SoCal Sam
Lunatic Member
You may remember Bond's recent post of Stereo Review magazine scans of the Marantz 2500 and SX-1980 reviews. As a new owner of a 2500, Bond was kind enough to e-mail me clearer scans. Since I had already squinted through and typed about two thirds of the text from the old scans, here is the rest. Please enjoy this as much as I have. THANKS BOND.
STEREO REVIEW. February, 1978
Equipment Test Reports
By Hirsch-Houck Laboratories
Marantz 2500 AM/FM Stereo Receiver
Receivers have come a long way from their very humble beginnings twenty or so years ago as an economical combination of a basic preamplifier, a (usually) unexceptional AM/FM tuner, and a low powered amplifier. With today’s power race between receiver manufacturers we have reached the point where the current champion, the Marantz 2500, carries a hefty 250 watt per channel rating. And all of the other attributes of a high-quality separate component system, including control flexibility and tuner performance, have been scaled up to match.
Although space does not permit even an abbreviated discussion of the many advanced circuit features of the 2500, its key performance ratings are a clue to its potential. For example, the audio power rating of 250 watts per channel into 8-ohm loads from 20 to 20,000 Hz, with less than 0.05 per cent distortion, would make the Marantz 2500 a formidable contender among super-power amplifiers, let alone receivers. But, unlike most amplifiers and receivers, the 2500 also has a full-fledged “FTC” 4-ohm rating of 330 watts per channel from 20 to 20,000 Hz with less than 0.08 per cent distortion. The FM Tuner ratings include a 12.1 dBf 50-dB quieting sensitivity, mono and stereo distortion of 0.1 and 0.2 per cent respectively, and 50 dB of mid-range stereo separation. The 2500 is not much larger than other receivers with half its power. Its front panel, in satin-finished gold, has the familiar Marantz horizontal tuning control. On the dial plate, with its blue-lit calibration indicator, are red indicators for STEREO and DLB-1 (an optional Dolby FM decoder).
To the left of the dial area is the oscilloscope display, which has traditionally been a feature of the top-ranking tuner in the Marantz line. The 2-inch-diameter cathode ray tube serves as an AM and FM tuning indicator (showing relative signal strength vertically and FM tuning error horizontally), a mulitpath direction indicator, and an audio X-Y display of both channels simultaneously. Next to the scope tube are its spot-positioning controls and the audio-display level control. LED’s below the dial identify the selected program source (AM, FM, Phono 1, Phono 2, AUX, and TAPE). Separate PEAK lights for the two channels flash when the instantaneous power approaches the maximum capability of the amplifier.
Across the full width of the panel, below the dial and scope, is a row of fifteen pushbutton position switches. Four of them cross-connect two tape decks for dubbing from either one to the other and provide tape monitoring from either deck. Other buttons turn on the oscilloscope and select its display. Following a horizontal slider BALANCE control with a center detent are buttons that control the low-frequency (15-Hz) and high frequency (9,000 Hz) filters, both of which have 18-dB-per-octave slopes. The remaining buttons control loudness compensation, the MPX NOISE FILTER and FM interstation-noise setting. There are separate switches for the two sets of speaker outputs.
The knob-operated controls are in a row along the bottom right edge of the panel. The input selector is conventional, except for its inclusion of a second FM position for Dolby encoded broadcasts. This not only changes the FM de-emphasis from 75 to 25 microseconds, but also connects the DLB-1 Dolby module if it has been plugged into its receptacle in the rear of the receiver. Each of the three eleven position line controls BASS, MID, and TREBLE is a concentric pair with slip-clutch coupling for independent adjustment of the two channels.
The TONE MODE control knob of the Marantz 2500 has five positions including IN and OUT settings so that the controls can be bypassed. The position marked 100 Hz changes the bass turnover frequency from its normal (but unspecified) value to 100 Hz and the 10 kHz position does the same thing for the treble control. Finally the 100 Hz / 10 kHz position shifts the turnover frequencies of both controls to their alternative values. The midrange tone control is unaffected by these actions but it too is bypassed in the OUT position of the control.
Completing the front-panel features are the volume control control (with forty lightly detented positions), the pushbutton power switch, a headphone jack, and two tape-dubbing jacks (IN and OUT) for connecting a tape deck through the front of the receiver. When this is done, the rear TAPE 2 circuits are bypassed.
