Any affordable device that boosts -10dBV level to +4 studio level without introducing extra noise?

[A800]

@A800 Thanks, but I don't know about that. Behringer isn't exactly known for extreme quality, and a tube doesn't make me think of a neutral voltage increase either. Correct me if I'm wrong tho.

My unit is almost 20 years old, still functions as new.
I didn't notice a decrease in SQ otherwise it would 've been gone long ago.

 

[Blumlein 88]

What is your -10dbV source? It may already have a noise floor above the Fireface. In which case the 9db gain is just boosting the source noise, and not reducing the total dynamic range of your source.

To explain further, if your source component has 100 db of dynamic range, and you boost it +9 db the top level goes up 9db and so does the noise floor of the source. So you still have 100 db dynamic range which will fit into the Fireface window of 113 db dynamic range. It will look like you raised the noise floor in an FFT, but the noise is actually in the source.

If the source has more than 113 db dynamic range it won't fit into the smaller dynamic range window.

 

[kartoffelmann]

My unit is almost 20 years old, still functions as new.
I didn't notice a decrease in SQ otherwise it would 've been gone long ago.

I'm sure it sounds fine but I'm looking for something that performs well beyond the audible range. My UFX+ already sounds good with the gain, I just want to get the noise floor down even in the ultrasonic range. I'm not very confident that Behringer would help me do this.

What is your -10dbV source? It may already have a noise floor above the Fireface. In which case the 9db gain is just boosting the source noise, and not reducing the total dynamic range of your source.

In this case you're right, it already has one above the Fireface in the audible range. It's basically a stereo amplifier with a phono preamp that I use. However I don't want my current equipment to be the standard by which to decide, since it's relatively cheap stuff comparatively. Plus, in the ultrasonic range that device outputs next to no noise, so the Fireface noise level is very easily above it. (talking frequencies leading up to 96kHz in the 192 kHz operating mode). The high frequencies reach -100 dB even with a 65k FFT size thingy (higher makes it lower I think?) and on a spectral audio display this looks very ugly. Hell, some old E-MU 0404 (or similar) has a high frequency noise floor under -120 and my old FF800 has about -115. -100 is just not something I'm happy with. I know it's not audible but I just want to preserve the signal as well as possible for archival.

 

[A800]

I'm sure it sounds fine but I'm looking for something that performs well beyond the audible range. My UFX+ already sounds good with the gain, I just want to get the noise floor down even in the ultrasonic range. I'm not very confident that Behringer would help me do this.

The measurements would surely be worse than those from the RME.

 

[levimax]

Actually, thinking about it, the SMMDB unit of Jensen Transformers says that it produces Mic Level. The Mic inputs of the UFX+ actually have 2 dB more dynamic range in the tech specs so if I could use those without gain, that might be even better than the Line inputs. But is Mic Level a normed thing? What is the likelihood that I will end up having to use gain again?

Reading more about what you are trying to do it is hard to say. The transformer will convert unbalanced to balanced and isolate the units grounds and eliminate ground loops. If your noise is ground loop related the transformer will work for you but if the noise is from the stereo amp no matter what you use to increase gain it is going to amplify the noise. Maybe you should get a new and quiet phono pre-amp with balanced output to solve your problem at the source?

 

[Blumlein 88]

Well you sort of can't get there from here.

Suppose both devices had 100 db dynamic ranges, and you needed to boost one by 12db. You loose nothing if your gain device adds no noise. XFMRs can come close, other wise you'll usually add 3 db of noise or so with good devices. So you'd only be able to maintain 97 of the original 100 db of dynamics.

If your one device had 100 db of DR, and the lower one had 120 needing 12 db of boost. You loose dynamic range even if your gain adds nothing. You'll only get 100 db at best.

If your device needing a 12 db boost has 100 db and the other device has 120 db of DR, you can fit it inside the window to achieve close to the same 100 db of the original signal. Again probably with a 3 db or so loss. Otherwise what you are asking for a boost to increase the dynamic range in the original source which isn't possible.

