Orchard Audio GaN 150W monoblock amplifier

[davide256]

As a long time Magnepan owner, amplifiers have always been a challenge for me. Maggies are wonderfully transparent speakers but with their 2 ohm impedance in the treble

and their "door" size panel drivers they have always been a challenge to drive well through the entire audio spectrum. Conventional wisdom has always been buy the biggest amp

possible but cost and heat output have deterred me from that path.

 

Over time I've used the following

Bryston B60r... flawless but no transient excitement, like a high pass filter was always on (60 watts)

Prima Luna Premium integrated with KT150 tubes,  lush but bass was mushy  (~60 watts)

Hafler DH200 with Musical Concepts, plenty of transient excitement, good bass but background instruments were often indistinct ( 100 watts +, not sure how much the mods increased wattage)

 

Not knocking these amps, as with other speakers they will sound different, but they just didn't match well with 1.7 Magnepans.

 

Class D was enticing, a high power solution with low heat but ICE and other original class D designs had a "but" in their review praise, the treble didn't match up to

how well the lower regions performed. So waited until reviews of GaN chip products came out and decided to try the Orchard Audio GaN monoblock amplifiers.

 

Have had them in my system for 2 days now, very happy with results. Have learned that both the Hafler amp and the LTA MZ2 (used as pre) were contributing to

the indistinct character that was bothering me, some sort of low level harmonic fuzz. Am now using a Schiit passive pre to feed the monoblocs.

 

Clarity is excellent, behavior exemplary throughout the audio range.  The difference between a good recording and a so so one now makes me sad, its much bigger,

(more motivation to buy La La Land remasters 😉)

Has me wondering just how much better things will get if I can get the RCA to XLR converters out of the signal path.

 

For $1599, I'm well content

 

 

 

[davide256]

picture of amps. The speaker wires I have used horseshoe spades, these just barely fit through the openings in the plastic surround for the speaker terminals.

 

 

[Rexp]

On 4/10/2022 at 11:49 PM, davide256 said:

As a long time Magnepan owner, amplifiers have always been a challenge for me. Maggies are wonderfully transparent speakers but with their 2 ohm impedance in the treble

and their "door" size panel drivers they have always been a challenge to drive well through the entire audio spectrum. Conventional wisdom has always been buy the biggest amp

possible but cost and heat output have deterred me from that path.

 

Over time I've used the following

Bryston B60r... flawless but no transient excitement, like a high pass filter was always on (60 watts)

Prima Luna Premium integrated with KT150 tubes,  lush but bass was mushy  (~60 watts)

Hafler DH200 with Musical Concepts, plenty of transient excitement, good bass but background instruments were often indistinct ( 100 watts +, not sure how much the mods increased wattage)

 

Not knocking these amps, as with other speakers they will sound different, but they just didn't match well with 1.7 Magnepans.

 

Class D was enticing, a high power solution with low heat but ICE and other original class D designs had a "but" in their review praise, the treble didn't match up to

how well the lower regions performed. So waited until reviews of GaN chip products came out and decided to try the Orchard Audio GaN monoblock amplifiers.

 

Have had them in my system for 2 days now, very happy with results. Have learned that both the Hafler amp and the LTA MZ2 (used as pre) were contributing to

the indistinct character that was bothering me, some sort of low level harmonic fuzz. Am now using a Schiit passive pre to feed the monoblocs.

 

Clarity is excellent, behavior exemplary throughout the audio range.  The difference between a good recording and a so so one now makes me sad, its much bigger,

(more motivation to buy La La Land remasters 😉)

Has me wondering just how much better things will get if I can get the RCA to XLR converters out of the signal path.

 

For $1599, I'm well content

 

 

 

I wouldn't worry too much about rca to xlr, you do need a better pre amp though...

[davide256]

12 hours ago, Rexp said:

I wouldn't worry too much about rca to xlr, you do need a better pre amp though...

Looking into that, may go for a Freya S. Need to learn more about best design practices for RCA to XLR conversion first.

[botrytis]

Well, the Benchmark AHB2 has instructions to use single-ended to RCA, and it has a sensitivity setting, which need to be set at 2 VRMS or 4 VRMS for RCA input. if not, you will have way lower volume on an amp with only balanced input.

[DuckToller]

 

26 minutes ago, botrytis said:

Well, the Benchmark AHB2 has instructions to use single-ended to RCA, and it has a sensitivity setting, which need to be set at 2 VRMS or 4 VRMS for RCA input. if not, you will have way lower volume on an amp with only balanced input.

