Impression 11A in the house

[Lightloopy]

After 22 wonderful years with the SL3 I am settling in with the 11A. I have about 90 hrs on them. Breaking them in has been interesting. TTOCS review of his experience was helpful and right on. Thin sounding midrange w/ zingers at certain frequencies out of the box. Prodigious bass compared to the SL3. They have improved significantly now with a big soundstage but the midrange remains on the dry side.
Interestingly, my 250 W mono amp dropped a tube and I plugged in my 75W stereo tube amp and it played very well with it. This was not the case with the SL3 which showed big differences with amp choice. Relieving the amp of driving the woofers must help significantly but still got to deal with the low impedance issue.
I plan to experiment w/ placement, ,bass settings, room treatments over the next few months. After things are settled in I will try the room correction.
Looking forward to hearing these speakers blossom!

 

[ttocs]

I figured the woofers had run in enough when there was around 50 hours on the speakers so I ran ARC and it was a big improvement. Ran it again once the speakers had settled in quite a bit and there was more improvement.

The bass settings do more than you might think. Subtle usage is what worked for mine. I'll lookup the info Martin Logan sent me about the controls and "what" is altered and get those posted. That info really should be included in the manual so we know what we're altering so we have a better chance of getting it right sooner.

 

[twich54]

Congrats on the 11a's, did you get them from Overture ? keep us up to date as you fine tune them

 

[Lightloopy]

I saw the information that you posted from Martin Logan re the bass controls. I don't have the ARC equipment yet but hope to do that soon.
Thanks Dave. Yes, got them at Overture where I got the SL3. Joe J has always been helpful through the years.
Yesterday I stopped by my friend who bought my SL3's. He thinks it's the best speaker he ever heard and enjoying them immensely. I have to agree , they are sweet. The 11's are a different game altogether and look forward to how they evolve.

 

[Robert D]

Congrats on the 11a's, did you get them from Overture ? keep us up to date as you fine tune them

Does the buyer still get a full warranty through Martin Logan when buying from Overture?

 

[Lightloopy]

Overture is a listed authorized Masterpiece dealer on the ML site. I've registered them on the site but hang on to your receipt.

 

[liffy99]

After 22 wonderful years with the SL3 I am settling in with the 11A. I have about 90 hrs on them. Breaking them in has been interesting. TTOCS review of his experience was helpful and right on. Thin sounding midrange w/ zingers at certain frequencies out of the box. Prodigious bass compared to the SL3. They have improved significantly now with a big soundstage but the midrange remains on the dry side.
Interestingly, my 250 W mono amp dropped a tube and I plugged in my 75W stereo tube amp and it played very well with it. This was not the case with the SL3 which showed big differences with amp choice. Relieving the amp of driving the woofers must help significantly but still got to deal with the low impedance issue.
I plan to experiment w/ placement, ,bass settings, room treatments over the next few months. After things are settled in I will try the room correction.
Looking forward to hearing these speakers blossom!

 

[liffy99]

Forgive my ignorance but how is the amp ‘relieved’ of driving the low frequencies ?
Isn’t the speaker crossover fed with a full range signal at power amp level ( not line level). So the amp is still pushing out bass frequencies which are then filtered out in the speaker crossover.
Or am I missing someth8ng ?

 

[twich54]

Forgive my ignorance but how is the amp ‘relieved’ of driving the low frequencies ?
Isn’t the speaker crossover fed with a full range signal at power amp level ( not line level). So the amp is still pushing out bass frequencies which are then filtered out in the speaker crossover.
Or am I missing someth8ng ?

the bass drivers are powered from within by Class D amps

 

[Russr]

the bass drivers are powered from within by Class D amps

Agreed, but isn't the amp still presented with a "load" at those frequencies?

 

[twich54]

Agreed, but isn't the amp still presented with a "load" at those frequencies?

No, the external amp provides the 'signal' to which the internal amp then 'drives' the woofer(s)

 

[Russr]

No, the external amp provides the 'signal' to which the internal amp then 'drives' the woofer(s)

I get that, but the external amp is not going to see an open- or short-circuit at the lower frequencies... I'm assuming there is a crossover that presents the equivalent of the speaker's nominal impedance as a resistive load...?

 

[ttocs]

I get that, but the external amp is not going to see an open- or short-circuit at the lower frequencies... I'm assuming there is a crossover that presents the equivalent of the speaker's nominal impedance as a resistive load...?

Well, what about subwoofers with Speaker Level Inputs? I believe that it's the same situation.

The amplifier for the speaker isn't also driving the subwoofer. It somehow turns into just a signal going to the subwoofer and not the subwoofer showing up as a load to the speaker amp.

 

[gvera]

This is the Montis impedance (solid) and phase (dotted) measurements as per Stereophile. I assume the 11s should measure similar.
As you can see impedance goes up at lower frecuencies, the amp will not need to deliver high current at low frequencies

 

[ttocs]

This is what I got when I did a bunch of measurements to create an Impedance Plot for one of my 13A speakers. Looks pretty similar except for the 3K bump.

 

[denali]

I have a pair of 13a’s and asked ML the following questions:

Question 1

Before the signal is sent to the DSP preamp it is at a “speaker level”, of several volts coming from my power amp. Therefore, the speaker level signal needs to be reduced to “line level” to not overdrive the DSP preamp. This is done by feeding the bass signal into load resistors to get the signal down to line level. So, in effect part of my power amps output below 300 Hz is just being dissipated into load resistors. Is this correct?

ML reply

The signal is reduced using standard SMD resistors. The resistance values are high (over 5000 ohms) so very little power is dissipated.

Question 2

What is the digital resolution of the DSP based preamplifier? Is it 24/96, 24/192 or something else?

ML reply

The DSP runs at 24bit 48kHz. The DSP only handles woofer signals, so higher sample rates are not helpful.

Perhaps JonFo could chime in here as he is extremely knowledgeable about all things ML

 

[ttocs]

@denali that is very good info to have from ML, thank you!