AudioAficionado.org - MDA1000 back in the house...and another on the way

After 15 weeks and 2 days, on Wednesday I picked up my beloved MDA1000 from the repair shop, fully repaired and functioning perfectly, as far as I can tell. Whew...finally!

There were many twists and turns, from attempting to find a new main board (and finding out we couldn't) to replacing a number of components to no avail, to ordering 4 replacement Burr-Brown DAC chips for the left channel from China (used, as the PCM1704 chips are obsolete and unavailable) only to find that this (apparently) didn't solve the problem either. Then we were back to once again trying to procure a replacement board, without success.

Meanwhile, I visited the Binghamton/Vestal area partially on work business, with a few vacation days thrown in. While there, I paid my usual visit to Audio Classics, and discussed my problem with Ryan. He had one MDA1000 in the store, a little dusty but in otherwise very good condition (and three years newer than mine per the DOB on the back). He made me a very attractive offer in the event my unit was unrepairable (which appeared increasingly likely). As an escape hatch, I gave him a deposit and returned home. I advised the repair shop that we were, in effect, running out of time trying to repair my unit.

A few days later, I got the call advising that they had found the problem, and the unit was ready to go. Here's what happened. The MDA1000 contains a total of 8 Burr-Brown DAC chips-4 per channel, in a balanced configuration. 2 of the 4 chips in the left channel were bad. We replaced all 4 left channel chips, and the problem remained. Eventually, the reason was discovered. The reason: 2 of the (used) replacement chips were also bad! The tech explained to me how he went about narrowing down which ones were bad and which were good, it was essentially a swapping around of these surface mount devices...first getting the -6db deficiency down to -3db, and finally achieving perfect balance using two original chips, and two of the replacement chips (the two that were good). Finally, success!

This left me with the decision on whether to still go ahead with the purchase of the MDA1000 from AC. After having gone through this, I started to really see the benefit of having a spare. And, the price was really very good. In the end, I come out with two WORKING units for about $4100. That includes the cost of the repair, the purchase of the replacement unit (with shipping) and the $400 I put up for those replacement chips. Today, I will investigate whether I can recoup $200 of that, since 2 of the chips were bad.

My spare MDA1000 should be at my door early to mid-week next week. I really missed my MDA1000 badly...and one listen to it upon its return was a huge affirmation of just why I missed it so much. It is a spectacular component.