Any noise reduction mods for the Teac 80-8?

[Beck]

As for modding in general, about everything can be improved. I have mods for the 38, 48 and Otari MX5050 too. I even mod my computer motherboards to do things they could not do stock and operate with greater stability. Some people are into modding and others not so much. You could spend that time you could be modding by watching TV or surfing the net I suppose.

 

[Tim Gillett]

@Tim I am very happy with the quality of recordings I am getting out of my Teac 80-8 but a little improvement goes a long way.
For some weird reason I turn out better quality recordings when I track to analog tape. What should I do?

Find out why that is, and why it is not so for the majority of audio recordists today. It may be that you are making some simple mistake such as clipping your digital recordings. If so, go to the basic teaching materials on this Home Recording forum. Perhaps upload a sample of some of your recordings for comment by experienced audio people.

Best wishes,

Tim

 

[Tim Gillett]

And you came to this conclusion how exactly?

And we all know about tape hiss and how to tame it. Noise gates have been used in professional environments for decades. The newer smart gates that came out after dbx and Dolby are super!

You should rephrase your reply to something like the following, Tim.

"What's a noise gate and how do you use them?"

I came to that conclusion the same way that you and everybody else did, by following the wisdom of the analog tape industry decades ago.

Why do you recommend DBX or Dolby NR if the same job could be done by single ended "smart gates"? Because you know very well that "after the fact" gates dont and never will do the job as well as the proper engineered way which always was double ended NR.

Double ended NR got the program above the noisy soup in the first place -at the recording stage. After that is too late.

I know very well the valid uses of a noise gate, which is not and never will be to take the place of double ended noise reduction in analog tape recording and other applications where noise is an issue, such as noisy telecommunications lines.

"What's a noise gate and how do you use them?"

Indeed. Once again, the floor is yours. We're all ears.

Tim G

 

[LToro]

Find out why that is, and why it is not so for the majority of audio recordists today. It may be that you are making some simple mistake such as clipping your digital recordings. If so, go to the basic teaching materials on this Home Recording forum. Perhaps upload a sample of some of your recordings for comment by experienced audio people.

Best wishes,

Tim

Hola Tim. I always perform good gain staging. I came here asking how to mod a particular piece of equipment.
Beck did an amazing job showing me precisely what I asked. I am not asking how to properly record anything, however I am no expert. How can I upload a track on this thread? Can I?

Lo mejor,

LToro

 

[LToro]

Another thing you could try, though not sure how well it will work on that machine...is to track with highs boosted (aka pre-emphasis), then on mixdown, cut back an equal amount. Find the frequency area that will mask the hiss/noise the best, and see if it works. I know some people do that when avoiding N/R or not having N/R.
Here's some info on it and on NR formats:

Tape Noise Reduction

Priceless !!! Thanks Miroslav.

 

[miroslav]

As for modding in general, about everything can be improved. I have mods for the 38, 48 and Otari MX5050 too. I even mod my computer motherboards to do things they could not do stock and operate with greater stability. Some people are into modding and others not so much. You could spend that time you could be modding by watching TV or surfing the net I suppose.

Like I said...I wasn't talking negatively about modding gear (I've done some myself over the years)...I was just commenting on how some people go crazy with it, and then in the end move on to something else anyway.
That's why I would weigh it all out...and if you like to mod, then do it...but if want to just get on with recording, it might be better to switch gear or something.

I remember this one guy who spent a lot of time modding his board and studio...tried real hard to upgrade his semi-pro gear to a more pro level....
...then one day he was all bummed out.
Turns out his studio caught fire from something he did, some electrical thing...and everything was gone.
He said..."I've spent so much time, effort and money trying to make things better, fixing/upgrading my gear....and now it's all gone...and all I ever really wanted to do was be a songwriter and make some music."
It was sad...but also kinda funny.

