Topic: CSB's > PCM-M1...Will it work?

[Sean Gallemore]

the mic-in on the M1 will provide power (i think) but it is not recommended

Schwizzilly, please elaborate...

it's a shitty preamp.   That better?

M1 = "Shitty preamp"

The M1 has the same preamp circuitry as an SBM-1 which is considered a very respectable preamp.

Again, please elaborate...

if you look at my first post, I don't give an opinion, only a recommendation.  I did that for a reason.  I don't need to uselessly defend myself.  I know what I prefer and that's the line-in.  Why do I need to explain myself?  The M1 preamp is not respected.  Next to no one (that I know of) uses it and it is known to suck copious amounts of donkey dick between -6 and 0 dB.  That would force one to use only 15 or even 14 bits of data, and that's something I don't agree is necessary.

that is the reason for my recommendation.

[Brian Skalinder]

if you look at my first post, I don't give an opinion, only a recommendation.  I did that for a reason.  I don't need to uselessly defend myself.

Stop posting while drinking, Schwill.    I personally don't think it's useless helping people understand the reasons for opinions and/or recommendations.

I'm unfamiliar with and don't recall seeing a thread on the issues with the M1 preamp between -6dB and 0dB, hmmmm...maybe I'll have to break down and search to see if I can find one.

[George]

the mic-in on the M1 will provide power (i think) but it is not recommended

Schwizzilly, please elaborate...

it's a shitty preamp.   That better?

M1 = "Shitty preamp"

The M1 has the same preamp circuitry as an SBM-1 which is considered a very respectable preamp.

Again, please elaborate...

if you look at my first post, I don't give an opinion, only a recommendation.  I did that for a reason.  I don't need to uselessly defend myself.  I know what I prefer and that's the line-in.  Why do I need to explain myself?  The M1 preamp is not respected.  Next to no one (that I know of) uses it and it is known to suck copious amounts of donkey dick between -6 and 0 dB.  That would force one to use only 15 or even 14 bits of data, and that's something I don't agree is necessary.

that is the reason for my recommendation.

Yep, this will definitely draw new people to taping.  

He wasn't asking for you to defend yourself, he just wanted some specific info as to why the mic in stinks.   Brian Skalinder did exaxtly that and a +T to Brian.

[Sean Gallemore]

taken directly from the oade website:

"When I record mic in on my machine I get a distorted signal even when my levels never go over 0db, why ?


      Most portable DAT machines are designed for a wide range of applications. Unfortunately, they do not include recording live rock n' roll at high SPL's. The input to the mic preamplifier overloads and is the cause of distortion. The mic preamp is before the record level control, so its gain is not adjustable. With a fixed gain structure the mic preamp can be overdriven and the level meter will not show it. This is a common problem with the Sony D3/7/8/D100/PCM-M1 and the Tascam DAP-1. Oade Audio offers performance upgrades available for both of these models that will eliminate this problem and lower the noise floor of the preamp. This offers the user freedom from overload distortion and less noise !! "

[Sean Gallemore]

I hope that is more specific, and I'm sorry for acting like a jackass, but I have that right dammit!

[Brian Skalinder]

"When I record mic in on my machine I get a distorted signal even when my levels never go over 0db, why ?

This is the "brickwalling" issue as I understand it.  I don't understand what does this has to do with the -6 > 0 dB range when running mic-in.  Help?

[Sean Gallemore]

I guess we'd have to talk to doug.

Either way, it takes a mod according to the Oade Bros. to get it to work properly at high SPLs.

[Sean Gallemore]

you can see in the first sentence where it refernces -6dB as the number to not go over.  That is where I got my -6 to 0 db theory.

"Oade Brothers Audio Performance Upgrade

      Here is a little information on a problem with Sony D7/8/100/PCM-M1's known as "brickwalling" . Many of you know that to record thru the D7/8/100/M-1 mic inputs and go over the -6 level on the level meter is bad news. Here is why, the mic preamp overloads. It is NOT possible to fully utilize the dynamic range of these digital recorders thru the mic inputs. The stock D7/8 mic preamp overloads with a -15 db input level when set on the low sensitivity setting. They overload at -35 db when set on the high sensitivity setting. The D100/M1 mic input overloads at -20db with the pad on and -40db with it off (i.e. set to 0 db). No matter which mics you use or what the signal source is, this is true. It takes a -10 db input signal to get to 0 db on the D7/8's meter using the line level inputs even with the record level knob at its highest setting. It takes a -5db input signal to get to 0db on the D100/M1. As you can see there is a 5 to 15db "hole" in the gain structure of this design.

      This is why we came up with the Oade Brothers Audio (Hi-FI Sales & Svc.) D7/8/100/PCM-M1 mic preamp upgrade. Want to enjoy the FULL dynamic range of your D7/8/100/PCM-M1 with ANY microphones ? Then ask about our upgrade!

      The upgrade rebuilds the mic preamplifier completely in the D7/8 and the D100/M-1. This upgrade does not require cutting any traces or adding any jumpers. The unit which we modify looks very much the same as a stock unit. The sound is what changes ! We use a very hi quality parts and test each unit after the upgrade. We have found the upgrade will lower the noise floor of the preamp (i.e. you get less hiss in your tapes). If requested we will also increase the current capacity of the bias voltage supply for use with the well loved Panasonic mic capsule. The stock bias resistors are also change to comply with Panasonic manufacturers spec. These extras are provided at no additional charge. We feel this offers the end user the very finest in sound quality and convenience possible in an easy to use and reliable package ! The cost of this upgrade is $125.00 or $100.00 with the purchase of a new deck. "

[George]

I hope that is more specific, and I'm sorry for acting like a jackass, but I have that right dammit!

haha, i can hear you now: "I am an American and i have the right to be a jackass!"

(assuming you are an American)  

[dklein]

Here's the same thing a different way:
There is a hole in the gain structure - the line in providers a certain range of gain and the mic in provides another range of gain (at a higher level).  But...in between the highest line in setting and the lowest mic in setting... there is a gap.  This gap tricks people into switching to the mic-in setting so they can get 'full range' on their meters.  

Then the second problem kicks in - you throw a decent level signal into the mic-in setting and it overloads the preamp.  It is too much for the preamp to handle and the signal just clips to maximum level of the preamp output (brickwalling).

Because the preamp and the a>d are separate, you can still adjust the levels when you're brickwalling, and they can be adjusted so that they don't clip the a>d, but they sound like crap because they're brickwalling on the preamp.  If you had input level meters on the preamp you could see that.

So, any preamp can be brickwalled if you overload the input.  The Sony DATs sucker people into doing that because you don't see enough level from the line in and then switch over to the wimpy preamp.  Low sensitivity mics like CSBs tend not to overload mic inputs.  The other alternative is to modify the input stage to address the gain hole.

[zhianosatch]

+T dklein