Lamm LL2 w/ Pass labs

The LL2 Deluxe's high output impedance into lower frequencies could result in bass roll-off if used with the relatively low input impedance Pass Labs amp.

Read Stereohile's test measurements for the LL2 Deluxe for details.

FWIW, the Lamm L2 Reference is an excellent match with Pass Labs amps because of its low output impedance.

Do you already own the Pass amp?

The Pass IMO is a tad on the dark side.
Underdog (System | Threads | Answers)

Not my XA-60.5. About as transparent (neutral) a solid state amp as I have heard.

IMO.

My point is that I think the Lamm is very dark and syrupy.
Underdog (System | Threads | Answers)

Oh. I would never had gotten that meaning from your post, so thanks for the explanation.

I owned a Lamm LL2 Deluxe. I thought it had absolutely no color of it's own, yet was a chameleon with tube rolling. I would have never characterized the LL2 Deluxe as dark and syrupy, so perhaps the different impressions we have result from the tubes that were installed in the preamps we heard.

The preamp with stock tubes was lacking some top end extension, and the bass was just a touch bloomy. With Mullard Backburn 12AU7 and Mullard Blackburn 6922 tubes, my LL2 Deluxe was controlled and extended from top to bottom with just a slight touch of softening of the highs (which were outstandingly extended and clear). Swapping in Siemens CCA (or any Siemens 6DJ8 variant) upped the neutrality quotient to a crystalline level. I used it with a Moscode 401HR, VAC Phi 110/110, and a few other amps that I had in-house to audition during the course of my time with it.

Interesting how we audio nuts can have such diverse opinions of the same components.

We are all impressed I'm sure. The guy asked for opinions. I gave him mine. At least I am not afraid to have one.
Underdog (System | Threads | Answers)

I've offended you. Sorry. It wasn't intentional.

I was simply trying to understand your point, and I appreciate your explanation.

My suggestion would be to ask Kent English of Pass Labs.
(service@passlabs.com).

Perhaps include the impedance specs of the LL2 preamp that were published in the Stereophile review I linked to above.

Good luck.

At the risk of beating this dead horse, my concern about output impedance was due to Stereophile test measurements which I linked to above. John Aktinson observed:

"The LL2's output impedance was a low 245 ohms in the midrange and treble, this rising to 3.3k ohms at 20Hz."

The rise to 3.3k ohms at 20Hz is the problem area that could cause bass roll-off if used with low input impedance amps.

Atkinson continued to say:

"Provided it is used into high-impedance loads, the Lamm LL2 offers enormous dynamic range. "

So, I just wanted to offer some data for my statements. The LL2 Deluxe might sound exceptional with the Pass Labs, but I would only buy a used LL2 to test the theory. I'd hate to buy a new one only to find it didn't match well, and then lose my shirt upon resale.

06-30-08: Pubul57
A valid concern, I was not aware that the LL2 had such a wide swing in output impedance in the highs.

Actually, it's the lows...20Hz (not 20Khz). Hence, the concerns about bass roll-off.

The MC402 has even lower input impedance than the Pass Labs with specs of 10,000 ohms (unbalanced) and 20,000 ohms (balanced), so I would think if the LL2 Deluxe has potential impedance matching issues with Pass Labs, then it would have more significant issues matching with the MC402.

Atma-Sphere MP-3. Retail for linestage $4550. Retail with phono option. $5150. The MP-1 works very nicely with Pass Labs, so I suspect the MP-3 would as well.

Audio Horizons TP2.1. It has an output impedance of less than 180 ohms. It has a starting retail price of $2095 and increases with options.

Modwright LS 36.5 has an output impedance of 110 ohms. Retails for $4995.

All are conceivably ideal matches for the Pass Labs.

I have heard neither the Audio Horizons TP2.1 nor Modwright LS 36.5 with Pass Labs, so I cannot make a recommendation. I'm only mentioning them as possibilities because of their low output impedance specs.

Shoot, buy the MP-3 with phono before 9/1/08, and it's like getting the phono for free.

Audio Horizons charges $895 for the phono option.

I don't believe the Modwright LS 36.5 has an onboard phono option.

The Modwright LS 36.5 has an ideal output impedance to match the Pass Labs, IMO. That's why I mentioned it as a good match three posts above.

Oh.

The 9.0SE's output impedance is ~600ohms. Pass Labs' single ended input impedance is 20kOhms.

I don't think this is a good fit. You'd want to see an input impedance of 30kOhms or higher.