Anyone Compared ARC Ref 75SE and 75 With KT150

Veerapeneni ... before upgrading my Ref 150 to the SE version, I dropped in KT-150 tubes. There was a definite improvement in sound. Smoother, deeper and tighter bass, just better sounding all around. The SE upgrade effected another quantum level of improvement.

It's difficult to quantify such changes, but FWIW, Kal at ARC said that the KT-150s likely accounted for roughly half the improvements; the balance relating the SE circuitry changes. Who am I to quibble?

Veerapaneni ...

The KT150 upgrade was a definite improvement over the stock REF-75 in every respect. You wouldn't want to go back to the KT120's that were originally in the amp.

The SE upgrade is in another world altogether. Its simply an amazing amp. If you can afford to send your amp in to ARC for the SE upgrade, I would highly recommend it.

If I were you, I'd keep your current KT150's for spares and opt to have ARC install their own matched KT150 tubes. The tubes in my SE amp are more stable than were the aftermarket tubes I installed in my original REF-75.

Keep in mind that every piece of equipment, whether new, repaired or upgraded (as your's will be) is given a final listen-to by Warren Gehl at ARC ... and nothing leaves the factory until it passes Warren's muster. Your amp will be totally correct and perfect, including your new tubes before being shipped to you.

Let us know how you make out. You're in for a real shocker ... in a good way.

Hope this helps you out ...

Thanks oregonpapa. I will upgrade to 75se when time permits.

I have the 75 with KT150's at the moment. I will be taking it to my dealers in a couple of weeks, hopefully for an A/B comparison with his demo 75SE. I will report back when I have been.

In answer to Oregonpapa's post, I have had no problems with stability in the 150's I bought myself, no need for rebiasing to date. Incidentally, our local distributor is willing to make the SE upgrade without including the tubes, which he will keep for spares. It makes it a better deal.

Here's an excellent review on the REF-150se with a sidebar on the REF-75se.

http://www.theaudiobeat.com/blog/audio_research_reference_150_se.htm