So Beck...what mods do you have for the 5050?
I have the last model ever made...the BIII...so I would think it was their best effort, but I'm curious what can be done to it to improve it.
I have some other gear that I need to do some work on....but man...I just get so behind on the actual recording, that sometimes it's frustrating!!!

 

[Beck]

I came to that conclusion the same way that you and everybody else did, by following the wisdom of the analog tape industry decades ago.

Why do you recommend DBX or Dolby NR if the same job could be done by single ended "smart gates"? Because you know very well that "after the fact" gates dont and never will do the job as well as the proper engineered way which always was double ended NR.

Double ended NR got the program above the noisy soup in the first place -at the recording stage. After that is too late.

I know very well the valid uses of a noise gate, which is not and never will be to take the place of double ended noise reduction in analog tape recording and other applications where noise is an issue, such as noisy telecommunications lines.

"What's a noise gate and how do you use them?"

Indeed. Once again, the floor is yours. We're all ears.

Tim G

Stop telling me what I think, Tim G. You obviously have a comprehension problem, and you know it. I'm not the first person who has told you.

No, you really don't understand gates/expanders and how they're used, quite obviously. Tim, you know nothing. You came here 7 years ago with nothing but misconceptions. 7 years later you have even more misconceptions. I can tell the difference between a poser who's learned everything on web forums and someone with decades of experience. The same as I can tell what part of the country a person is from by their accent. If I was visiting New Jersey and a fellow came up to me with a southern accent and claimed he was born and raised in Jersey I would know he was lying, just like I know you are when you try to speak from experience. You are so unaware you don't even know how obvious your pretending is to others. You only fool yourself.

You're as welcome here as anyone else to come here and ask questions... but, when you you start posing as an expert you will be called on it. When people come hear seeking advice from the many good members here that have been there and done that, why don't you just sit and listen and you would actually learn something? In 7 years you could have become a helpful contributing member, but instead you are a persistent resident troll. Every time someone asks a question you give them a difficult time for using analog at all. If the current moderators understood why this forum was created and called "Analog Only" in the first place you would be banned from this sub-forum.

LToro has handled you well. Others get terribly mislead by you and it's a shame they get so confused before they can even begin.

So LToro, meet our resident troll, Tim Gillett. He knows nothing. He is a pretender. He has some limited experience in a very isolated area of recording, perhaps cassette duplication. He's not been anywhere else. He's not done anything but hang out in forums and he gets things so bass ackwards there's no untangling it. You can't believe a word he says. Now Tim, shake hands and say, nice to meet you.

 

[Beck]

Like I said...I wasn't talking negatively about modding gear (I've done some myself over the years)...I was just commenting on how some people go crazy with it, and then in the end move on to something else anyway.
That's why I would weigh it all out...and if you like to mod, then do it...but if want to just get on with recording, it might be better to switch gear or something.

I remember this one guy who spent a lot of time modding his board and studio...tried real hard to upgrade his semi-pro gear to a more pro level....
...then one day he was all bummed out.
Turns out his studio caught fire from something he did, some electrical thing...and everything was gone.
He said..."I've spent so much time, effort and money trying to make things better, fixing/upgrading my gear....and now it's all gone...and all I ever really wanted to do was be a songwriter and make some music."
It was sad...but also kinda funny.

So Beck...what mods do you have for the 5050?
I have the last model ever made...the BIII...so I would think it was their best effort, but I'm curious what can be done to it to improve it.
I have some other gear that I need to do some work on....but man...I just get so behind on the actual recording, that sometimes it's frustrating!!!

Yeah, I hear ya Miro. If your goal is to make music you can get carried away with mods. I have to balance the musician and the engineer in me, but we are all different in the regard. I'm more of a Tom Scholz or Craig Anderton... musician, composer, inventor, engineer. So I wear many hats in the studio. Sometimes I will admit I wish I didn't, so I could have someone else do something and I could watch Night Gallery reruns more often.... or the Brady Bunch.

