staticV3
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Hi. Are you saying that their MC275 amp from 50 + years ago was better than the MC275 being produced today?MacIntosh as brand is not what it once was ,as so many hifi brands that's just husk of what they really where .
back in the day when they mattered , they where legit .
Heck, the internal amplifier to my 1977 ADVENT 300 beat that! (I only use the ADVENT 300 as a preamp anyway, as the pre-outs run into a pair of NAD 2100's [done by Peter at Quirk Audio in their early days]).This is a review and detailed measurements of the Carver Raven 350 tube monoblock amplifier. It is on kind loan from a member and (I think) costs US $4,750.
View attachment 225095
The 350 is not a bad looking amp. It has the same "orange peel" paint job of the previous Carver 275 amplifier I reviewed. At 42 pounds, the unit is pretty heavy. With all the weight in the back, the front handle is kind of useless when it comes to lifting it.
View attachment 225100
There is an XLR input but I believe it is for convenience and performs the same as RCA. I measured the DC resistance of the 4 and 8 ohm terminals (after the measurements) and realized they are both the same! Here I was switching back and forth between them. Anyway, measured DC resistance is 0.47 ohm. The 1-2 ohm tap has a lower DC resistance of about 0.3 ohm.
Unlike the 275 amplifier, the fuses did not blow and the amp survived my sweep tests. Bias is to be set at "80" on the front dial and that was the case when I powered on the unit.
There is a gain control but you are advised to set it to max which is what I did for testing.
There is a flip switch in the front which changes the amount of feedback. I tested the amp in both settings.
Here are the specs:
View attachment 225121
Carver 350 Measurements
Let's start with high-feedback performance using XLR input:
View attachment 225102
There is copious amount of distortion causing SINAD to be dominated by it. At 44.1, it ranks as the second worst amplifier ever tested:
View attachment 225104
It even performed worse than the Carver 275 which had a SINAD of 46. Switching to lower feedback doesn't make things that much worse:
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Note that gain is reduced and therefore, volume will be different. This makes AB testing tricky. Here is a more detailed FFT showing the small difference between low and high feedback:
View attachment 225115
Notice how distortion is made up of both 2nd and 3rd harmonics so you can't make the argument that it is "2nd harmonic goodness."
As noted, RCA performance is the same as XLR:
View attachment 225107
Power supply 60 Hz noise in both cases causes severe intermodulation higher up in frequency. No amount of grounding impacted that so it is endemic tot he design.
Noise performance is decent for type of amp it is:
View attachment 225108
Intermodulation distortion rears its ugly head again in multitone test:
View attachment 225109
I don't know how anyone could hear more "detail" with such an amp where so much of the music signal will get lost in the distortion "grass."
Frequency response should be flat but it is not:
View attachment 225110
It naturally will have load dependency due to output impedance.
Let's see the power situation as we had serious shortfall in the 275 amp:
View attachment 225111
We don't meet the spec there but come closer with 8 ohm:
View attachment 225112
Back to 4 ohm, here is our 1% THD (double the company spec) max and burst power:
View attachment 225113
We seem to get the same shortfall. There is momentary reservoir though allowing the peak output to shoot way up. This was not always consistent though.
I also tested 2 ohm capability:
View attachment 225114
You are still current limited so no more power.
Changing the test frequency gives us the following power curves:
View attachment 225116
There is some instability at 20 Hz and fairly significant power drop. This points to power supply not having enough capacity as the lower frequency taxes it for longer period. Some drop occurs in every amplifier by the way so it is a matter of how much.
Finally, the amplifier warms up quickly and is pretty stable:
View attachment 225117
Testing occurred after this warm up.
Conclusions
What an upside down the world of audio is. Folks want to pay so much more to get dirtier sound. You want dirty? The Carver 350 gives it to you. Even at 5 watts there is copious amount of harmonic distortion. Power supply mixes with that at such high level that it creates its own spread of distortion. A video must come with these amps that hypnotizes you into thinking you are getting great sound....
I can't recommend the Carver 350 monoblock amplifier.
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it migth be the same amp , I honestly dont know , but they don,t inovate much and create very expensive stuff nowadaysHi. Are you saying that their MC275 amp from 50 + years ago was better than the MC275 being produced today?
