphone pre do not justify the cost of the electronics/re-purpose or the loss of a tape recorder. It's not a good deal, compared to other products/designs that do the same thing.

If you record at Electrical, and use theirs, good-on-ya! Let's not pretend that the gear has all that much to do with the good results. I'd give that credit to the staff of the studio.

Check out the threads on "1960's sound". "get a vintage 1960's studio engineer" is excellent advice. Act quickly, because a 20 year old studio intern from 1969 is now 58 years old.

Cheers.

Fabianuy · 26th October 2007, 01:10 AM

Will be better to wait for a Hand Crafted Affinity 2 than Ampex? I know different hardware and different sound. but what do you think its better?

mixman499 · 26th October 2007, 01:32 AM

i've used a few that absolutely sounded like complete crap.

i used one that a friend had "modded" (not sure exactly what) and it as freaking awesome on vocals and bass guitar. def not a bright pre. was perfect for vocals...very motownish.

i have had good luck with old altec preamps. i have a few 1567a line/mix mixers that i use alot. upgraded some parts, and found some original green altec mic transformers...and they rock.

i paid i think 50 bucks for mine....i am seeing them go for aLOT more these days...but maybe you can get lucky and fine one. i found mine at a church auction...they had "updated" their sound system to a new behringer mixer. and sold the altecs.

one of my few lucky discoveries.

best of luck to ya !

jchristopherhughes

theron d · 26th October 2007, 01:59 AM

I have one, still has all the original electronics and was tested and showed to be within specs by Vark Audio -Cabin John, Md. Cool deal. Last week I had a friend do a 20 Hz-20Khz frequency response and it looked pretty flat. Slight bump in the lower freqs, also the distortion test showed 1.6 % compared to .6% distortion for my Avalon M5. Still not bad (I assume)....

I use with a Beyer M160 and it sounds great on percussion, acoustic/classical guitars. The gain is monstrous. Guess I'll keep using until the electrolytic caps give out, until then if it aint broke I aint fixing it...

Theron Day

fazeka · 25th March 2008, 10:25 PM

Theron,

Is this 351 of the Ampex 4-track you had (300 transport with 351 electronics)? If so, whatever happened to that machine?

lozion · 25th March 2008, 10:50 PM

Tried one for a mono room mic with good results...
other then that though... yes they do look cool...

charlesaustin · 26th March 2008, 01:08 AM

You have to remove all of the tape electronics from the signal path if you want it to be great, same with all of the old ampex stuff. I think it is my favorite for male vocals, of course mine has some nifty mods, but you cant get THAT sound without one. Anyone that heard one that sucked heard one with the bias and the rest of the electronics (including vu meter) still in the circuit. Get rid of the and they rock.

FFTT · 26th March 2008, 12:58 PM

The 351's seem to be the most popular because of the rather impressive face plate graphics, but actually the 403-P with Peerless transformers has better components.

The sound is big fat and warm with a bit of hair.

I also get very interesting results using my DAV BG-1 in combination with my 403-P
to add a bit of air.

In my opinion the Ampex adds life to otherwise sterile digital recordings.

Phil Cibley · 26th March 2008, 06:23 PM

Quote:

Originally Posted by theron d

1.6 % compared to .6% distortion for my Avalon M5. Still not bad (I assume)....

If I measured 1.6% distortion on any of my equipment, I'd think it was broken!

FFTT · 28th March 2008, 05:05 AM

Quote:

Originally Posted by Phil Cibley

If I measured 1.6% distortion on any of my equipment, I'd think it was broken!

Big fat and warm with a bit of hair is hardly broken, it's just alive.

waterfreddy · 12th May 2008, 05:27 AM

Hey guys, I've been checking out a couple of 351 pre's and noticed that they produce a pretty nasty clipping transistor-like distortion on the input when you send them a hot mic level (say from a guitar amp through a 57, or a loud vocal from a tube mic). When I put a 20dB pad on the mic cable just before it goes into the pre it sounds great. I've been searching up and down the web for answers to why exactly this is happening and haven't been able to come up with much. I'm assuming that the input transformer in the 351 isn't exactly equipped for modern high output mics and are getting over saturated. Does anybody have any insight into what's going on here? And, if so, is there a common mod to fix this?