The best mod for the MX5050 is to replace the relays with a sealed type. I have the part numbers here somewhere on my overcrowded hard drive. I'll look them up and get them to you. The unsealed relays eventually will get some corrosion inside and start acting up, which effects the audio in very subtle but negative ways. Other than that the 5050 is a solid machine. For mutitrack you can always replace a good bit of the carbon resistors with metal film resistors in the signal path. Only the ones in the signal path matter. For 2-channel mixdown deck this doesn't matter as much. But with multiple channels... 8 and up you get a significant cumulative noise effect. Same goes for mixing boards. You can significantly reduce the noise with better op-amps and metal film resistors in most gear if they don't already have the best stuff. Manufactures cut corners when they're dealing with mass production. It's a fact of life. The owner can spend a bit more and if good with a soldering iron can upgrade some standard parts to grade A parts. I once new someone who didn't know how to mod his equipment at all, but he smoked in bed and lost everything to a fire. Fire moves in mysterious ways.

 

[ecc83]

Oh dear!
Well, I am just an old valve amp tech with a very musical son!

From my point of view it would be nice to know just how noisy the machine is? A figure ref line level can easily be measured using a DAW.

But tape machine noise has various sources. Record/playback hiss of course and you would expect replay amp noise to be well below moving tape noise but some information given here suggests that this might not be the case? The first test has to be new, bulk erased tape noise. If that is up to specc' then we are looking at noisy record amps or a distorted bias waveform. You can't always go by low "paused" noise because mutes may well be switched in.

Lasty and this almost certainly does not apply in this case, but blanket suggestions of op amp swops can lead to tears. The NE5532 has for instance a typical supply current pull of 8mA (16mA max) whereas the 4558 is 3mA typical (6.6max). Replacing a shedload of chips can result in a power supply problem. Then not all op amps are unity gain stable, i.e. the NE5534.

Dave.

 

[Tim Gillett]

Good comments Dave. You're dead right. We have to be specific about the possible sources of noise. And as Miroslav says, there are cost/benefit issues. We have to live in the real world.

Upgrading things like amps in a tape machine are only worth it performance wise if they are actually the real or main cause of the problem. You can upgrade a chip that might have a 70 db S/N to a quieter one with 80 S/N.
But if a good tape on that machine is only good for 60db S/N, the advantage of the quieter chip is mostly swamped by tape noise anyway. In this case you would only yield a tiny improvement if that.

Many years ago when I couldnt afford a Nagra, I had an early 60's Akai X-IV portable stereo reel to reel machine. It had the early germanium transistors all through it. They were fine in the output stages but incredibly noisy in the preamps, so much so that the main source of noise in record or playback, was transistor noise. Even more noise than tape noise.
The amps were barely adequate for noisier early 60's tapes but the later low noise tapes of the 70's and 80's exposed the weaknesses of the noisy amps even more. It was hardly worth using the lower noise tapes as they ended up sounding just as noisy as the earlier ones.

Once I had worked out the noise was coming from the germaniums, upgrading to the better silicon ones was a no brainer. Since it was a stereo machine I could keep the left track bog standard and only mod the right track, so I had a control or reference to keep me honest. The improvements had to be measureable and empirical. If there was no significant improvement or it was worse, I could always backtrack to standard.

After upgrading the trannies to quieter types, that exposed more low down noise coming from the DC motor which was inducing into the playback head. So I added more mumetal shielding to the small motor, re routed wires and added a metal interference shield around the play head track change switch. That dealt with that problem.

I had achieved my goal. The main residual noise was now tape noise/bias noise, which was what I had aimed for.

It's not always well understood that if it's not the real weak link in the signal chain, upgrading that component will make little or no difference. But if it is the weak link, or one of them, that's different. It might be worth an upgrade.

The tape type, tape speed and track width also made a difference. The Akai X-IV was a 1/4" quarter track machine. If it had been half track or full track, or ran at faster tape speeds (or even more all three) the reduced tape noise may have justified quieter record circuitry.