I understand, and I don’t know a whole lot about them, even though their headquarters is only an hour away from me. But I see a lot of expensive gear going out their doors, I don’t think the passion is there anymore.it migth be the same amp , I honestly dont know , but they don,t inovate much and create very expensive stuff nowadays
Seems like you are making pretty large assumptions leaps by taking a preamp that Roy Mottram designed and are comparing it to a totally different designed preamp, and then extrapolating that to VTA-70 vs original ST-70, which you have not really studied, let alone heard.Hi, I agree with some of that, but just because someone puts bigger better transformers in, and add some tubes doesn’t mean it’s going to perform any better. As witnessed by the measurements that Amir did, the original ST 70 measured better.
What about my preamp that Bob supposedly turned into a super preamp? Was it necessary? Is it more transparent than mine? Where’s the data to back it up, or is it just part of a sea of online folklore? Here it is in black-and-white, if you’re going to claim bigger better stronger faster show me the specs.
Maybe Bobs preamp measures better than my stock SP-14 but I seriously doubt it, and I seriously doubt it sounds any better. That’s the extent of my knowledge, and does my SP 14 that Roy Mottram built sound any better because I opted for the best capacitors he had to offer, the NOS tubes, The XLR inputs and outputs, and a couple other things that were upgraded? I’ll bet in a double blind test no one was picking mine out over the less expensive version.
Everybody hears differences… When they’re sighted. If you go on Audiogon there is more opinions than there is gear out there, and for the most part it’s all money based… Spend more money get better quality. Untrue, and unless something is engineered properly it could cost $20,000 and sound no better, possibly worse, and possibly measure worse. That’s my two cents, although I get what you’re saying and theoretically it should all work out. Don’t forget that they had tube amps pretty perfected for the most part especially by the 1960s, so decades of design goes out the window with these many of these new pieces in my opinion.
Not to disagree with you entirely, I do get what you’re saying.
yeah, but mine can handle 6 ohm. choose your speakers wisely.An OTL can have quite high output impedance ? so with most speakers the frequency response will be slightly modified , it might possibly be in such way that it's sounds "richer"
Most likely it is not. This is on purpose. Acc. to Bob it is not needed and double insulated.Looks like the neutral pin is not connected to a chassis ground, answering my earlier question. I would not take my chances with this amp.
In before Pace, Rhythm and Timing are mentioned... or am I too late?ASR has the measurements to show us. Who are all of these "Dynaco experts", and what do they have to show us? Or you just talking about someone who has an opinion?
Remember:
View attachment 225657
Jim
In the pre-internet world I once spent a year shopping for a tea kettle. Them's were the days...I agree. I’ve also spent a long time in the dark until sites like this. I’m not an engineer and depended on Hifi shops and magazines for information. Stereophile was all I was using as a source for measurements and they were extremely hard to understand as there was never any context or comparison of the results. Just JA at the ended summing it up with something like “it measures respectably”. With the wealth of information out there now though, I rarely feel too bad for someone not willing to do a little research before making a $9k amp purchase. Hell, I spent 3 days researching the last $200 vacuum I bought. But that’s just me
I don't get it either as I know of Bob's reputation for solid state design, not tubes. When I asked him in person why he is designing tubes, he said because he likes it. And later read him saying that there is a lot less competition with tubes than transistors. The people buying it are seemingly doing so based on his reputation as an audio genius designer. How much he sells, I don't know. He is definitely not in the circle of "high-end" audio buyers.
.... and will prevent earth loop noise.Most likely it is not. This is on purpose. Acc. to Bob it is not needed and double insulated.
My dentist is into tube Schiit gear. Admittedly, he considers himself a bit of an audiophile but when questioned on room modes and adjustments he seemed to draw a blank.
I would love an explanation of how this works...
My point is Bob Latino redid both. So is it possible he made each worse? That’s not a dig on him, but the proof is in the pudding. I will guarantee that there are also many other ST70 fans out there crying… why would you mess with affordable perfection. By all accounts it was already a good amplifier, and it just did what it was supposed to do, amplify a signal.Seems like you are making pretty large assumptions leaps by taking a preamp that Roy Mottram designed and are comparing it to a totally different designed preamp, and then extrapolating that to VTA-70 vs original ST-70, which you have not really studied, let alone heard.