+1
The manual of the OKTO DAC Pro does as well tell us that unbalanced to balanced connections may harm their device, if not properly grounded:
"Warning: we discourage from using balanced-to-unbalanced cables and converters. Doing so will result in a vastly decreased analog performance and may be also cause of groundloop induced hum issues. Unbalanced signal paths (e.g. widespread RCA) are unsuitable for
device-to-device connections if high signal performance is desired, since they do not offer a separate path for equalizing ground loop currents that will naturally occur in a real-world environment. Additionally, XLR to RCA cables or converters commonly have XLR pin 3
shorted to ground, which will overload the dac8 PRO’s output stage and may even be cause to damage after long-term use with high signal levels. In case you need to interface the dac8 PRO to an amplifier with single-ended inputs only, please use cables without the short,
like “Benchmark XLRF to RCA adapter cable for analog audio – pin 3 floating”.
 

[botrytis]

Hence, why I went to all balanced - from my TEAC UD-501 (unique in that it has 2 settings for XLR, the older version and the now std version), to my RC-1590 pre to the Benchmark.

[davide256]

1 hour ago, botrytis said:

Hence, why I went to all balanced - from my TEAC UD-501 (unique in that it has 2 settings for XLR, the older version and the now std version), to my RC-1590 pre to the Benchmark.

From what I’ve read the voltage output of XLR is twice that of RCA. I would expect any pre to take that into account in converting an RCA input to XLR output. And the pre providing a true XLR output should eliminate wired RCA to XLR converter concerns. No interest in being confined to XLR source output solutions given all the legacy RCA devices

[botrytis]

1 hour ago, davide256 said:

From what I’ve read the voltage output of XLR is twice that of RCA. I would expect any pre to take that into account in converting an RCA input to XLR output. And the pre providing a true XLR output should eliminate wired RCA to XLR converter concerns. No interest in being confined to XLR source output solutions given all the legacy RCA devices

According to Benchmark, no. I asked them before I bought it. There would have to a some way to vary the pre output and there is not. SO, I would not assume that. That is why many amps have variable inputs.

[davide256]

Soo, still enjoying the GaN monoblocks but its forcing me to make some changes. Notably the top end sounded "hot" in my system with no changes from how

it was optimized for the Hafler DH200. Notably the upper treble region from the Metrum Octave DAC/SRC-DX DDC combination made me feel like my speakers

had been swapped for Koss 1-A electrostats, mercilessly aggressive. So a caution if you buy this amp, combine it with a DAC/DDC solution that has well behaved upper treble. Switching the DAC to Chord Mojo helped somewhat and changing the DDC to a Schiit Eitr seems to have this tamed

[davide256]

Suspecting now that the Orchard Audio amp isn't as well behaved with 2 ohm loads as the Hafler... Magnepan 1.7's drop to 2 ohms at 10K.

Inserting the "comes with" 1 ohm resistor into treble attenuation jacks in the past didn't mitigate bright/edgy source electronics but  in this case

it did smooth out the treble aggressiveness, presumably because the amp now sees a 3 ohm load in the treble. Reached this conclusion after

comparing same recordings on vinyl and having the same problem with aggressive treble.

[davide256]

On 5/25/2022 at 12:24 PM, davide256 said:

Suspecting now that the Orchard Audio amp isn't as well behaved with 2 ohm loads as the Hafler... Magnepan 1.7's drop to 2 ohms at 10K.

Inserting the "comes with" 1 ohm resistor into treble attenuation jacks in the past didn't mitigate bright/edgy source electronics but  in this case

it did smooth out the treble aggressiveness, presumably because the amp now sees a 3 ohm load in the treble. Reached this conclusion after

comparing same recordings on vinyl and having the same problem with aggressive treble.

Ordered some 0.5 ohm 12 watt Mills resistors, want to see if  I can fine tune this a little better, ie bump  the speaker resistance to 2.5 vs 3 ohms and still lose

the harshness

 

https://www.parts-express.com/Mills-0.5-Ohm-12W-Non-Inductive-Resistor-005-.5

[davide256]

Back to no resistor, listening showed that I was losing high frequency xylophone strikes.

 

@Rexp I get your comment about the TAS reviewer using single ended tube pre's now. My gut suspicion is that

the Orchard Audio GaN amplifiers will easily pass along/accentuate odd order harmonics in the treble and that a tube

pre attenuates these

[Rexp]

2 hours ago, davide256 said:

Back to no resistor, listening showed that I was losing high frequency xylophone strikes.