On the other hand, the opposite applies to the playback circuit. With a weaker playback signal such as with slower tape speed or a narrow track, you wanted to get repro amp noise down as low as you could to not compete with the weaker signal from the head. So cassette machines with their slower tape speed and narrower tracks need a quieter playback amp to make the most of the weaker playback signal. Reel to reel machines running faster speeds and wider tracks arent nearly so fussy about preamp noise.

It's also good to quantify the improvement. So a certain improvement might have reduced broadband noise by 5db, either weighted or unweighted. So a 5 db reduction of noise was not to be sneezed at. But reducing the amp noise to 20db quieter in this case - if it were possible - would have been be a waste of effort. You would never hear the improvement.

Tim

 

[TASCAM MAN]

Hola,

Once again I apologize for my English skill set. Ok so I have a recently serviced Teac 80-8 everything sounds fantastic however the noise floor is somewhat hight; even if I hit the tape hard you can still hear some hiss. The type of music is Latin soul nothing loud that could help mask the hiss.
I usually dump the tracks in my computer to further manipulate sound (noisy reduction plug ins by izotope do the job) But I question If there is a mod out there to reduce the noise floor of the machine. Thanks in advance

LToro.

I didnt read all the answers to your post but,I had the 2nd generation Tascam 38 that did NOT have noise reduction and made plenty plenty great sounding recordings.Id be willing to bet that the noise specs on the 38 are lot better and with no hassle of using noise reduction units

 

[Lt. Bob]

Stop telling me what I think, Tim G. You obviously have a comprehension problem, and you know it. I'm not the first person who has told you.

No, you really don't understand gates/expanders and how they're used, quite obviously. Tim, you know nothing. You came here 7 years ago with nothing but misconceptions. 7 years later you have even more misconceptions. I can tell the difference between a poser who's learned everything on web forums and someone with decades of experience. The same as I can tell what part of the country a person is from by their accent. If I was visiting New Jersey and a fellow came up to me with a southern accent and claimed he was born and raised in Jersey I would know he was lying, just like I know you are when you try to speak from experience. You are so unaware you don't even know how obvious your pretending is to others. You only fool yourself.

You're as welcome here as anyone else to come here and ask questions... but, when you you start posing as an expert you will be called on it. When people come hear seeking advice from the many good members here that have been there and done that, why don't you just sit and listen and you would actually learn something? In 7 years you could have become a helpful contributing member, but instead you are a persistent resident troll. Every time someone asks a question you give them a difficult time for using analog at all. If the current moderators understood why this forum was created and called "Analog Only" in the first place you would be banned from this sub-forum.

LToro has handled you well. Others get terribly mislead by you and it's a shame they get so confused before they can even begin.

So LToro, meet our resident troll, Tim Gillett. He knows nothing. He is a pretender. He has some limited experience in a very isolated area of recording, perhaps cassette duplication. He's not been anywhere else. He's not done anything but hang out in forums and he gets things so bass ackwards there's no untangling it. You can't believe a word he says. Now Tim, shake hands and say, nice to meet you.

^^^^^^^ this ^^^^^^^

 

[miroslav]

I know there's some strong differences of opinions here....but let's try and not let it blow up.

I think there are many mods that work...that can improve things...but I also think there are folks who just go too far sometimes with insignificant gains, so that's why I say you have to weigh it all out.

I have my aging M3500 (it's 22 years old) that still works and hasn't had a single obvious issue from day-one (knock on wood)...but I do think at this point the age is starting to affect some of the sonics, that I may need to do some work, but man, it's a LOT of work considering 24 channels + master section....so I'm weighing out.
I might rather buy something used but better (top pro quality) and do work on that to compensate for age...rather than try and revitalize my M3500.
That's kinda what I was getting at when I said it might not be worth the effort/time/cost on the 80-8....but I honestly don't know that machine and what can/can't be done or how easy...so on that I defer to Beck and those people who do.