On the rear apron of the Marantz 2500, in addition to the various signal connectors, there are PRE OUT and MAIN IN jacks for inserting accessories between the preamplifier and power amplifier, and an output jack for possible use in some future discrete four channel FM decoder. A rectangular socket accepts the optional DLB-1 Dolby Module. When installed, it is controlled by the front panel input selector in its 25 microsecond position. Insulated spring clips are used for the speaker outputs and binding posts for the antenna connections. There is a pivoted ferrite-rod AM antenna. Screwdriver adjustments control the brightness and focus of the oscilloscope and the FM muting threshold. One of the two a.c. outlets is switched (both are of the three prong grounding type).
A prominent feature of the rear apron is the cooiling fan exhaust. The output transistors of the Marantz 2500 are mounted in a rectangular tunnel, with long individual cooling fins (actually rods) attached to the transistors and extending into the tunnel. The fan draws air from the top of the cabinet throught the tunnel and expels it out the rear. Normally it operates at a very low speed, but if the temperature rises beyond a certain point the fan automatically switches to a higher speed. The Marantz 2500 is 19 ¾ inches wide, 7 inches high, and 17 ¼ inches deep. It weighs just under 60 pounds. Price: $1750. A walnut-veneer wooden cabinet is available as an option (about $45). The Dolby module DLB-1 is about $50.
LABORATORY MEASUREMENTS. The most impressive feature of the Marantz 2500, from the standpoint of our laboratory test, was its totally cool operation. At no time during the FTC preconditioning period or the high-power tests that followed did any part of its exterior become faintly warm to the touch. We have never encountered any other audio component that remained as cool in operation as the Marantz 2500.
Under normal conditions, the fan operates so slowly that it cannot be heard, even close up. Only a faintly warm, barely perceptible breeze emerging from the rear of the fan grill gives a hint of its presence. After about five minutes of one-third power operation the fan switched to high speed with a roar that could hardly be overlooked. Since this would happen only when the amplifier was delivering considerable power (presumably to loudspeakers), it is unlikely that it would present any problems in actual practice. The thermal “inertia” of the cooling rods is apparently quite low, since a minute or two after a normal power-output level was restored the fan dropped back to its lower speed.
In its fully “heated” condition, the Marantz 2500 delivered 306 watts per channel to 8-ohm loads (at 1,000 Hz) at the clipping point. The 4- and 16-ohm clipping outputs were 473 (!) and 189 watts per channel, respectively. At 1,000 Hz, the harmonic distortion was less than the residual of our test equipment (about 0.003 per cent) from 0.1 to 100 watts, increasing to a barely measurable 0.0035 per cent at 250 watts and 0.0045 per cent at 300 watts just before clipping. The intermodulation distortion (IM) was between 0.005 and 0.01 per cent at 200 watts, and 0.05 per cent at 250 watts. At the rated 250-watt output, the total harmonic distortion (THD) of the Marantz 2500 was less than 0.003 per cent between 300 and 4,000 Hz and about 0.02 per cent at 20 Hz and 20,000 Hz. It was not significantly different at lower power levels.
The AUX-input sensitivity was high, so that only 36 millivolts input was needed for a 10-watt reference output. The phono sensitivity was 0.38 millivolt. The respective unweighted signal-to-noise ratios were 79 and 69 dB. The phono input, in spite of its high gain, did not overload until a very high 220-millivolt input was applied.
The tone controls could be set to produce almost any desired frequency response. When the 100-Hz/10-kHz switch setting was used, the control action was very subtle and concentrated near the limits of audibility. In the “normal” condition, the bass turnover frequency was adjustable from about 150 to 400 Hz and the treble-control action hinged at about 3,000 Hz. The mid-range control had its principal effect between 600 and 1,200 Hz.
The 15-Hz filter had no significant effect in the audio-frequency range. We would suggest leaving it switched in at all times, since this amplifier is capable of destroying most speakers if, for example, somebody dropped a pickup onto the surface of a record. The high-frequency filter response was down 3 dB at 9,000 Hz, as rated, and its 18-dB-per-octave slope makes it one of the most effective high-cut filters we have seen in many years. The loudness-control action was moderate, and it boosted both low and high frequencies. The RIAA phono equalization was flat, within {plus-minus} 0.25 dB over the extended range of 20 to 20,000 Hz. When measured through the inductance of a phono cartridge, the phono response rose slightly at high frequencies to a maximum of +1.5 dB at 20,000 Hz.