This is not some debated topic in the Dynaco world. Literally, everyone who has had many of the Dynaco derivatives recognizes the substantial superiority of the VTA over the original. Even the few who prefer the original, recognize the better clarity, range, and speed of the VTA- they just prefer the sound they are used to.
This puts us with:
All Dynaco Experts: VTA70 is clearly better
ASR: ST70 is better
There is an explanation for this. I don’t know exactly what it is, but if I had to guess (which I prefer not to do) it might have to do with the carrying of higher voltage which raises SINAD, but not enough to negate how much cleaner and more dynamic the actual playing of music is.
Talking about people who have owned them for decades and have owned many iterations. The ST70 is like the Chevy 350- it has a huge following and some people with no knowledge, as well as great circuit designers. It seems like we are here: “I measured Rosie o'donnell and Scarlett Johansson and Rosie is actually more symmetrical, so she is more attractive.” I am gonna say, “I believe your measurements and methodology, however, I think there might be some factors to consider or weigh differently- because I have personally seen them, and I gotta give it to Scarlett and everyone who has seen them kind of agrees.”ASR has the measurements to show us. Who are all of these "Dynaco experts", and what do they have to show us? Or you just talking about someone who has an opinion?
Remember:
View attachment 225657
Jim
OK I’ll bite lol. You mean all the new designers, or many of them, because all of the old school engineers measured everything, they were competing against each other with real measurements. Why would they go through all those measurements and list their specs if it didn’t mean anything? Contrary to popular belief, everything we hear can be measured, and not only that it was set in stone many moons ago.Talking about people who have owned them for decades and have owned many iterations. The ST70 is like the Chevy 350- it has a huge following and some people with no knowledge, as well as great circuit designers. It seems like we are here: “I measured Rosie o'donnell and Scarlett Johansson and Rosie is actually more symmetrical, so she is more attractive.” I am gonna say, “I believe your measurements and methodology, however, I think there might be some factors to consider or weigh differently- because I have personally seen them, and I gotta give it to Scarlett and everyone who has seen them kind of agrees.”
Obviously, it is everyone’s right to disregard, what almost all first hand experiences are. I know subjective reviews and first hand experiences are rife with issues, and this forum is great at removing that…at the same time, seems like objective and subjective should have a little better correlation. Especially, when all of the designers I know of agree that objectively great measurements doesn’t mean it sounds good. They battle to achieve both.
I never owned one but according to this list compiled by a member, the MC462 output 720 Watts in 4 ohms and achieve a SINAD of 108 dB I don't know but to me it's quite SOTA numbers, making it at Benchmark-Purifi-Hypex levels but with considerably more power. What's not to like? What makes them less legit than the old ones?MacIntosh as brand is not what it once was ,as so many hifi brands that's just husk of what they really where .
back in the day when they mattered , they where legit .
I admittedly know nothing about Google docs, although I share one document with a business associate. Is there a link to those documents from ASR, or way to search?I never owned one but according to this list compiled by a member, the MC462 output 720 Watts in 4 ohms and achieve a SINAD of 108 dB I don't know but to me it's quite SOTA numbers, making it at Benchmark-Purifi-Hypex levels but with considerably more power. What's not to like? What makes them less legit than the old ones?
Amplifier SINAD list ASR + 3rd parties
List Name,THD+N (5W, 4 ohms),SINAD (dB) (5W, 4 ohms),Power (W) (1% THD+N, 4 ohms),Price (USD),Source Topping LA90 (stereo, bypass, low gain),0.00009%,121,90,800,<a href="https://www.l7audiolab.com/f/topping-la90/">L7 Audio Lab</a>,Suggestions, corrections and more info here: Topping LA90 Discre...docs.google.com
To be honest I don't know much neither but for me it opens on both safari and chrome so seams you don't need the purely Google environment.I admittedly know nothing about Google docs, although I share one document with a business associate. Is there a link to those documents from ASR, or way to search?