I think we all wear many hats in the home-rec world, but at some point we each lean in the direction (wear that hat often) that appeals the most to us. If you are primarily a guitar player, but you like to record....you may not want to spend a lot of effort/time/cost on becoming also an electrical technician just to mod a piece of gear.
Likewise, if you really love to build/repair/mod gear...you end up doing that more than you do the guitar playing!

It's a struggle at times for many of us...which hat to wear today, and how well can we wear it...or should we be wearing it at all!

 

[Beck]

Lasty and this almost certainly does not apply in this case, but blanket suggestions of op amp swops can lead to tears. The NE5532 has for instance a typical supply current pull of 8mA (16mA max) whereas the 4558 is 3mA typical (6.6max). Replacing a shedload of chips can result in a power supply problem. Then not all op amps are unity gain stable, i.e. the NE5534.

Dave.

Thanks Dave and that is a very good point about blanket swaps. So just to clarify, the NE5532 replacement mod for the 80-8 has been recommended and routinely done for at least 25 years that I know of, maybe longer. The 4558 was seen as a limiting factor pretty early on. The PS on the 80-8 is thankfully quite beefy and more than capable of the extra pull from the 5532. This mod became popular as people were trying to squeeze out that last bit of performance from the aging 80-8. Another popular mod was to replace the stock heads with an aftermarket version made by Saki, but that is no longer an option as they don’t make heads anymore. And Tascam’s next generation heads made for the 38 were superior to the Saki. You will often find 80-8’s with the Saki head. If you have one that’s great because they sound a bit better and last longer.

As for other op-amp upgrades, for budget equipment you can really improve on things... IF you know what you're doing when substituting op-amps or are aware through reliable sources of a common successful mod for a specific piece of gear. I haven't come across a vintage Tascam mixer yet that can't handle the NE5532 or the NJM4580 if the original op-amp is 4558 or 4560. Results will vary with other products.

Where people get into trouble is using what I jokingly call the "Video ready" op-amps with slew rates and current draw off the charts. Like some of the Jim William’s mods. They aren't for the beginner and many of those I just plain wouldn't do because I think it's overkill.

I'm very conservative when it comes to part substitution. For example, the improvements on the 4558, like the 4570 and 4580 are no brainers in most cases. These are simply the newest generation of the 45xx series and are well suited to bring real improvements while keeping the character of the device basically the same and within the the design capabilities.

As with everything I recommend spending a lot of time in the research phase before reaching for a soldering iron. And that's one reason why we're here... to help with that process. We don’t blindly recommend op-amp upgrades across the board. My recommendations will be very specific, based on common upgrades I’m aware of from working in the field and those I’ve done myself.

LToro seems to know what he's doing. He simply asked if anyone knew of any mods for a specific machine... the 80-8, and I answered his question with what I know. I think he can handle the rest. It's very simple. Make sure the deck is calibrated to spec before changing out the op-amps. Afterwards fine-tune the calibration to get it back in spec with the new op-amps. If the OP has any further questions about the mod I'll be here to answer them. These are the kind of questions and topics I wish we had more of in this "Analog Only" forum.

 

[Lt. Bob]

the thing that anti-mod folks sometimes fail to recognize though, is that often none of that cost/benefit stuff is even relevant.
It's the DOing of it that appeals to whoever is asking. For instance ...... I'm getting ready to spend some significant time and probably money getting my 3340 and 2340 up to snuff (probably gonna bug you a bit over that Beck ).

Why?
Because I want to. That's really the only reason.
And I feel "because I want to" is a perfectly valid reason for doing something.

Very often the motivation is simply a desire to do it without regard for what you'll do with once you're thru., "

 

[Beck]

the thing that anti-mod folks sometimes fail to recognize though, is that often none of that cost/benefit stuff is even relevant.
It's the DOing of it that appeals to whoever is asking. For instance ...... I'm getting ready to spend some significant time and probably money getting my 3340 and 2340 up to snuff (probably gonna bug you a bit over that Beck ).

