It was a fun experiment. Now I've managed to get resistance, impedance and inductance confused. But I got it now.

The reason for the passive attenuator box was not to attenuate, but rather to allow me to go TRS into the FP10's INSTRUMENT jack. They have a 1Meg ohm input impedance. I did some test recordings and liked the way it made my SM57 sound - better quality high-end. My ribbon though got too boomy.

So, can I just make a xformer box? XLR IN ---> xformer ---> XLR out? Run the shield straight across bypassing the xformer so it will pass phantom power? My Nady RSM4 ribbon has no xformer in it. It's basically a loop wiht a ribbon motor in it.

What xformer? What ratio?

EDIT: I'm discussing two things at once - let me clarify.

I've abandoned the DI box and the 1 Meg ohm load idea. My idea now is simply a xformer box for my ribbon mic. I want a dedicated piece of hardware to compliment my voice. My voice is full and rich but I sing hissy and spitty. Of course I use a pop-filter anyway. The ribbon flatters my lead vocals already, just looking for "more magic". I usually track my backing vocals with the SM57 or my condenser if I need a bright sound.

There's no real problem in making a transformer box given a suitable transformer. You would need to connect the shield across (interconnecting pin 1s on the XLR input and output) so that you have a ground connection but do not connect phantom power to an unbuffered ribbon microphone.

However, what would you hope to gain from using a transformer input? It will not turn an FP10 pre-amp into an API3124+ or a Neumann V476B.

If you look at the [[url=http://[/URL]="http://www.jensen-t…"]Jensen input transformers[/]="http://www.jensen-t…"]Jensen input transformers[/] web page, you will see that the maximum ratio they make is 1:10 due to high-frequency fall-off with ratios much higher than this. A 1:10 transformer will give you 10 times the signal voltage output from your ribbon, but a 30 Ohm mic will appear as a 3KOhm source to the pre-amp. In impedance terms, this would be too high for a standard mic input but OK for a pre-amp DI input, although no guarantee that it would sound anything special.

So I'd have to build a preamp anyway to get any real use out of the xformer, because it would need to drive the xformer and match the impedances. Aww, crap. Better save my money for a Focusrite.

No, not at all, if what you want to experience is the difference in sonic qualities between using the standard microphone inputs versus a DI input via a microphone transformer. The DI inputs of the FP10 (front panel TRS jacks on chans 1 and 2) are only 5dB less sensitive than the microphone inputs, so you should not have any signal level problems.

There is no impedance problem as the DI input is 1 MOhm, but a further experiment would be to wire a 100 KOhm variable resistor across the transformer output (DI input) and listen to what happens to the vocal quality as you change the effective input impedance of the pre-amp from around 90K down to a few KOhm.

I see. Variable impedance and xformer sound. So this box would be a few connectors, xformer, and a pot. I can do that.

Actually, the Jensen transformers for microphones are available in 1:6, 1:10 & 1:15. The JE 115 versions are what are now being used in API 512/312 preamps where they used to use the 110 version before. And Jensen's own 990 op amp that he designed utilizes the 1:6 transformer. And yes, utilizing an actual microphone input transformer to the direct input of your FP 10 should work amazingly well. Having the potentiometer across the secondary will give you the ability to have variable impedance. You will discover not only changes in level but in the tonality/response. There are as many crappy microphone transformers out there as there are good ones. The older ones (Beyer/UTC/Triad/customs by console manufacturers) many people pooh-pooh over the Jensen/St. Ives/Marinair types. But those earlier ones plenty of hits were recorded with so only you can be the judge. I have 20 API's with both Jensen's, Beyer & original API transformers and they all sound fabulous and most folks (except for some folks like us) can't tell the difference of what they're listening to. They can only tell the difference when they look at the specification sheet and test data. That's important if you listen with your eyes. You really don't want to use that attenuator box either. If you need phantom power for a microphone (which you don't seem to need) you need to purchase an outboard phantom power unit. But you don't need that what the 57 which can live through that and you absolutely don't want that for a ribbon of any kind unless it specifies it's necessary (i.e. active ribbon microphone). A ribbon microphone without an internal transformer is simply a micro amperage fuse which will generally blow up as soon as you plug it into Phantom power. So just get yourself some of those transformers and make sure you don't wire it up backwards again. The microphone goes into the low impedance side and the high impedance side goes into your DI input. The direct box works backward. So basically with the direct box all you need is an XLR female to female gender changer (such as a rewired microphone cable as opposed to an XLR barrel). So try the direct box again and take the 1/4 inch inputs of the direct box and utilize those as the output (Only one is required you don't need to loop through) to the DI input. Then let us know how it sounds?

Ear on Rear
Mx. Remy Ann David

Thanks! I'll give this a try tomorrow.

From my research and also looking at the your budget, i would probably go a bit higher in price and get a Golden Age Pre-73. Why? Well, because if you do not like its stock sound, then you can def invest into modding it. They are $375

People also swear by the M-Audio DMP3 for a nice clean sound with minimal coloration. Also, the Studio Projects VTB-1

I am pretty sure all 3 of the above will fit your needs as a starter.

Focusrite also has really nice preamps that come in their Scarlett series. Maybe not the Liquids but...they do sound better than most stock preamps in interfaces in its price range.

I know someone said something about Focusrite being "pretty" but...hey....there are too many reviews out there that say the stock preamps in the Focusrite are the ticket to starters.

assemblethelight, post: 379233 wrote: From my research and also looking at the your budget, i would probably go a bit higher in price and get a Golden Age Pre-73. Why? Well, because if you do not like its stock sound, then you can def invest into modding it. They are $375

My bro just picked up the GAP73 a couple of weeks ago. He sent me some audio samples for me to blind listen compared to his old Mackie mixer. Needless to say there was no contest. The GAP73 is a sweet sounding preamp. It really has a way of toning down the highs. Of course this was an unfair comparison but I can tell you that you would be hard pressed to find a stock preamp in any of the mid range and probably some of the high end audio interfaces that could come close. For the price, it's an incredible bargain.