[SteveFord]

Amp is percolating, VTLs are MB250s with Winged C power tubes and yes, I will try this with the MMGs.
I think it will work out really well with that system as it's kind of dark sounding compared to the 1.7 set up.
Even with all of the tubes in it the Sonic Frontier gear sounds like a (really good) SS preamp so it really needs a tube amp to keep from making your ears shrivel up and fall off.
Some of the mushier SS amps have worked out well with the 1.7 system but then you lose all of the detail that this Crown brings out. 
I'll fool around with this amp some more tomorrow.

I need an inexpensive, temporary amp for the 1.7 system and I was hoping that this would be it.  I'll bet a tube buffer would take the edge off but I don't see a way to insert one in between the amp and the SFL-2. 
It's always something.

[OzarkTom]

I need an inexpensive, temporary amp for the 1.7 system and I was hoping that this would be it.  I'll bet a tube buffer would take the edge off but I don't see a way to insert one in between the amp and the SFL-2. 
It's always something.

Changing the stock binding posts also takes some of that edge away.

[rollo]

    Gentleman please be advised that all class "D" amps perform their best after being on and connected for 24Hrs minimum. The power supply likes being on a while.
    It would be advisable not to be critical until the amp and cables settle. Most likely the reason we hear the words fatiguing and edge. I would recco that the unit is plugged in for at least 24 hours before any critique.


charles

[steve f]

I've been working on a difficult loudspeaker design, and I'm using two XLS 1500s for a lot of the early listening tests. Being able to dial in crossovers digitally is a nice plus too.

( I like to consider a concept, try a few drivers on hand, or order a couple of drivers and work around them. The process is rather intuitive at this point. After I have a basic premise, I start measurements, and go on from there. Then I work on appearance. After that, the design gets tweaked again. Works for me.)

I am surprised at how good the Class D amps sound. They've  been on 24/7 for a couple of weeks. They have  kicked a couple of well regarded tube and solid state amps to the curb. I never bought into the idea of keeping amps on continuously. I have to eat my words on this one. I'm in agreement with rollo.

steve

[mjosef]

I need an inexpensive, temporary amp for the 1.7 system and I was hoping that this would be it.

It could very well be...but you will never know by using the RCA in and those banana-speaker-posts out.
XLR-in and SpeakOn-out offered a much improved sound vs what most people on tour and current owners seem content to default to.  At least use an RCA to XLR adapter, and 'observe' for oneself. With the last amp tour (NCores) a RCA-XLR adapter was included which was quite a good one.

[OzarkTom]

Pomona binding posts with spades or bananas makes an excellent choice also. Then cryo the amp and it becomes much better. Those  two tweeks costs 75 bucks more. So that will cost a total of $275  or less if you buy it used.

[roscoeiii]

It could very well be...but you will never know by using the RCA in and those banana-speaker-posts out.
XLR-in and SpeakOn-out offered a much improved sound vs what most people on tour and current owners seem content to default to.  At least use an RCA to XLR adapter, and 'observe' for oneself. With the last amp tour (NCores) a RCA-XLR adapter was include d which was quite a good one.

Hmmm, rca to xlr adapters eh?

[mjosef]

Yeah, I think the NCore tour one was about $10.

The only time I can recall the sound being anything close to 'edgy' may have been just after power on...after an hour or so it began to gel.

[roscoeiii]

I need an inexpensive, temporary amp for the 1.7 system and I was hoping that this would be it.  I'll bet a tube buffer would take the edge off but I don't see a way to insert one in between the amp and the SFL-2. 
It's always something.

I use an iTube in buffer mode with 6 dB gain for just thus reason. And the hotter signal to the XLS also seems to benefit the sound.

Just pop it between the XLS and Sonic Frontiers

[earsfirst]

It could very well be...but you will never know by using the RCA in and those banana-speaker-posts out.
XLR-in and SpeakOn-out offered a much improved sound vs what most people on tour and current owners seem content to default to.  At least use an RCA to XLR adapter, and 'observe' for oneself. With the last amp tour (NCores) a RCA-XLR adapter was included which was quite a good one.

Hmmm, rca to xlr adapters eh?

Would you call this a good one? Does it have the right wiring?

Neutrik 3-Pole XLR Male to RCA Female Adapter  $8.99
http://www.bhphotovideo.com/c/product/1026927-REG/neutrik_na2mpmf_3_pole_xlr_male_to.html/prm/alsVwDtl

Pin 1 and 3: connected to ground
Pin 2: signal 

[OzarkTom]

Hmmm, rca to xlr adapters eh?


Would you call this a good one? Does it have the right wiring?

Neutrik 3-Pole XLR Male to RCA Female Adapter  $8.99
http://www.bhphotovideo.com/c/product/1026927-REG/neutrik_na2mpmf_3_pole_xlr_male_to.html/prm/alsVwDtl

Pin 1 and 3: connected to ground
Pin 2: signal

Those look very similar to the ones that were on the Ncore tour amps. I may order two of those and send them off with the Salis Audio amp to get cryo'd.

