• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Carver M-1.5t Review (Vintage Amp)

Rate this amplifier:

  • 1. Poor (headless panther)

    Votes: 102 48.8%
  • 2. Not terrible (postman panther)

    Votes: 83 39.7%
  • 3. Fine (happy panther)

    Votes: 13 6.2%
  • 4. Great (golfing panther)

    Votes: 11 5.3%

  • Total voters
    209

perdido34

Member
Joined
Dec 13, 2021
Messages
37
Likes
60
The m1.0 was used in the challenge, not the m1.5t, and the competitor was a Conrad Johnson, not a Mark Levinson, but you have raised a good point. Were the "t" series amps intentionally designed to have distortion levels that matched the Conrad Johnson? If so, that sheds a new light on this amp's performance, although not the lower than specified power. The CJs I heard were not good sounding amps, in my opinion.
There were two challenges. The 1982 challenge used the m1.5t vs. Levinson, the second (1985) was m1.0t vs. Conrad-Johnson. Go to this page and scroll down to Harvey Rosenberg's letter: https://www.stereophile.com/content/carver-challenge-responses
 

SimpleTheater

Addicted to Fun and Learning
Forum Donor
Joined
Jun 6, 2019
Messages
927
Likes
1,789
Location
Woodstock, NY
Power wise this amp is not in spec. These are 350W at 8 Ohm and THD ≤ 0.5% which is 46 dB. At that level your curve has barely exceeded 220W.
As the owner of a Carver 900 receiver (in my youth) I was always disappointed in the amp. It was rated at 90 watts per channel. Yet my previous receiver, a Technics SA-410, rated at 45 watts per channel, could push my speakers to much higher levels. I felt ripped off and never bought another Carver product.
 

Hipster Doofus

Active Member
Forum Donor
Joined
Sep 12, 2020
Messages
251
Likes
338
0478EEBB-E181-46F8-A12A-40483337AA78.jpeg

we’ve come a long way baby
 

beagleman

Major Contributor
Joined
Sep 24, 2020
Messages
1,159
Likes
1,582
Location
Pittsburgh Pa
As the owner of a Carver 900 receiver (in my youth) I was always disappointed in the amp. It was rated at 90 watts per channel. Yet my previous receiver, a Technics SA-410, rated at 45 watts per channel, could push my speakers to much higher levels. I felt ripped off and never bought another Carver product.

I think you need to define "much higher".....if it was even 3db louder, that means the Carver was really putting out only about 22 1/2 watts!

I hate to be one to call B.S. on a 40 year old story, but stuff back then was usually under rated a bit if anything.
 

SimpleTheater

Addicted to Fun and Learning
Forum Donor
Joined
Jun 6, 2019
Messages
927
Likes
1,789
Location
Woodstock, NY
I think you need to define "much higher".....if it was even 3db louder, that means the Carver was really putting out only about 22 1/2 watts!

I hate to be one to call B.S. on a 40 year old story, but stuff back then was usually under rated a bit if anything.

Being a kid at the time, I never measured anything. What I can say is I never had to put my Technics SA-410 past half way on the volume, but when I put the Carver 900 into my system, I had to crank it to three quarters to max to achieve my normal listening volume.
 

qec

Member
Joined
Apr 14, 2021
Messages
47
Likes
22
I have an Adcom GFA-555 currently sitting on a shelf but the cost to ship it to the west coast and back makes the whole operation expensive.
 

SIY

Grand Contributor
Technical Expert
Joined
Apr 6, 2018
Messages
10,386
Likes
24,752
Location
Alfred, NY
I have an Adcom GFA-555 currently sitting on a shelf but the cost to ship it to the west coast and back makes the whole operation expensive.
I have one as well. If there’s interest, I’ll run a measurement suite.
 

dfuller

Major Contributor
Joined
Apr 26, 2020
Messages
3,339
Likes
5,063
I'd be very curious to see what's going on with that residual switching noise.
 

capslock

Senior Member
Joined
Jun 19, 2020
Messages
316
Likes
145
Get hold of a pair of Kenwood LO-7M/mk2s or a Pioneer SA-9800 integrated. RETs/diffused emitter/LAPTs in another guise (Sanken and later Toshiba). The Fujitsu RETs were amazing when it came to high frequency, high power linearity when implemented well.
Toshiba, NEC and Fujitsu were RET, Sanken came in a little later. The NECs were reputed to have poor SOA, and I have had a pair going up in smoke before I knew what was going on. You don't happen to have full data sheets for NEC?
 