Thanks!!!

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Ampex 351 Repair in LA?	aermotor	So much gear, so little time!	1	2nd March 2007 09:35 PM
Someone to service Ampex 351 pre?	polimorfos	So much gear, so little time!	11	1st August 2006 03:15 PM
Ampex 351 Load with Ribbons	laoded	So much gear, so little time!	0	24th February 2006 09:32 AM
Ampex 350/351 2 track	mizzle	So much gear, so little time!	14	21st November 2005 04:09 PM

24th October 2007, 11:22 AM	#1
Fabianuy Gear Head Join Date: Oct 2007 Posts: 50	Ampex 351 Preamp Hi, what you think about this preamp, really nice sound?, i'm looking one for vocals and instruments. Thx

25th October 2007, 03:30 PM	#4
rufus13 Gear addict Join Date: Sep 2005 Location: Portland Oregon Posts: 470	When compared to other toob/transformer pre's? In a vacuum, when there is no other pre-amplifier, fine. Dark, low-quality, under-documented, Frankenstein's monster construction. Compared to any well designed purpose-built pre-amp, about a C-minus grade. When the 351 was new, no one in any professional position would have considered using it as a mic pre. What an AMPEX 351 electronics section has when butchered in the Electrical Audio -style is a very retro-looking face (because it is in fact, old, and once part of very expensive gear). If how your gear looks is of primary importance, then by all means pay the maximum amount on e-bone, and have at it. The "fashion demand" for AMPEX 35x tube electronics has made it financially/logistically difficult to put together an original transport and electronics to do what the AMPEX electronics do best: record and reproduce TAPE. Pick another design. You will have a better unit, no matter if it's new, vintage, or DIY. Cheers. __________________ "The cost of acceptable mediocrity has come way down, but that has nothing to do with excellence." - Bob Olhsson, 01Sept2007, 12:44 PM GS post Q:What about Engineer qualifications? "I look for one that will keep his hands away from the knobs." -Norman Granz, interview R-E/P p.22 Aug 1977 "It's not how old you are, it's how well you work." Jim Williams Audio Upgrades

25th October 2007, 04:09 PM	#6
rufus13 Gear addict Join Date: Sep 2005 Location: Portland Oregon Posts: 470	I could drink less coffee but I won't drink decaf. I meant every part of the last post. I think the sonic benefits of a 351-based microphone pre do not justify the cost of the electronics/re-purpose or the loss of a tape recorder. It's not a good deal, compared to other products/designs that do the same thing. If you record at Electrical, and use theirs, good-on-ya! Let's not pretend that the gear has all that much to do with the good results. I'd give that credit to the staff of the studio. Check out the threads on "1960's sound". "get a vintage 1960's studio engineer" is excellent advice. Act quickly, because a 20 year old studio intern from 1969 is now 58 years old. Cheers. __________________ "The cost of acceptable mediocrity has come way down, but that has nothing to do with excellence." - Bob Olhsson, 01Sept2007, 12:44 PM GS post Q:What about Engineer qualifications? "I look for one that will keep his hands away from the knobs." -Norman Granz, interview R-E/P p.22 Aug 1977 "It's not how old you are, it's how well you work." Jim Williams Audio Upgrades

26th October 2007, 01:32 AM	#8
mixman499 Lives for gear Join Date: Jun 2004 Location: usa Posts: 894	i've used a few that absolutely sounded like complete crap. i used one that a friend had "modded" (not sure exactly what) and it as freaking awesome on vocals and bass guitar. def not a bright pre. was perfect for vocals...very motownish. i have had good luck with old altec preamps. i have a few 1567a line/mix mixers that i use alot. upgraded some parts, and found some original green altec mic transformers...and they rock. i paid i think 50 bucks for mine....i am seeing them go for aLOT more these days...but maybe you can get lucky and fine one. i found mine at a church auction...they had "updated" their sound system to a new behringer mixer. and sold the altecs. one of my few lucky discoveries. best of luck to ya ! jchristopherhughes __________________ "how about more of less....?" jchristopherhughes producer/engineer/mixer/sound geek myspace.com/jonchristopherhughes

25th October 2007, 07:30 AM	#2
Fabianuy Gear Head Join Date: Oct 2007 Posts: 50	Anybody?

