[dougli]

I recently received my Corda HA-1 back from KurtW, who had made his "Corda Blue" mods to it. I am simply amazed at the dramatic improvement. I was expecting good things, having read kelly's Corda HA-1 / Corda Blue comparison. But you know how so often the anticipation of something leads to a letdown when you actually obtain that thing? That most certainly did NOT happen in this case. The Corda Blue mods provide an amazing sound enhancement. Prior to this, I was impressed with the overall sound reproduction of the stock Corda. It certainly is an excellant amp for the money. Now, however, I can hear what was missing. The Corda Blue now exudes deeper, fuller, more impactful bass. The mids are more separated yet cohesive, and the highs are more detailed without harshness. The effects are across the spectrum, resulting in an overall more forward, crisper, richer and authentic sound. Even the silence is more silent. Now, I don't have an array of mid-range and high-end amps to compare to the Corda Blue. But I have heard a few of them, and I suspect that this modified HA-1 may be the least expensive way to obtain audiophile sound (yes, that loaded phrase), while including crossfeed. I would highly recommend these mods to anyone who has, or is considering getting, an HA-1. KurtW has stated that he is willing to take on more conversions. For DIYers, the changes are given in kelly's review.

My before-and-after listening was done through DT931s and HD600s, out of a DVP-NS500V. The changes with the HD600 were especially dramatic. I have even postponed the acquisition of an aftermarket HD600 cable, due to what the Corda Blue has done for these phones.

 

[FCJ]

Quote:

Originally posted by dougli I have even postponed the acquisition of an aftermarket HD600 cable, due to what the Corda Blue has done for these phones.

All right Doug!!!

If I hadn't just bought the KAG K-1000s (and the vinatage Marantz amp to drive them), I would consider the upgrade. The HA-1 sounds great, as is--I can just imagine what the "Blue" improvements sound like.

The Cardas cable upgrade will improve the sound even further, both in high-end extension and a tightening-up of the low end. If anything, it will "improve on the improvements," not take away from them.

 

[FCJ]

Quote:

Originally posted by FCJ All right Doug!!! If I hadn't just bought the KAG K-1000s

That's "AKG" not "KAG." That's what happens when you type too fast. . . .

 

[dstroot]

I also got Kurt's "full monte" treatment on my Corda. I received it a few weeks ago and have been VERY busy since. But I have had a few opportunities to audition it and it's significantly improved.

I was inspired by Kelly and agree with the comments posted in this thread. Note that originally I thought the HD600 and Corda made a poor pairing (I bought both from Jan) . After the HD 600 and the Corda broke in it got better, but the Melos and HD 600 is about as good as it gets (on my budget) with good Amperex tubes.

I heard the Max at the Headroom roadshow as was really impressed, so I asked Kurt to upgrade my Corda and crossed my fingers. Now I'm not saying a Corda Blue is a Max, but the smoothness and punch of the amp now reminds me of the Max - it has that "type" of sound (could be due to the opamp change)

It now pairs great with the HD-600 (I have the Equinox cable on them) and definitely came out as a good or better than expected. Overall I was very happy. I'm not very good at describing sound but I know what I like!

Source: Sony SCD-333ES SACD Player

Other HeadPhone Amps: Melos SHA Gold

Phones Senn HD600, Ety ER4p, Grado SR-325

Kurt also graciously included a song "sampler" CD, which I assumed was copies of the digital photos he took and didn't even listen to it until last weekend. It was awesome! Thanks Kurt.

 

[kelly]

dsroot
dougli

Thanks for posting your impressions. It's good to hear from other people and I'm glad you weren't disappointed.

In a direct AB comparison, I actually found the Corda Blue to be smoother than the Max (as well as, of course, having much better air and ambient detail). The Max is a smooth sounding amplifier, so take this as a compliment to the modded Corda rather than an insult to the Max. It was only in the deep articulate bass and speed where the Max was truly in a class above the Corda Blue. The blackness of the Max is also a bit better still.

If you like the HD600, I agree that the Cardas cable still helps and is probably worth it to you.

From my memory, I think I would also still take the Melos over the Corda Blue with the HD600, but the margin has considerably narrowed post-modification.

 

[Nightfall]

Originally posted by dougli
I recently received my Corda HA-1 back from KurtW, who had made his "Corda Blue" mods to it. I am simply amazed at the dramatic improvement.

I also have a Corda HA-1 and have considered the same modification. Could you tell me what the cost for it was? Also, how long did it take? Thanks.

 

[dougli]

I'd suggest sending a PM to KurtW to inquire into the current cost. My amp was gone for about 12 days from the time I sent it off until I received it back.

 

[KurtW]

Doug and dsroot, thanks for your feedback, I'm glad you were pleased with the results.

I recently have put in a lower current version of the Corda Blue's FET cascode current sources into my Porta Corda. Unlike the standard Corda, the Porta Corda wasn't biased into Class A operation and this is probably one reason why it didn't sound as good. The biggest fault I had found with the Porta Corda was a little harshness in the treble and I think this mod has help a lot in this regard. The only downside is about 15% less battery life, a worthwhile trade off IMO. The integrated circuits that I used in the Corda Blue mods would not work well in a portable application, so adding the current sources was the only thing I changed.