The performance of the FM tuner section provided a few surprises also. The IHF usable sensitivity of 10.25 dBf or 1.8 microvolts (uV) was good by any standards, but this is one of the rare receivers whose quieting curve is so steep that its 50-dB quieting sensitivity us less than its IHF sensitivity. In this case it was at 8.25 dBf (1.5 uV), with 5.6 per cent THD. This indicates that the tuner quiets at remarkably low signal levels, while its distortion characteristics are more “normal” for a top quality tuner. The stereo IHF usable sensitivity was 15 dBf (3 uV), set by the stereo switch threshold, and the 50-dB quieting point was reached at 33 dBf (24 uV) with 0.7 per cent THD (also representing above-average stereo performance).
The ultimate quieting was 71.5 dB in mono and 70.5 dB in stereo, but these figures were limited by the tuner’s residual ( and inaudible) hum rather than by its hiss level. The FM distortion was 0.13 per cent in mono and 0.15 per cent in stereo. In stereo, with out-of-phase (L – R) modulation, it was 0.36 per cent at 100 Hz, 0.1 per cent ar 1,000 Hz, and 0.56 per cent at 6,000 Hz.
The stereo-FM frequency response was within {plus-minus} 0.2 dB over the full 30- to 15,000 Hz measurement range (and it was down only 0.3 dB from its mid-range level at 15,000 Hz). The channel separation was between 50 and 57.5 dB at frequencies from 350 to 8,500 Hz; it was 40 dB at 30 Hz and 37 dB at 15,000 Hz.
The FM capture ratio was 1.05 dB at a 65-dBf (1,000-uV) input and 1.56 dB at 45 dBf (100uV). The respective AM rejection figures at these inputs were 63 and 72 dB. The image rejection was 88.5 dB and alternate-channel selectivity was 76 dB. Adjacent-channel selectivity was 9 dB. The factiry setting of the muting threshold was 17 dBf (3.8 uV), which we found perfectly satisfactory, although it could have been adjusted easily if this had been desired. The stereo switching threshold was 15 dBf (3 uV). The 19-Hz pilot carrier leakage was -70 dB, and the tuner’s hum level was -71 dB. The only measurement made on the AM tuner section was of its frequency response, which was down 4.5 dB at 20 Hz and 5 dB at 4,000 Hz relative to 1,000-Hz.
COMMENT. If we had to give a capsule review of the Marantz 2500, we would say that (for a receiver, at least) it has an average quality AM tuner, a considerably better-than-average FM tuner, and a superb audio amplifier. The amplifier should not be compared only to those in other receivers. It ranks with the most powerful amplifiers one can buy for home use, and it is a very, very good one in addition to being the coolest, by far, that we have tested. For those who are concerned with slew-rate considerations, we measured a 30-volt-per-microsecond slew rate on the Marantz 2500, which is certainly more than adequate. Also, with a mixed 19,000- and 20,000-Hz input signal driving the amplifier to within 0.1 dB of its clipping condition, the only distortion product detectable in the audio range was a -76-dB component at the 1,000-Hz difference frequency.
Obviously, in matters of performance, the Marantz 2500 is a truly first-rate product. What about the human-engineering aspects of this massive “all-in-one” unit? In most respects we would have to rate it good to excellent. An oscilloscope, though expensive, is the ideal tuning and multipath-distortion indicator. All the controls worked smoothly, with no surprises (and with all that power available, there had better not be any sudden noises!). The Dolby-FM sound was truly excellent, and this is one of the few receivers with Dolby processing that makes Dolby broadcasts sound unequivocally better than they do in their unprocessed state with a 75-microsecond tuner de-emphasis.
We found that the Model 2500 was far easier to handle and install than its 60 pounds would suggest. A centrally located toroidal-transformer power supply, which minimizes mass unbalance, is largely responsible for this happy fact. In addition, we are pleased to note that the receiver is somewhat lighter than many of its less powerful competitors.
Our one complaint about the Marantz 2500 is that, when listening to FM even with our least efficient speakers, we were never able to operate the volume control above the lowest quarter of its range. With more normally efficient speakers we rarely moved the knob beyond the lowest four or five steps (out of a total of forty). This is a function of the tuner-level adjustment accessible from the rear or bottom of the receiver would have been helpful.
