If the 47k is fixed, you can only ever load your cartridge at ~470 ohms or lower (for a 10x step up). But if input impedance is set at 240k Ohms, the staring point for a 10x SUT is much higher at 2400 Ohms, and can then be adjusted down to taste. 20x SUT would give you a 600 Ohm starting point. Just much more flexible than fixed 47k loading which to my understanding is largely an arbitrary number that isn’t necessarily the best fit for all pickups, MM or MC.
Shannon recognized this and implemented it in the long retired Budgie. It was called Exacta Loading with top mounted dip switches and was indeed effective.
Yeah, it's a real nice unit. I have a SUT and two transimpedance headamps, all with very distinct and wonderful qualities. The Darlington brings some of the best of the SUT(size, image color, spaciousness) with some of the best of the Slagle design(High energy, up front vocals, dynamic drum whacks). Its can't do everything as well as the respective devices. In almost all areas it is good enough, where the others fall short in multiple important categories in comparison. Please remember I am being ultracritical, these are all fabulous devices. The Darlington has such potential to bridge the SS/SUT divide for my 5 ohm cartridge. I love not having to deal with if I set the load correctly. It could really use some more weight or heft to the sound, and be a little quieter. Yet it beats out my Ypsilon SUT on EPTAS for overall enjoyment. I would love to get a two chassis version with an isolated beefed up power supply. After hearing what all Vladimir Lamm extra capacitance and power supply overbuilding did to my LP2, it's clear that it would take this unit to the next level. Even with the same design. That's on my wish list.
We'll get our next MP out the door soon (officially) and then the unit that Jeff is really looking for, targeting official public release at AXPONA 2024. Just because we're adding some great LOMC capability to the MP line doesn't diminish the fact that we're continuing to pursue the highest-end SUTs and current-mode/transimpedance active step-ups. In fact, the HF EQ Trim in the updated MP will usefully pair directly with this other new product, and dates back to our original SU research in 2016 which was J-FET current-mode in. Our new Balanced Supply Generation (BSG) power supply tech which underpins the updated gen of phono products (directionally desired above) will also strongly and efficiently power other new, non-phono, products too.
Damn! Keith and the crew at Darlington Labs have been very very busy! Was wondering if the MP-7B with its added LOMC circuitry and balanced connections on the back panel comes in a larger chassis? Also wondering, at a basic level without all the added Swiss Army knife optimizations new on the MP-7B, is the sound quality comparable or better than the MP-7? Even so, I’m thinking to wait to trade up my beloved SU-7/MP-7 combo for the Apex version after the AXPONA 2024 introduction. Darlington Labs is on a roll!
I still have my fingers cross for a Darlington Labs mini amplifier - small chassis, single input, speaker and sub out, volume control, nothing else, no digital. A boy can dream!
With their track record to date, it's hard to imagine that SQ took even a teensy step backwards. And if there are no sonic improvements at all, the new additions still make for a very compelling package.
We have never attempted to add features to a product when doing so would decrease sonic quality. We only do so when an overarching new development allows us to improve the sonics -- together with -- increasing the user's flexibility. These updated units all remain in our traditional 5-inch wide chassis.
Upgrade prices are about 1/8 way down the FAQ page. Very very generous to current owners. Thanks so much Keith I’ll send mine in once they get caught up
Just got this via email from Keith in response to my question about upgrading an MP7 to MP7B: "Yes to variable gain and loading in the MP7B and yes to an upgrade path for your existing MP7. MP7 - 56 Volt rail, standard power supply rectification tech MP7B - 68 Volt rail, Balanced Supply Generation tech, significantly enhanced power supply regulation (4 levels), somewhat lower LF background noise, LOMC stage built in (gain variable from +35dB to +72dB), user variable resistance, user variable capacitance, user variable LED brightness, optional balanced output capability MP8B - Everything from MP7B above except 70V rails and Dual Mono power supply regulation, precision thin-film resistors used in many critical locations (vs. thick film in the MP7B), etc. We just ordered Qty 30 of the production MP8B board, it now contains a large number of very high precision 0.1% thin-film resistors which weren't previously advertised and is DUAL_MONO in power supply regulation, with a slightly higher overall voltage rail than the MP7B. Regarding turnaround time to an MP8B, we just ordered a whole large order of PCBs for the MP8 and they are expected to arrive in two weeks. If those work OK, and you place an order today for an upgrade, then send us your unit in about one week from now, everything will hopefully match up and you'll receive your unit back in 7 to 10 days from when it leaves your system. $240 to an MP7B $360 to an MP8B"
PLEASE IGNORE THE PREVIOUS POST! Keith read and wanted it edited to read: "MP7 - 56 Volt rail, traditional power supply rectification tech. MP7B - 68 Volt rail, Balanced Supply Generation technology, enhanced power supply regulation (3 stages of pre-regulation) and an enhanced discrete main regulator, slightly lower LF background noise, LOMC stage built in (total gain variable from +35dB to +72dB), optional subsonic filter (6 or 12dB at 16Hz), user variable resistance, user variable capacitance, LF EQ Trim, HF EQ Trim, user variable LED brightness, optional balanced output capability. Refer to individual product page for specifics. MP8B – Includes all features from MP7B and steps up to a 70V rails with Dual Mono power supply regulation, and also upgrades certain critical resistors to precision thin-film resistors. Refer to individual product page for specifics. Turnaround to an MP7B is estimated at 2 to 3, and turnaround to an MP8B is hopefully 3 weeks pending a large resupply of PCBs under way now. Clients can purchase the upgrade to lock in the new PCB and then send their unit into us a bit later so as to minimize downtime."
I’m tickled for DL and I’m tickled with my set up at the moment. MP7 with a Ned Clayton SUT so I’ll wait for the rush to die down but I’ll most definitely be stepping up to MP8b. It’s somewhat of a no brainer for me. Most versatile piece on the market as far as I can tell.
@krichard2496 I just placed an order for the MP-7b. Can you explain how to use the LF EQ Trim (+0.5dB and +1.0dB at 20Hz, shelving response) HF EQ Trim (-4dB to +4dB at 20kHz in shelving response, with many intermediate steps) And what it's for? Thanks