 

@Rexp I get your comment about the TAS reviewer using single ended tube pre's now. My gut suspicion is that

the Orchard Audio GaN amplifiers will easily pass along/accentuate odd order harmonics in the treble and that a tube

pre attenuates these

So you going back to class A, A/B? We have enough distortion to contend with, without worrying about power amps.

[davide256]

22 minutes ago, Rexp said:

So you going back to class A, A/B? We have enough distortion to contend with, without worrying about power amps.

Unlikely. The net sonic gains far out weigh the treble challenges, better the class A/B amps I've had and now thats its summer, I really appreciate

the low heat output. Will try treble taming strategies like a shibata stylus cartridge (Hana SL) and better behaved DAC as these were on my roadmap

anyway.

 

[davide256]

@RexpOk. So I went back and used the LTA MZ2 as 1 watt amp... and it looks like I'll be selling the mono blocks. With the LTA as amp I can relax and enjoy the music,.

may not be perfect but it is fluid and relaxed vs precise and edgy. Back to square 1 for a next amp

[fas42]

Have you tried Sanders' Magtech units? Specifically engineered for these sort of drivers ... I heard these driving low end Magnepan speakers at the last audio show, and when sourced from a non-distorting front end, I couldn't pick any faults with what they were doing.

[davide256]

So.. after listening with the LTA MZ2 for a few days, I've realized that the GaN mono blocks emphasized something that I couldn't un-hear,

a low level treble harmonic break up that the MZ2 as amp diluted but didn't eliminate. It was a problem that was particularly nauseous

 with massed treble strings... "elevator" music became a house of horror, not relaxing.

 

I'm working through changes to improve, swapping coax cable, switching to UPNP vs Stylus for endpoint protocol. Have gotten to the point where

I've pulled the LTA MZ2 out as pre ( loss of upper and lower end detail) and put the passive Schiit SYS back in;

things aren't perfect yet but I can see daylight at the end of the tunnel, music with "1000 and 1 strings" is clean.

 

Continuing on with the GaN experiment...

[davide256]

Things have gotten quite a bit better but it took some fiddling to get there. 
1- Metrum Octave DAC while nice for midrange detail had issues with treble harmonic irritants, Chord Mojo is cleaner

2- NAS was contributing dissonance in complex instrument passages, switching to USB attached M.2 Intel 660 P greatly improved

3- my coax cable choice mattered, a short RCA to mini RCA ended up cleaner for treble than my “ audiophile” 1 meter coax choices

Have gone back to using the MZ2 as pre, while the mono blocks are more detailed using  passive pre, the trade off for that lovely tube sound is worth it.

 

Overall the GaN monos are sounding lovely now, but continue to prod me to get a better DAC

[Rexp]

Positive review of their stereo amp:

 

https://hometheaterhifi.com/reviews/amplifier/power-amplifier/orchard-audio-starkrimson-stereo-ultra-amplifier-review/

[davide256]

If anyone wants to try this it works really well. Cayin RU6 with 4.4mm balanced to XLR cable into Orchard Audio mono blocks. Cable available on Amazon. Lacks really low bass but above that timbre details just pop

[davide256]

On 6/25/2022 at 11:16 PM, davide256 said:

Things have gotten quite a bit better but it took some fiddling to get there. 
1- Metrum Octave DAC while nice for midrange detail had issues with treble harmonic irritants, Chord Mojo is cleaner

2- NAS was contributing dissonance in complex instrument passages, switching to USB attached M.2 Intel 660 P greatly improved

3- my coax cable choice mattered, a short RCA to mini RCA ended up cleaner for treble than my “ audiophile” 1 meter coax choices

Have gone back to using the MZ2 as pre, while the mono blocks are more detailed using  passive pre, the trade off for that lovely tube sound is worth it.

 

Overall the GaN monos are sounding lovely now, but continue to prod me to get a better DAC

 

 wanted to update this thread in case anyone else who uses Orchard Audio GaN mono blocks reads it.

 

Have determined that Stylus mode in Euphony is largely the cause of problems I've been having with choral, high strings and various sound tracks

sounding irritating, off for harmonic structure. Switching to UPNP mode for Euphony is much better behaved at a slight sacrifice of transient slam.

According to @Miska class D doesn't behave well if fed frequencies above 20k, could be that Stylus doesn't have a good cut off filter

 

With the improvement from UPNP I've gone back to using Pre90 and Chord Mojo as the MZ2  "subtractions" are more noticeable and the Mojo

transient ability is more pleasing