As for the possible risk of putting all one’s hi-fi eggs in a single $1,750 basket, we can only point out that the Marantz 2500 is a wonderfully robust, cool-running “basket” that evidences an intelligent, conservative, state-of-the-art design approach throughout.
STEREO REVIEW. February, 1978
Equipment Test Reports
By Hirsch-Houck Laboratories
Marantz 2500 AM/FM Stereo Receiver
Receivers have come a long way from their very humble beginnings twenty or so years ago as an economical combination of a basic preamplifier, a (usually) unexceptional AM/FM tuner, and a low powered amplifier. With today’s power race between receiver manufacturers we have reached the point where the current champion, the Marantz 2500, carries a hefty 250 watt per channel rating. And all of the other attributes of a high-quality separate component system, including control flexibility and tuner performance, have been scaled up to match.
Although space does not permit even an abbreviated discussion of the many advanced circuit features of the 2500, its key performance ratings are a clue to its potential. For example, the audio power rating of 250 watts per channel into 8-ohm loads from 20 to 20,000 Hz, with less than 0.05 per cent distortion, would make the Marantz 2500 a formidable contender among super-power amplifiers, let alone receivers. But, unlike most amplifiers and receivers, the 2500 also has a full-fledged “FTC” 4-ohm rating of 330 watts per channel from 20 to 20,000 Hz with less than 0.08 per cent distortion. The FM Tuner ratings include a 12.1 dBf 50-dB quieting sensitivity, mono and stereo distortion of 0.1 and 0.2 per cent respectively, and 50 dB of mid-range stereo separation. The 2500 is not much larger than other receivers with half its power. Its front panel, in satin-finished gold, has the familiar Marantz horizontal tuning control. On the dial plate, with its blue-lit calibration indicator, are red indicators for STEREO and DLB-1 (an optional Dolby FM decoder).
To the left of the dial area is the oscilloscope display, which has traditionally been a feature of the top-ranking tuner in the Marantz line. The 2-inch-diameter cathode ray tube serves as an AM and FM tuning indicator (showing relative signal strength vertically and FM tuning error horizontally), a mulitpath direction indicator, and an audio X-Y display of both channels simultaneously. Next to the scope tube are its spot-positioning controls and the audio-display level control. LED’s below the dial identify the selected program source (AM, FM, Phono 1, Phono 2, AUX, and TAPE). Separate PEAK lights for the two channels flash when the instantaneous power approaches the maximum capability of the amplifier.
Across the full width of the panel, below the dial and scope, is a row of fifteen pushbutton position switches. Four of them cross-connect two tape decks for dubbing from either one to the other and provide tape monitoring from either deck. Other buttons turn on the oscilloscope and select its display. Following a horizontal slider BALANCE control with a center detent are buttons that control the low-frequency (15-Hz) and high frequency (9,000 Hz) filters, both of which have 18-dB-per-octave slopes. The remaining buttons control loudness compensation, the MPX NOISE FILTER and FM interstation-noise setting. There are separate switches for the two sets of speaker outputs.
The knob-operated controls are in a row along the bottom right edge of the panel. The input selector is conventional, except for its inclusion of a second FM position for Dolby encoded broadcasts. This not only changes the FM de-emphasis from 75 to 25 microseconds, but also connects the DLB-1 Dolby module if it has been plugged into its receptacle in the rear of the receiver. Each of the three eleven position line controls BASS, MID, and TREBLE is a concentric pair with slip-clutch coupling for independent adjustment of the two channels.
The TONE MODE control knob of the Marantz 2500 has five positions including IN and OUT settings so that the controls can be bypassed. The position marked 100 Hz changes the bass turnover frequency from its normal (but unspecified) value to 100 Hz and the 10 kHz position does the same thing for the treble control. Finally the 100 Hz / 10 kHz position shifts the turnover frequencies of both controls to their alternative values. The midrange tone control is unaffected by these actions but it too is bypassed in the OUT position of the control.
Completing the front-panel features are the volume control control (with forty lightly detented positions), the pushbutton power switch, a headphone jack, and two tape-dubbing jacks (IN and OUT) for connecting a tape deck through the front of the receiver. When this is done, the rear TAPE 2 circuits are bypassed.