KEFCarver

Active Member
Joined
Mar 29, 2021
Messages
114
Likes
132
Location
Tucson, AZ
The M1.5T is from around 1985, at least there are ads for it in Audio Magazines at that time. The "T" designates it has a "Tube transfer Function". There was a much heralded challenge where Bob Carver tweaked this amp to sound like a much more expensive Krell tube amp(s ?), though there were a lot of flaws in this, you can read about that here:


I appreciate Amir reviewing this! I have a pair of Caver M400a cubes which are ~200w into 8ohms and 400w into 8ohms when bridged for mono, which is how I am using them. They also do not have a power switch, and now I know why as they are also magnetic field power amp designs- though they get switched on when the preamp comes on by a separate relay circuit due to the power they can pull. As far as I know they are original, and sound good and allow me to crank it up when I desire :D
 

Walter

Addicted to Fun and Learning
Joined
Aug 25, 2020
Messages
856
Likes
1,242
There were two challenges. The 1982 challenge used the m1.5t vs. Levinson, the second (1985) was m1.0t vs. Conrad-Johnson. Go to this page and scroll down to Harvey Rosenberg's letter: https://www.stereophile.com/content/carver-challenge-responses
That is partly correct. There was indeed a previous challenge against a pair of ML monoblocks, but they don't state which Carver amp was used. Either the Model 1.0, or the 1.5 (non-t). Rosenberg says the 1.5t was the RESULT of the challenge. It supposedly sounds like the modded amp Carver made for that challenge, although Rosenberg disputes this. (And the second challenge was the 1.0, not the 1.0t, which is the amp he made as the result of THAT challenge, I believe. There were a lot of revisions and mods to the Carver amps of that era.) Interesting read. It seems Bob Carver was already being accused of unethical behavior in 1986. I was really taken in by him.
 
Last edited:

SIY

Grand Contributor
Technical Expert
Joined
Apr 6, 2018
Messages
10,386
Likes
24,752
Location
Alfred, NY
That is partly correct. There was indeed a previous challenge against a pair of ML monoblocks, but they don't state which Carver amp was used. Either the Model 1.0, or the 1.5 (non-t). Rosenberg says the 1.5t was the RESULT of the challenge. It supposedly sounds like the modded amp Carver made for that challenge, although Rosenberg disputes this. (And the second challenge was the 1.0, not the 1.0t, which is the amp he made as the result of THAT challenge, I believe. There were a lot of revisions and mods to the Carver amps of that era.) Interesting read. It seems Bob Carver was already being accused of unethical behavior in 1986. I was really taken in by him.
Take the assertions with a large grain of salt. Rosenberg’s connections to truth and honesty were at best tenuous.
 

tomtoo

Major Contributor
Joined
Nov 20, 2019
Messages
3,607
Likes
4,514
Location
Germany
No it not measures perfect. But for its time it had a lot of power. And to some of the so(self) called high end amps, it was imo a good competitor. The good old times. ;)
 

SwampYankee

Member
Joined
Mar 2, 2021
Messages
41
Likes
53
I'd love to see the test results from the Adcom GFA555 to compare. I have a soft spot for Nelson Pass due to his generosity towards the DIY community and am curious how the GFA holds up in a battle of 40-year old designs. I spent hours in my youth drooling over both Carver (TFMs) and Adcom amps. They, and to a lesser extent, H/K and Bryston, were the high-end lines sold by the big electronics stores when I was in high school.
 

ta240

Major Contributor
Joined
Nov 7, 2019
Messages
1,358
Likes
2,656
As I noted in the review, owner had sent it in to have the capacitors upgraded.

It actually states that the owner replaced them "The owner has replaced the capacitors in this unit." Were they professionally done and was it an 'upgrade' or a 'replacement'? Those seem like different things that could affect the performance; especially since in the audiophile world upgrades often take things out of original spec.

Not knowing the quality and full extent of the work makes it a bit hard to judge. It is a bit like driving a 35 year old car and judging the company that built it rather than the people that maintained it.
 

phoenixdogfan

Major Contributor
Forum Donor
Joined
Nov 6, 2018
Messages
3,297
Likes
5,079
Location
Nashville
A lot was made in the day how Carver knew how to make solid state amps sound like tube amps by altering the amps transfer function. Peter Aczel explained it in detail in the old Audio Critic. One of the first amps, the MC 400, I think, was altered to sound just like the Conrad Johnson Premier 1 which was a 150 lb tube behemoth putting out over 300 wpc, and costing over $5k in the early '80's. At the time the CJ was Absolute Sound's choice for best sounding amp of all time, and was one of the products that started the preposterous pricing escalation of audio gear resulting in the routinely priced $50 k "flagship" amps, dacs and preamps we see today.

If Carver's amps were made to mimic the characteristic tube amplifier sound is it any wonder we are seeing the poor distortion numbers Amir has measured on two of these products?

I think we might see better number on some of the solid state classics of the day, though not the Levlinson ML-2 which was designed to run in pure class A with zero negative feedback. But something like a Hafler DH 200 would be an interesting review from this era, and might have performance numbers in line with today's solidly engineered class AB designs.
 
Top Bottom