Messages

61

Tape Tech / Re: Possible replacement for 5532 opamp?

« on: March 14, 2012, 04:07:56 PM »

Bill,

There are maybe a dozen "new" chips - singles / duals / higher voltage (+/- 22V) versions and they come in different package styles.  Only a few like the LME49710 (single) come in a DIP package and I think will directly replace the 5534 (do get that mixed up with the 32 which I believe is the dual).  Some are available in an 8pin can which "purists" say is the best BUT is maybe 5 times more expensive.  Regarding stability, I believe they are unity gain stable but please check the spec sheet.  Have had to add a small compensating cap (200pf or so) between the output and inverting input on sopme designs but this may already be there if you are replacing op ampe in an existing circuit.  Should look at the output with a scope after any new amp changeout to see if it is oscillating / stable.

Douglas Self still LOVES the 5532/4 and his evidence in his new low noise circuit book is pretty convincing.  Also some great discussion of parts including capacitor selection.

Yea early Spring (here anyway) !!

Charles

62

Tape Tech / Re: Possible replacement for 5532 opamp?

« on: March 12, 2012, 12:12:02 PM »

Bill,

I've done a LOT of work/listening with the LME 49xxx chips and they are fantastic.  Can't tell the difference between most of them and the OP627's - and that is saying a lot

Charles

63

Tape Tech / Re: Studer A80R 1/4 INCH Cant Record.

« on: February 12, 2012, 06:39:43 AM »

Thank You:

Have you checked all the record cards carefully.  I found a shorted B+ filter capacitor on a record board that burned out a dropping resistor and basically "took down" the whole board.

Good Luck

Charles

64

Tape Tech / Re: Studer A80R 1/4 INCH Cant Record.

« on: February 11, 2012, 04:38:13 PM »

plus you spel funy

65

General Discussion / Re: I am new here

« on: February 11, 2012, 06:32:06 AM »

Welcome,

Yeah, most of us really aren't that bad!

66

Reel to Reel Tape Machines / Re: MCI JH-110b 1/4" 2-track - I can get it for $600 - pics/vids inside

« on: February 02, 2012, 06:29:40 AM »

I have had two 110's; a full one (which is now at a local recording studio) and a transport (only) which I use most every day.  The transport was originally for playback only and I added a Nortronics quarter-track head (fits in the MCI holder perfectly) so I could play those few pre-records I have.  Heads are wired out to my electronics.  Transport is very good except finicky (all analog servo circuitry will all those connectors that can go "squirrelly").  Takes about 3 minutes to change from 1/4" TO 1/2" if you have the rollers/guides/headblock.

Now for the dirty little secret - MCI used Bogen R/P heads and they are WONDERFUL.   

Charles

DO love the tape handling of the Otari MTR-10 tho -

67

Reel to Reel Tape Machines / Re: MX5050 External Tape Rewire

« on: January 28, 2012, 05:17:20 AM »

Suggest also adding a ground wire to the cables.  One end connected to the headblock as close to the playback head as you can get it - the other end to the ground lug on the preamp.  Can help reduce hum depending on your situation.  Listen for lowest hum connected / unconnected - if you end up not needing it then leave it unconnected.

Charles

68

Reel to Reel Tape Machines / Re: MX5050 External Tape Rewire

« on: January 26, 2012, 06:00:13 AM »

Hi Miks,

I'm going to see a friend on Sun who has an unmodified unit.  Will take a look and see if I can come up with any pointers.

Charles

69

Prerecorded Tapes / Re: If I have a Studer A80 2 Tracks 1/4 machine...

« on: January 18, 2012, 05:27:05 PM »

Steve,

Totally agree

Charles

70

General Discussion / Re: Dubbing "Backwards"

« on: January 18, 2012, 04:29:51 PM »

.melborp ruoy dnatsrednu t'nod I

selrahC

71

General Discussion / Dubbing "Backwards"

« on: January 18, 2012, 06:59:53 AM »

Sorry if this has been discussed before and I missed it.  Just remembered something I'd heard yyeeaarrss ago.

Story goes like this:  Each time you make an analog tape dub, you "accumulate" time delays on the new recording as the tape moves across the head in one direction and is going "relatively" slowly.  When you play back the tape or make a dub, it's always in the same direction so these delays will inevitably accumulate.

So to help counteract this a bit; when you make a dub, why not do it "backwards"?  This would "reverse" at least one set of "delays".

Any sense to this / in this?

Charles

72

Prerecorded Tapes / Re: If I have a Studer A80 2 Tracks 1/4 machine...

« on: January 17, 2012, 05:30:11 PM »

FWIW;

A long time ago I was taken to task for calling the 2 track stereo tapes 1/2 track.  This was because there were a number of pre-recorded, 1/2 track, MONO tapes released.

From then on I've adopted the convention of calling the stereo ones; 2 track stereo.

Charles

73

Tape Tech / Re: Head Azimuth Alignment

« on: January 16, 2012, 04:21:54 PM »

John,

How about if you look at the 10 or 15Khz L & R sine waves one above the other on a dual trace scope - try to get them as close together as you can - then adjust the azimuth to get the peaks/valleys of each as close "in time" as you can.

Charles

74

General Discussion / Re: WTD: To buy/rent/borrow an Otari MTR-12 Extender Card

« on: January 09, 2012, 06:17:56 AM »

Joe,

Just a thought - Have no extender but had to adjust the 7 1/2ips capstan gain on one of my 10's.  Needed to get to two internal test points to do so.  Found that there was actually plenty of room on the component side of the card to solder two jumper wires - and bring the other ends out and attach a scope to them.  A bit inconvenient but it worked.

Charles

75

Reel to Reel Tape Machines / Re: Which machine to keep, which to sell... Ampex ATR-102 / Nagra T?

« on: January 05, 2012, 06:15:17 AM »

Yeah,

Problem with the Nagra's, especially the T appears to be - they are fine if they work OK, but FORGET trying to get them repaired when they "brake" (unless you want to take out a second mortgage) .  Horror stories on other forums - unless something has changed.  Too bad!

Charles