On the rear apron of the Marantz 2500, in addition to the various signal connectors, there are PRE OUT and MAIN IN jacks for inserting accessories between the preamplifier and power amplifier, and an output jack for possible use in some future discrete four channel FM decoder. A rectangular socket accepts the optional DLB-1 Dolby Module. When installed, it is controlled by the front panel input selector in its 25 microsecond position. Insulated spring clips are used for the speaker outputs and binding posts for the antenna connections. There is a pivoted ferrite-rod AM antenna. Screwdriver adjustments control the brightness and focus of the oscilloscope and the FM muting threshold. One of the two a.c. outlets is switched (both are of the three prong grounding type).
A prominent feature of the rear apron is the cooiling fan exhaust. The output transistors of the Marantz 2500 are mounted in a rectangular tunnel, with long individual cooling fins (actually rods) attached to the transistors and extending into the tunnel. The fan draws air from the top of the cabinet throught the tunnel and expels it out the rear. Normally it operates at a very low speed, but if the temperature rises beyond a certain point the fan automatically switches to a higher speed. The Marantz 2500 is 19 ¾ inches wide, 7 inches high, and 17 ¼ inches deep. It weighs just under 60 pounds. Price: $1750. A walnut-veneer wooden cabinet is available as an option (about $45). The Dolby module DLB-1 is about $50.
LABORATORY MEASUREMENTS. The most impressive feature of the Marantz 2500, from the standpoint of our laboratory test, was its totally cool operation. At no time during the FTC preconditioning period or the high-power tests that followed did any part of its exterior become faintly warm to the touch. We have never encountered any other audio component that remained as cool in operation as the Marantz 2500.
Under normal conditions, the fan operates so slowly that it cannot be heard, even close up. Only a faintly warm, barely perceptible breeze emerging from the rear of the fan grill gives a hint of its presence. After about five minutes of one-third power operation the fan switched to high speed with a roar that could hardly be overlooked. Since this would happen only when the amplifier was delivering considerable power (presumably to loudspeakers), it is unlikely that it would present any problems in actual practice. The thermal “inertia” of the cooling rods is apparently quite low, since a minute or two after a normal power-output level was restored the fan dropped back to its lower speed.
In its fully “heated” condition, the Marantz 2500 delivered 306 watts per channel to 8-ohm loads (at 1,000 Hz) at the clipping point. The 4- and 16-ohm clipping outputs were 473 (!) and 189 watts per channel, respectively. At 1,000 Hz, the harmonic distortion was less than the residual of our test equipment (about 0.003 per cent) from 0.1 to 100 watts, increasing to a barely measurable 0.0035 per cent at 250 watts and 0.0045 per cent at 300 watts just before clipping. The intermodulation distortion (IM) was between 0.005 and 0.01 per cent at 200 watts, and 0.05 per cent at 250 watts. At the rated 250-watt output, the total harmonic distortion (THD) of the Marantz 2500 was less than 0.003 per cent between 300 and 4,000 Hz and about 0.02 per cent at 20 Hz and 20,000 Hz. It was not significantly different at lower power levels.
The AUX-input sensitivity was high, so that only 36 millivolts input was needed for a 10-watt reference output. The phono sensitivity was 0.38 millivolt. The respective unweighted signal-to-noise ratios were 79 and 69 dB. The phono input, in spite of its high gain, did not overload until a very high 220-millivolt input was applied.
The tone controls could be set to produce almost any desired frequency response. When the 100-Hz/10-kHz switch setting was used, the control action was very subtle and concentrated near the limits of audibility. In the “normal” condition, the bass turnover frequency was adjustable from about 150 to 400 Hz and the treble-control action hinged at about 3,000 Hz. The mid-range control had its principal effect between 600 and 1,200 Hz.
The 15-Hz filter had no significant effect in the audio-frequency range. We would suggest leaving it switched in at all times, since this amplifier is capable of destroying most speakers if, for example, somebody dropped a pickup onto the surface of a record. The high-frequency filter response was down 3 dB at 9,000 Hz, as rated, and its 18-dB-per-octave slope makes it one of the most effective high-cut filters we have seen in many years. The loudness-control action was moderate, and it boosted both low and high frequencies. The RIAA phono equalization was flat, within {plus-minus} 0.25 dB over the extended range of 20 to 20,000 Hz. When measured through the inductance of a phono cartridge, the phono response rose slightly at high frequencies to a maximum of +1.5 dB at 20,000 Hz.
The performance of the FM tuner section provided a few surprises also. The IHF usable sensitivity of 10.25 dBf or 1.8 microvolts (uV) was good by any standards, but this is one of the rare receivers whose quieting curve is so steep that its 50-dB quieting sensitivity us less than its IHF sensitivity. In this case it was at 8.25 dBf (1.5 uV), with 5.6 per cent THD. This indicates that the tuner quiets at remarkably low signal levels, while its distortion characteristics are more “normal” for a top quality tuner. The stereo IHF usable sensitivity was 15 dBf (3 uV), set by the stereo switch threshold, and the 50-dB quieting point was reached at 33 dBf (24 uV) with 0.7 per cent THD (also representing above-average stereo performance).
The ultimate quieting was 71.5 dB in mono and 70.5 dB in stereo, but these figures were limited by the tuner’s residual ( and inaudible) hum rather than by its hiss level. The FM distortion was 0.13 per cent in mono and 0.15 per cent in stereo. In stereo, with out-of-phase (L – R) modulation, it was 0.36 per cent at 100 Hz, 0.1 per cent ar 1,000 Hz, and 0.56 per cent at 6,000 Hz.
The stereo-FM frequency response was within {plus-minus} 0.2 dB over the full 30- to 15,000 Hz measurement range (and it was down only 0.3 dB from its mid-range level at 15,000 Hz). The channel separation was between 50 and 57.5 dB at frequencies from 350 to 8,500 Hz; it was 40 dB at 30 Hz and 37 dB at 15,000 Hz.
The FM capture ratio was 1.05 dB at a 65-dBf (1,000-uV) input and 1.56 dB at 45 dBf (100uV). The respective AM rejection figures at these inputs were 63 and 72 dB. The image rejection was 88.5 dB and alternate-channel selectivity was 76 dB. Adjacent-channel selectivity was 9 dB. The factiry setting of the muting threshold was 17 dBf (3.8 uV), which we found perfectly satisfactory, although it could have been adjusted easily if this had been desired. The stereo switching threshold was 15 dBf (3 uV). The 19-Hz pilot carrier leakage was -70 dB, and the tuner’s hum level was -71 dB. The only measurement made on the AM tuner section was of its frequency response, which was down 4.5 dB at 20 Hz and 5 dB at 4,000 Hz relative to 1,000-Hz.
COMMENT. If we had to give a capsule review of the Marantz 2500, we would say that (for a receiver, at least) it has an average quality AM tuner, a considerably better-than-average FM tuner, and a superb audio amplifier. The amplifier should not be compared only to those in other receivers. It ranks with the most powerful amplifiers one can buy for home use, and it is a very, very good one in addition to being the coolest, by far, that we have tested. For those who are concerned with slew-rate considerations, we measured a 30-volt-per-microsecond slew rate on the Marantz 2500, which is certainly more than adequate. Also, with a mixed 19,000- and 20,000-Hz input signal driving the amplifier to within 0.1 dB of its clipping condition, the only distortion product detectable in the audio range was a -76-dB component at the 1,000-Hz difference frequency.
Obviously, in matters of performance, the Marantz 2500 is a truly first-rate product. What about the human-engineering aspects of this massive “all-in-one” unit? In most respects we would have to rate it good to excellent. An oscilloscope, though expensive, is the ideal tuning and multipath-distortion indicator. All the controls worked smoothly, with no surprises (and with all that power available, there had better not be any sudden noises!). The Dolby-FM sound was truly excellent, and this is one of the few receivers with Dolby processing that makes Dolby broadcasts sound unequivocally better than they do in their unprocessed state with a 75-microsecond tuner de-emphasis.
We found that the Model 2500 was far easier to handle and install than its 60 pounds would suggest. A centrally located toroidal-transformer power supply, which minimizes mass unbalance, is largely responsible for this happy fact. In addition, we are pleased to note that the receiver is somewhat lighter than many of its less powerful competitors.
Our one complaint about the Marantz 2500 is that, when listening to FM even with our least efficient speakers, we were never able to operate the volume control above the lowest quarter of its range. With more normally efficient speakers we rarely moved the knob beyond the lowest four or five steps (out of a total of forty). This is a function of the tuner-level adjustment accessible from the rear or bottom of the receiver would have been helpful.
As for the possible risk of putting all one’s hi-fi eggs in a single $1,750 basket, we can only point out that the Marantz 2500 is a wonderfully robust, cool-running “basket” that evidences an intelligent, conservative, state-of-the-art design approach throughout.