25th October 2007, 02:54 PM	#3
Velvetfreddy Gear nut Join Date: Jan 2005 Location: Nashville Posts: 131	Great. I love mine. Use it for ribbon mics all the time. A little dark for modern music, the low midrange is beautiful and they are very 3 dimensional. Check out Electrical Audio, they have a pile of them there.

25th October 2007, 03:40 PM	#5
Velvetfreddy Gear nut Join Date: Jan 2005 Location: Nashville Posts: 131	Hey Rufus-- might be time to switch to decaf. They aren't that bad, even if you are a modern loving, bright, clinical type - and yes, the prices have gone up, and yes, it's a drag that people are are hacking up beautiful old classic tape machines for their pre's. What's new?

26th October 2007, 01:10 AM	#7
Fabianuy Gear Head Join Date: Oct 2007 Posts: 50	Will be better to wait for a Hand Crafted Affinity 2 than Ampex? I know different hardware and different sound. but what do you think its better?

26th October 2007, 01:59 AM	#9
theron d Gear Head Join Date: Jul 2006 Location: Baltimore Posts: 52	I have one, still has all the original electronics and was tested and showed to be within specs by Vark Audio -Cabin John, Md. Cool deal. Last week I had a friend do a 20 Hz-20Khz frequency response and it looked pretty flat. Slight bump in the lower freqs, also the distortion test showed 1.6 % compared to .6% distortion for my Avalon M5. Still not bad (I assume).... I use with a Beyer M160 and it sounds great on percussion, acoustic/classical guitars. The gain is monstrous. Guess I'll keep using until the electrolytic caps give out, until then if it aint broke I aint fixing it... Theron Day

25th March 2008, 10:25 PM	#10
fazeka Gear Head Join Date: Jun 2007 Posts: 37	Theron, Is this 351 of the Ampex 4-track you had (300 transport with 351 electronics)? If so, whatever happened to that machine?

25th March 2008, 10:50 PM	#11
lozion Lives for gear Join Date: May 2005 Location: Montreal Posts: 1,096	Tried one for a mono room mic with good results... other then that though... yes they do look cool... __________________ "The secret in life is to have no fear" Fela Anikulapo Kuti My Page The Furnace

26th March 2008, 01:08 AM	#12
charlesaustin Gear addict Join Date: Aug 2006 Posts: 456	You have to remove all of the tape electronics from the signal path if you want it to be great, same with all of the old ampex stuff. I think it is my favorite for male vocals, of course mine has some nifty mods, but you cant get THAT sound without one. Anyone that heard one that sucked heard one with the bias and the rest of the electronics (including vu meter) still in the circuit. Get rid of the and they rock.

26th March 2008, 12:58 PM	#13
FFTT Lives for gear Join Date: Dec 2005 Location: A stoned throw from ground zero Posts: 2,932	The 351's seem to be the most popular because of the rather impressive face plate graphics, but actually the 403-P with Peerless transformers has better components. The sound is big fat and warm with a bit of hair. I also get very interesting results using my DAV BG-1 in combination with my 403-P to add a bit of air. In my opinion the Ampex adds life to otherwise sterile digital recordings. __________________ Don't look at me in that tone of voice

12th May 2008, 05:27 AM	#16
waterfreddy Gear interested Join Date: May 2008 Posts: 4	Hey guys, I've been checking out a couple of 351 pre's and noticed that they produce a pretty nasty clipping transistor-like distortion on the input when you send them a hot mic level (say from a guitar amp through a 57, or a loud vocal from a tube mic). When I put a 20dB pad on the mic cable just before it goes into the pre it sounds great. I've been searching up and down the web for answers to why exactly this is happening and haven't been able to come up with much. I'm assuming that the input transformer in the 351 isn't exactly equipped for modern high output mics and are getting over saturated. Does anybody have any insight into what's going on here? And, if so, is there a common mod to fix this? Thanks!!!

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search
Display Modes	Rate This Thread
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode	Rate This Thread: