DBX Expander


I have recently acquired a Teac reel to reel and although it's a great machine, soundwise, it just doesn't measure up to CD or LP's in my system. I have a chance to purchase a DBX sound expander that I'm told greatly enhances the sound of the tape. I have no experience with this box at all. Does anyone have any knowledge of what this does?
markus1299
I totally agree when it comes to dial it in by frequency range, and adjustable independent impact level, and overall output level the 5BX has no equal. The Impact Restoration function is worth the price of the 5BX alone. The other features certainly have their place as well it is a great sounding musical piece of equipment. It also has a very elegant look to it. It's rarity certainly makes it a conversation piece.

I have heard of people using the Quantum or Quantum II to perform similar functions and over larger frequency ranges but I have never tried one myself.
Thanks guys for all the very valuable responses. I have had my A4010 reel to reel completely refurbed and my 3BX series 111 is on it's way so it should be an interesting experience through my Cary Slp05. I'll let ya know what I hear or don't hear
Mar
Since my system is balanced, and I'd like to keep it that way, could I just use one 3BX-DS for each channel? Meaning left is inverting - right is non inverting, then combine them back to XLR? I already use gear (Strain Gauge) that puts out balanced signals over 2 RCA's, and have a custom adaptor that goes from 2 RCA's to XLR.

Frzninvt - is this what you are referring to, or did you mean the signal goes through expansion twice? Please elaborate.
The VCA's in the 3BX-DS are mono triggered so dedicating one each to each channel (L & R) improves imaging, staging and definition. It also gives you the flexibility to adjust the channel expansion independent of one another.

I used 2 male RCA to a single female "Y" adapters (two per unit) giving me a single "mono" input on each unit. One for the left channel and one for the right channel. Not daisy chained. I suppose you could do it with XLR to RCA adapters.

Make sure the rear mounted trim pots for HF & LF transition are set equally on the units. You can tweak them as necessary by watching the front displays so you are getting the same level of expansion out of each unit. Having units close in manufacture dates helps too.

The 3BX-DS can be calibrated and adjusted using the Service Manual. Better capacitors in the power supply improve performance as well.
In the early 70s, I had a small, box-sized dbx unit for a short time, which I never used for tape recording noise reduction, but I discovered through trial and error that it did a fantastic job of cleaning up the distortions and surface noise on 78rpm records in real-time........I do not mean impulse or scratch noise, but rather the annoying distortions caused by having played the records previously with worn needles, as well as the inherent way 78s of the pre-war era basically just sound bad to start with.......It seemed to make those noises disappear, and the music, previously difficult to hear because of the continuous noise, would come through loud and clear, almost like magic...........I would have never believed it if I hadn't heard it for myself..........Unfortunately, I traded it in at my audio dealer for a dbx3bx, expecting it to be a "bigger and better" version of the one I had........Of course, I discovered it was a totally different animal and did not perform the functions of the little box, but I kept it because I enjoyed what it did to improve the dynamic range of LPs and FM broadcasts........I would just like to know if anyone can confirm for me what the model number was, as I cannot remember if it was the 117 or the 119, as I am considering picking one up, since they are very reasonably priced on ebay, and also if anyone can confirm its use for eliminating 78rpm surface noise......Sometimes I think I may have dreamt it because the improvement was so sensational........I mean, it practically made an unlistenable record sound almost brand-new........ Any responses would be appreciated......My email address is......edbeta1@msn.com........Thank you in advance for any help........