Topic: Sound Devices Pre Amp's Mixer's Vs. Decks

[DATPAT]

Since i'm now hunting for a 552 mixer. I called SD devices to get some more info about the pre's in their units. I spoke with Casey I believe it was. He didn't seem to be their top guy but seemed to know the products. I asked him if the pre's in the 552 were the same as those in the 788 since they seemed to have the same foot print and i have heard that the 788 had different and better pre's than the 744 or 722. He said all of the mixers(and stand alone pre's) have the Lundahl Transforms and are the same pre's. He also mentioned that those in the deck were chip based and that all three decks had the same pre's. It's kind of amusing to hear that since several active tapers have been pawning their v3's and other pre's because the pre's in the 788 were so much better the the 44 or 22? So given this info my question is this do people like the pre's in the decks better than the pre's in the mixers? I believe both to be good although a little different flavor. Casey said he like's the pre's in the decks better because they are cleaner. I assume he means they are more transparent and based on the transformers in the mixer's i'd assume they have a little bottom end coloration? Any input would be great. Thanks.

[bryonsos]

When comparing my LB (transformerless) to the MixPre, same mics etc., I find the MixPre to be much more transparent.

[DigiGal]

I recently picked up a MixPre-D which uses input transformers and I find it to be very transparent.

If you are, however, looking for a model without transformers Sound Devices offers the USB Pre 2.  Which can be operated in standalone mode powered by a 5V USB battery without using a computer. 

There are many tapers using the USB Pre 2 and I debated between the two myself for about a year.  I ultimately decided the MixPre-D fit my needs best, I'm very impressed with it and glad I went with MixPre-D instead.

[StuStu]

It's my understanding that the 788's pre is different than the other 7xxs.

[raoulduke]

http://www.sounddevices.com/notes/recorders/788t-mic-pres

788T Microphone Preamplifiers

The 788T introduces a new microphone preamp and analog-to-digital topology to Sound Devices. This new circuit improves the dynamic range of the microphone inputs beyond the performance of the class-leading 702, 702T, 722 and 744T recorders.

The preamps in the two and four-channel 7-Series (702, 702T, 722, and 744T) use discrete transistors (high-quality, old-school, high-current op-amps). These are great sounding preamps connected to a quality, low-noise analog-to-digital converter chipset. Performance versus power consumption broke new ground when these products were introduced, and have yet to be bested in their class in real-world measurements…until the 788T.

The preamps in the 788T were designed in 2008 with the latest topologies and electronic parts. The 788T mic preamps outperform the preamps on the two and four channel recorders, while drawing less power. The 788T has improved dynamic range, resulting largely from an analog-to-digital converter with several dB more dynamic range. While this A/D chip draws slightly more power than those in the two/four channel 7-Series, the preamp circuitry draws less than the earlier recorders. Additionally, these new preamps are fully digitally controlled. There is no analog audio running through a pot like in the old designs. This gives several benefits, including precise gain matching between channels, more control over the limiter, and a much more dB-linear gain curve. It also provides for hooks to control levels electronically, if required in the future.

Because the 788T has eight microphone preamps, its inputs can draw more overall power than the inputs on the two and four channel recorders. When not using inputs the front-panel gain control can be used to turn individual microphone preamps and A/D circuits off, increasing battery runtime.

No, the 702, 702T, 722, and 744T cannot be upgraded. The 788T is a clean-sheet design with an entirely new analog architecture that is not retrofittable to the smaller recorders.

[DATPAT]

Interesting. Like i said the guy i talked too didn't seem like he was a senior tech. But he said all the 7 series recorders had the same pre's and the mixer's were all the same with the lundahl trani's.

[datbrad]

Another point is the mixers, from the mixpre up to the 552, only have input transformers, with active balanced output stages. This results in a more transparent sound. The MP-1 and MM-1 mono preamps have Lundahl input transformers and SD custom built output transformers.This gives those units a slightly different sonic signature than the balance of their product line.

[George2]

SD552 and older 442 have transformer outputs on their XLRs.