 

[kartoffelmann]

Reading more about what you are trying to do it is hard to say. The transformer will convert unbalanced to balanced and isolate the units grounds and eliminate ground loops. If your noise is ground loop related the transformer will work for you but if the noise is from the stereo amp no matter what you use to increase gain it is going to amplify the noise. Maybe you should get a new and quiet phono pre-amp with balanced output to solve your problem at the source?

Well my problem isn't the noise from the source. I'm totally fine with that being amplified along with the signal, since that doesn't really affect the SNR of the source to my understanding. What I am not fine with is the high frequency noise of the UFX+ leading up to 96 kHz and reaching -100 dB that wasn't there in the source to begin with. So the higher I can get the level pre-Fireface the lower that noise should be.

 

[kartoffelmann]

Well you sort of can't get there from here.

Suppose both devices had 100 db dynamic ranges, and you needed to boost one by 12db. You loose nothing if your gain device adds no noise. XFMRs can come close, other wise you'll usually add 3 db of noise or so with good devices. So you'd only be able to maintain 97 of the original 100 db of dynamics.

If your one device had 100 db of DR, and the lower one had 120 needing 12 db of boost. You loose dynamic range even if your gain adds nothing. You'll only get 100 db at best.

If your device needing a 12 db boost has 100 db and the other device has 120 db of DR, you can fit it inside the window to achieve close to the same 100 db of the original signal. Again probably with a 3 db or so loss. Otherwise what you are asking if for a boost to increase the dynamic range in the original source which isn't possible.

I understand, thanks for elaborating. I still think it's a good idea to do what I'm trying to do, assuming it's possible.

Any thoughts about the quote I posted from the Jensen site saying that it's not a good idea going from -10 to +4 as it will increase distortion etc.? The transformer route sounded like the perfect thing to do up until I read that. Now I'm not so sure anymore. If the transformer route won't work out I think I'll just end up buying an old Fireface 800 with the -10 dBV mode again, or try and get another good ADC.

 

[kartoffelmann]

Now I'm looking at the devices mentioned on that site, the Rane “Balance Buddy” or Ebtech “Line Level Shifter”. But I can't find any detailed frequency response graphs and the THD of the Ebtech is "under 0.002%", which - correct me if I'm wrong - is pretty high and ultimately makes this whole thing pointless because I might end up with a lower noise floor but a ridiculous amount of distortion. Even the Jensen one only says "under 0.001", but the Fireface's THD is 0.00032 according to the manual... and I think the Jensen doesn't even do a level shift.

I guess I just need a better ADC in the end. Maybe I can figure out how to build that PCM444EVM thingie. I wonder how that thing behaves at -10 dBV...

 

[Blumlein 88]

I understand, thanks for elaborating. I still think it's a good idea to do what I'm trying to do, assuming it's possible.

Any thoughts about the quote I posted from the Jensen site saying that it's not a good idea going from -10 to +4 as it will increase distortion etc.? The transformer route sounded like the perfect thing to do up until I read that. Now I'm not so sure anymore. If the transformer route won't work out I think I'll just end up buying an old Fireface 800 with the -10 dBV mode again, or try and get another good ADC.

The xfmr problem is simply the impedance change involved. It might bother one piece of gear and not another. My guess is in your situation it would be a problem for your source component.

I don't see how if you had the older component with the -10dbV input that you'll gain anything. The noise level of your source is going to be higher than the RME device and even without gain you aren't going to benefit (except maybe in the ultrasonic noise levels). You could always record at 192 khz and then apply a roll off filter at 48 khz to kill the noise after the fact. There is nothing musical beyond 48 khz on an LP its just noise anyway.

 

[kartoffelmann]

The xfmr problem is simply the impedance change involved. It might bother one piece of gear and not another. My guess is in your situation it would be a problem for your source component.

I don't see how if you had the older component with the -10dbV input that you'll gain anything. The noise level of your source is going to be higher than the RME device and even without gain you aren't going to benefit (except maybe in the ultrasonic noise levels). You could always record at 192 khz and then apply a roll off filter at 48 khz to kill the noise. There is nothing musical beyond 48 khz on an LP its just noise anyway.