Why?
Because I want to. That's really the only reason.
And I feel "because I want to" is a perfectly valid reason for doing something.

Very often the motivation is simply a desire to do it without regard for what you'll do with once you're thru., "

Yes exactly! There are many good reasons to participate in forums like this. And some members don't even get into the music side. They are hobbyists or more from the engineering side and the machines are an end to themselves. For some, vintage gear is like classic cars. You mess with it, soup it up, and by all means keep it washed and waxed even if you don't drive it.

The only reason one should not be on this forum is to troll and spew ant-analog ignorance every chance they get. Something is wrong with that picture. And no one should poison a thread because of an agenda or phobia, like fear of modding or fear of degaussing, etc.

 

[LToro]

Thanks Dave and that is a very good point about blanket swaps. So just to clarify, the NE5532 replacement mod for the 80-8 has been recommended and routinely done for at least 25 years that I know of, maybe longer. The 4558 was seen as a limiting factor pretty early on. The PS on the 80-8 is thankfully quite beefy and more than capable of the extra pull from the 5532)

Beck thanks again !! My man!! Seems like a very easy mod. I am
Ok with the soldering gun and I can easily get the machine back to spec.
Looking forward. This is a very exciting forum by the way

I appreciate everybody's input. But I do have to agreed with Beck the last thing I want is somebody recommending me to go back to digital. And yeah Beck is right, what the heck this is the analog forum. I stay analog.

My father who's now 66 yrs old (started on analog switching to digital in the 90's) can not understand why on earth I want to record on analog machines.

I like analog machines they sound better than DAWs. A computer will never sound as good as fine tune Teac or Tascam analog tape recorder. Yeah it -also- drives the old man crazy jeje.

As always sorry about my Ingles
Home recording rocks!

Lo mejor,

LToro.

 

[LToro]

I didnt read all the answers to your post but,I had the 2nd generation Tascam 38 that did NOT have noise reduction and made plenty plenty great sounding recordings.Id be willing to bet that the noise specs on the 38 are lot better and with no hassle of using noise reduction units

Hola TASCAM MAN! Not to long a go I got my 80-8 back from New Jersey Teac/Tascam. I spend good money to have it back to spec. I also can get great recordings out of my Teac. I also have Tascam 38 that I was thinking of selling but perhaps I can keep (mi esposa probably kills me) I like the looks feel and slightly fatter sound I get out of my 80-8. I know the 38 have some fans but so does the 80-8. Anyways thanks for the help and is very nice to meet this community that welcomes me and my bad English Lo mejor!

 

[TASCAM MAN]

Hola TASCAM MAN! Not to long a go I got my 80-8 back from New Jersey Teac/Tascam. I spend good money to have it back to spec. I also can get great recordings out of my Teac. I also have Tascam 38 that I was thinking of selling but perhaps I can keep (mi esposa probably kills me) I like the looks feel and slightly fatter sound I get out of my 80-8. I know the 38 have some fans but so does the 80-8. Anyways thanks for the help and is very nice to meet this community that welcomes me and my bad English Lo mejor!

Well I always wanted one of them 80-8s and I know it has made many records in the pass and I beleive you will to !!

 

[Tim Gillett]

If the current moderators understood why this forum was created and called "Analog Only" in the first place you would be banned from this sub-forum.

Miroslav (and other HR Moderators if it applies), it seems Tim Beck has a problem. Apparently you dont understand the meaning of "Analog Only" as it was originally intended.

This issue occasionally gets aired on this forum. Perhaps it would be timely for you as Moderator to explain the official position as to what "Analog Only" signifies.

Is it a merely descriptive title referring to the sorts of analog based recording gear discussed here - as the rest of the title goes on to suggest - or is it meant to be taken more as a political or tribal statement such as "Analog Tape Rules OK!" ?

Would you care to discuss your understanding of this?

Thanks

Tim G