Good question but I concluded it was the new. speakers because the cartridge phonostage combination sounded great when I used the LAMM M1.1 amplifiers with the Magico speakers. It was only after I switched to the SET amplifiers and corner horns did the cartridge output became too much for the system.
The Colibri “Master Signature”
- Thread starter Tango
- Start date
Good question but I concluded it was the new. speakers because the cartridge phonostage combination sounded great when I used the LAMM M1.1 amplifiers with the Magico speakers. It was only after I switched to the SET amplifiers and corner horns did the cartridge output became too much for the system.
Thank you for answering. Unfortunately I am still not understanding -- bit that's okay!
The electronics chain generates total gain of phono stage amplification + line stage amplification + power amp amplification. Was the .75 mV output of the cartridge overloading the MM + SUT input of the Lamm phono stage?
Ron, The total gain of the system with the 0.75 mV output with the super high efficient speakers was simply too much. That was not the case with the Lamm M1.1 plus Magico Q3. I don't know how else to say it. I never tried the MM + SUT input with the 0.75 mV cartridge, only with Jeff's SPU and the 0.30 GC which is what I am now using on the back arm.
Last edited:
The Vitavox speakers have only been tried with the all Lamm chain and after I replaced the M1.1 with the ML2. The 1.1 was never tried with Lamm. The 0.75 was tried with Lamm phono and both Pass and Lamm M1.1 amps with Magico. Then the 0.75 was tried with Lamm ML2 and Vitavox. All Pass gear was sold before the Vitavox speakers arrived. (Same day for the Pass amps, actually, with the new owner picking them up as friends were uncrating the Vitavox)
The 1.1 and 0.75 sounded much better in the old Pass/Magico system. I preferred the 0.75, but he changed the damper/suspension too, maybe even the cantilever. Then the Vitavox came and the 0.75 was too much. I should have tried it in the MM input, but never did. I sent the 0.75 back and got a new magnet and fewer windings, basically a new cartridge. When I heard it, I sent my other one back to also be reduced from 0.75 to 0.25, but it is 0.30. One is GC, the other is MS. They look the same except for the "GC" painted on the wood front. They sound slightly different.
Ok, so this possibly is not a gain issue, it could be an impedance issue. In the MS his impedance drops from 0.39 to 0.13 or so as the output lowers. Western Electrics have regularly used high output MS, and Iirc the vox palladian one was highout too. With GC, he is able to get a lower impedance at a higher output. Audioquattr systematically measured his carts at vdh (since he is a local) and mentioned that to me.
You are describing the cartridge/phono pairing. One cartridge is a MS, the other is a GC. Both sounded good with the Lamm LP2.1 through Pass/Magico when they were 0.75, but not with the ML2/Vitavox. Then when they came back at 0.35 and 0.25, they both sound good with the ML2/Vitavox.
My 0.75 GC initially had a load impedance of 20 ohm to 47 Kohms. Now my 0.35 mV GC has a load impedance of 10 ohm to 47 Kohms.
My 1.1 MS had a load impedance of 10 ohms to 47 Kohms. Now my 0.25 mv MS has a load impedance of 5 ohms to 47 Kohms.
These are AJ's hand written numbers changed on the wood box.
But remember, I had to request a lower output because I wanted more usable adjustment on my preamp volume knob. I suppose I could have also sent my Lamm phono back to be adjusted.
The bottom line is that the higher outputs did not sound as good and did not have the volume adjustment options in my new system. The lower outputs both sound better and work in the system better.
I cannot claim high expertise but I don't think the phonostage is overloaded given that my MS is 1.1mV and I've used it with both the LP2.1 and the LP1. I can run into the MC input of either but get fewer steps on the linestage volume control. I agree with @PeterA's supposition that the sensitivity of the Vitavox (16Ohm 105dB - I mean really) Led to his choice for low output.
What is interesting to me is driving a 0.25mV cartridge with the LP2.1's 60dB of gain.
Or ... as you noted, run through the MM input which bypasses the Jensen transformers and lowers gain by 20dB.
Easy Ron. The M1.1 has 32db gain and the Magico were around 90dB/W. The ML2 has a gain of of 27 dB at 16 ohm but the horn speakers are around 106 dB/W - the overall difference in gain of the two systems was 11dB - a gain factor of 3.5 . As a consequence Peter was running his preamplifier in the new system with a very limited number of useful steps with the higher output cartridge.
Considering Shure data on peak velocity http://pspatialaudio.com/max_velo.htm and the Lamm LP1 data on the Lamm site there is no possibility that Peter vhH's were overloading the Lamm phono stage - THD plus noise decrease with increasing level up to 20mV at 1kHz.
The wording here is extremely awkward, and unless you're using the lower gain MM input, then the Lamm phono input isn't presenting 47k to the cartridge. More like 400R to 470R. The matching of the different VdH impedances you've used to that of the Jensen (I think around 5R) in your Lamm is having an effect on your frequency extremes that is audible. The lower output carts should be a better match and as a result produce flatter response and better sound. You could always add an external Jensen SUT (very inexpensive) with different characteristics, and just run it into the Lamm 47k MM input to then have an alternate MC option matched well to the future carts you'll be acquiring. Maybe mono, etc. Keep in mind you'd also *not* be loading that cart at 47k.
I recalled vdh rates their cartridge at 5.6cm or 5.7cm per second instead of the convention 3.XXcm by some Japanese manufacturers
No change. I am using vdh for my reference. I know how it gain matches my phono. Knowing it rates sensitivity at 5cm per sec I could expect how my new cart which quotes its sensitivity at 1cm per sec match the gain of my phono.
Similar threads
 | Steve Williams Site Founder | Site Owner | Administrator |  | Ron Resnick Site Co-Owner | Administrator |  | Julian (The Fixer) Website Build | Marketing Managersing |