Mmmh, I see.

As I said, the noise level of my source is not supposed to be the measuring stick because I might very well want to upgrade it some day.

I'm just not happy with this higher noise level in the Fireface UFX+, that's all. I realize it's being picky and pedantic, but that's simply how I feel about it. Applying a roll-off I would lose the whole point of recording at 192 kHz in the first place. I know most people think this is pointless and that LPs don't have information there etc. yada. I just want to archive it as well as possible. You never know what technology (see machine learning) might come around in the future that will be able to profit from a good well-preserved ultrasonic range.

And also, there might be other stuff I will want to digitize at some point in the future and I want to be prepared as well as possible. I thought the UFX+ would be an upgrade over a 16 year old unit, sadly it was a downgrade.... so I guess maybe I'm just frustrated by my buying decision and trying to overcompensate ... let me!

 

[Kal Rubinson]

I would just use the Behringer MIC2200(V2).
https://www.bhphotovideo.com/lit_files/84914.pdf
Very good sound.
Variable low cut, parametric EQ, phase...

OK.

It has a tube also.

Oh. Never mind.

 

[A800]

OK.
Oh. Never mind.

LOL!

 

[levimax]

Mmmh, I see.

As I said, the noise level of my source is not supposed to be the measuring stick because I might very well want to upgrade it some day.

I'm just not happy with this higher noise level in the Fireface UFX+, that's all. I realize it's being picky and pedantic, but that's simply how I feel about it. Applying a roll-off I would lose the whole point of recording at 192 kHz in the first place. I know most people think this is pointless and that LPs don't have information there etc. yada. I just want to archive it as well as possible. You never know what technology (see machine learning) might come around in the future that will be able to profit from a good well-preserved ultrasonic range.

And also, there might be other stuff I will want to digitize at some point in the future and I want to be prepared as well as possible. I thought the UFX+ would be an upgrade over a 16 year old unit, sadly it was a downgrade.... so I guess maybe I'm just frustrated by my buying decision and trying to overcompensate ... let me!

OK now it makes sense what you want and I won't argue with you about what you actually need . Seems like a different ADC is your best bet... not sure which ones publish specs @ 100 kH. The one you have looks pretty good actually.

When ever I think about digitizing my vinyl collection I don't because I think some day I will have a better TT or Cart or Tone Arm and will have wasted my time. Now you made me think that maybe in the future there will be some AI optical system able to extract all the analog goodness trapped in the dirty and rough old grooves.

 

[kartoffelmann]

Haha thanks for letting me indulge my madness!

So from what I've been able to learn, the PCM4222 evaluation board is the way to go. I learned that Ross Martin made a simple ADC using that chip/board, but it doesn't seem like he's doing it any longer and I can't find any for sale either. They were priced very fairly at unter $250.

Then I found the PS Audio nuWave Phono Converter ... now that thing looks very intriguing, but the price is insane. A used one would cost me around $700 minimum and I would have to pay shipping from US and import taxes etc. on top, so that's not an option for now.

Hope I can figure out how to set up one of those evaluation boards. Being the noob I am, I have no clue about how to figure out the electronic supply. Hey, if anyone here is from Europe and wants to do it for me for a small fee and pack it up into some provisory box that at least doesn't fall apart, hit me up.

 

[Cbdb2]

If the noise is hum you might have a ground loop. How did you wire up the interconect? Is it rca to xlr? Did you connect the ground of the rca to the - of the xlr?

 

[kartoffelmann]

I'm not sure tbh. I used an RCA to TRS adapter that just gets plugged onto the front. It's a mono TRS basically.

 

[Cbdb2]

Is the rca sleeve ( ground) coneccted to the 1/4 inch ring, sleeve or both? If its wired wrong you might get more noise and less gain.

 

[Cbdb2]

http://www.douglas-self.com/ampins/balanced/balanced.htm#6

Go to section 4 to see how your cable should be wired

 

[JohnYang1997]

Come on. Boosting level is amplifying. You can get as low as noise of an amplifier you want but the source's noise will be amplified. If you only want a compatible level, you don't need to do anything. It's already compatible.