[mjosef]

Those will work alright, dunno about the SQ, the tour ones were black with gold contacts.
Maybe someone will comb through the 30+ pages of the Ncore Listening impressions thread and find the actual ones or the owner of them will stop by here and reveal the source.
Whatever whichever they were they were darn good quality...I couldn't tell the difference with them in-line(with RCA/RCA cable) vs. an actual RCA to XLR cable (both made with same cable).

[OzarkTom]

Those will work alright, dunno about the SQ, the tour ones were black with gold contacts.
Maybe someone will comb through the 30+ pages of the Ncore Listening impressions thread and find the actual ones or the owner of them will stop by here and reveal the source.
Whatever whichever they were they were darn good quality...I couldn't tell the difference with them in-line(with RCA/RCA cable) vs. an actual RCA to XLR cable (both made with same cable).

At my place and my buddy Rex's, the XLRs were quite a bit better than with the adapters to RCA on the Ncores.

[jk@home]

Yeah, usually when one adds extra adapters / connections in a system, it affects the resolution in a bad way.

For giggles and kicks, I had tried going single ended from my preamp, into a high quality Jensen Isomax converting tranny, to the Crown's balanced connections, but found just going from the pre's xlrs (with the converting op amps inside doing the work) sounded better. Probably because of less connections and cables involved.

Also have to say, Magnepans can be pretty finicky with different amp setups. The other pro amps I have (Mackies and Yamahas), didn't sound that good on my MMGs. The Mackies, which were the worst sounding on the Maggies, do just fine in the HT system driving Paradigm Studios.

That said, comparing this $350 amp to high end audiophile amps is interesting reading, but really does the audio cheapskate little good. You know, the guys who have to buy this amp cause of their budget. I would love to see more comparisons with amps like Class D Audio and Emotiva, and other amps in close to the same or slightly more price range.

[SteveFord]

It's better than the Class D amp by a wide margin.  I had one of them here for a visit on the same system and it was kind of lackluster so I was glad that I didn't get caught up in all of the fervor of the Class D thread.
I have no experience with Emotiva gear so can't comment on that one.

[mjosef]

At my place and my buddy Rex's, the XLRs were quite a bit better than with the adapters to RCA on the Ncores.

Was it the same adapters I am talking about?
As in audio there will always be differing opinions/impressions.  Just like your impressions of the Ncores at your place and now vs. the XLS. WHat one man leans to another may lean away from.
And who is this REX you constantly invoke? I had a dog named Rex once. Not that I am associating your friend with same. But you keep reciting his name so the mind goes there. Apologies if offended

[mjosef]

I would love to see more comparisons with amps like Class D Audio and Emotiva, and other amps in close to the same or slightly more price range.

Guess you missed my take on the Class D Audio vs XLS...made the Class D Audio sound like a curtain was over the sound.

Opps, I see Steve Ford heard what I heard. lol

[jk@home]

Guess you missed my take on the Class D Audio vs XLS...made the Class D Audio sound like a curtain was over the sound.

Opps, I see Steve Ford heard what I heard. lol

Thanks, I had seriously entertained the Class D audio stuff, even corresponded with the man.

Got the Pomonas installed yesterday, easy mod. Hopefully today the mail will deliver the new spades I need to get things going again.

[OzarkTom]

Was it the same adapters I am talking about?
As in audio there will always be differing opinions/impressions.  Just like your impressions of the Ncores at your place and now vs. the XLS. WHat one man leans to another may lean away from.
And who is this REX you constantly invoke? I had a dog named Rex once. Not that I am associating your friend with same. But you keep reciting his name so the mind goes there. Apologies if offended

Yes, those were the same since we heard the tour amps here and at Rex's. I have known Rex since 1981 and he is no dog. He probably has owned more systems than anyone else here on AC. He is very passionate about audio, and loves to try various components. He is tailspinrex here on AC but never posts. I talk to him 3-4 times a week, he is truly a great friend even if he was not an audio buddy.

I see used Ncores up for sale here on AC and Audiogon all the time, so Rex and I aren't the only ones that did not like them. There were plenty of others on the Ncore tour that did not also.

[SteveFord]

The great 1.7 test continues.
Amp left on for 24 hours.

Plugged directly into the wall: smoother sounding but it lost the "sharpness" to the sound, seems to be some loss of detail compared to being plugged into the APC
XLR to RCA adaptors, plugged into wall - knocked off some more of the details and highs
XLR to RCA adaptors, plugged into power conditioner - brought back some of the details and highs
Plugged into APC, RCA to RCA - best of the bunch.
If there was any difference in never turning this amp off it's subtle, at least in my house.

All variations done with the Supra LoRad power cord instead of the supplied one.

Conclusion: it's a forward sounding amplifier which is not surprising as it's made for PA gear and the Sonic Frontiers is a forward sounding preamplifier so it's not the ideal pairing. 
For what it's worth, the solid state amps that worked best with this system were a refurbished Carver and a refurbished Harman Kardon Citation.  Neither one had the resolution of this Crown but the sound was smoother so there was no listener fatigue.
3.7s and MMGs coming up next.