mkmelt
500+ Head-Fier
- Joined
- Jun 14, 2002
- Posts
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I recently purchased a ste of Sennheiser HD-600 headphones after reading the forums on this site. I have had a chance to do some listening to the HD-600s using some of my collection of vintage 60s, 70s, and 80s audio equipment.
So far, I have listened to them using four pieces of vintage equipment:
1) Marantz 2235B stereo receiver with 1/4" headphone jack. This is a vintage 1975 receiver, from the period when Marantz still built some of the best consumer audio equipment. 35 watts/channel, built like a tank, large chassis, heavy massive power supply.
The Marantz easily drives the 600s, with a full range sound with very deep well defined bass. I have only listened to FM radio, but classical, jazz, and rock music sound great on the 600s through the Marantz. The low frequency response of the 600s is very solid and extended when connected to the Marantz. Also, good soundstage is evident, better than when listening to my Yahama YH-1 headphones connected to the Marantz.
2) Denon DCD-1500 CD player with a 1/4" headphone jack. While dated compared to today's players, the DCD-1500 was one of the better CD players when it was introduced in 1985/86.
The Denon had no problem driving the 600s to acceptable volume level. The sound was clear and detailed, especially in the upper range. The lowest two - three octaves were rolled off, say below 100 Hz. The 600s still sounded good but the sound was not as full as I had experienced when connected to my Marantz receiver.
3) Hafler DH-110 Preampflier with a 1/4" headphone jack.
I built this from a kit, to match my Hafler DH-200A amplfier also built from a kit. The DH-110 uses all discrete components and has precision switches and controls.
The Hafler DH-110 specification sheet states that it can produce an output level of 3.5 Volts nominal, 14 Volts RMS maximum output. The Hafler had no problem driving the 600s to loud levels. The sound was full, with none of the bass roll off I heard through the Denon CD player headphone output. However, the upper range was a bit recessed, and did not have the clarity I heard when the 600s were fed directly from the Denon. This confirms something I had already learned, that my CD player sounded better when its output was fed directly to the dual mono amplifiers I use to drive my Magneplanar MG-1 loudspeakers.
4) Fisher 400 FM Multiplex stereo tube receiver. This 1960s receiver is the last all-tube model receiver sold by Fisher. The amplifier output section uses (4) - 7868 output tubes for a rated 28 watts/channel at 8 ohms. The 1/4" headphone jack is wired with left and right channels reversed, dunno if this is normal or a goof. I have a slightly later vintage Fisher solid state receiver called Futura Series 201, and it also had the left and right channels wired reversed on the headphone jack. I had this corrected while the model 201 was being checked out and the FM section realigned.
I have to agree with TuberRoller and Dan H about the fantastic sound of these old Fisher components. The Fisher 400 never ceases to amaze me with its effortless, natural sound. Male and female voices emerge from both speakers and headphones with such a sense of three dimensionality that it's kinda spooky. Also electric guitars have a depth of sound that makes you feels as if you can get inside of and look around the notes as they hang in the air aroung your head. Using the Fisher, the HD-600s are driven to normal listening levels much easier than was the case with my Yamaha YH-1 phones. I don't recall the impedance of the Yahamas, I believe it may be 300 ohms, in any event the 600s are easier to drive to normal and above normal levels. The sound is first rate, even more natural and with a clarity beyond anything I have heard from my Yahamas used with the Fisher.
I realize this is a headphone forum, but if anyone is wondering what's the big deal with tube amplifiers and headphones, after a number of months listening to the Fisher with CDs, FM, and reel to reel tapes I have formed my own opinion about the special magic of tube audio.
First, when listening to any source, but especially a well recorded analog source, the ambience of the recording session (instrument, room, booth , studio,and hall ambience, etc.) passes through the tube circuits intact and actually gets to the speaker terminals or headphone jack. This ambience is sometimes so strong, you swear that they added artificial reverb in the studio. The wide-range sound of the 600s make recorded ambience easy to hear and appreciate. It is rare to hear this level of ambient sound on most CDs, but whether natural or artificial, it can be more fully experienced with a good tube amplifier or receiver such as the Fisher 400.
Second, wide-range dynamics. The crash of a cymbol or a drum being kicked, or an orchestra hitting a crescendo in the music will momentarily require the amplifier to deliver signal peaks that are higher than its rated output. I think two things happen here that make tube amplifiers handle musical peaks with greater ease. The first is less well known. The power supply sections of tube amplifiers, especially the vintage ones, use very high voltages (greater than +400 Volts). They store their extra energy in power supply capacitors just like solid state amplifiers. The difference, however, is that solid state amplifiers need capacitors that are able to store tens of thousands of microfarads of charge at their lower operating voltages (+ 14 volts) to equal the amount of energy in joules stored in the power supply capacitors of a vintage tube amplifier charged with only a few hundred microfarads, because of the higher voltages used. The net effect is that the tube amplifier is able to handle musical peaks in a way that solid state equipment can't match. The other reason, more well known reason, is that when tubes reach their maximum output, they clip the signal in a way that is less harsh, with even-order distortions that the human brain finds less grating than the odd order harmonics generated when transistors clip their output signals. What does this have to do with headphones? Well, the HD-600s are capable of very wide dynamic range. When they are fed a clean peak signal from an amplifier, they accurately recreate the musical dynamics present in the signal. With good tube amplification, this makes for hearing some very natural sounding musical peaks on the HD-600s without any harshness.
Regarding the bass, I found the bass reproduction of the HD-600s, while listening to them using the Fisher 400, to be very satisfying and natural. However, I did not hear the same level of power and authority of the lowest octaves, say 50 Hz and below the way I did when listening to the 600s using the Marantz receiver. I believe the reason is that the Fisher rolls off response in the lowest octaves due to the impedance matching output transformers that are part of the output circuitry. These transformers are also responsible for much of the tube sound quality that is so highly prized in these vintage units, so its a trade off but one I would happily make to enjoy the highly musical reproduction of the Fisher 400. Suffice to say that the HD-600s can play much deeper in the bass than the Fisher 400 does, and the HD-600s reproduce all of the bass and other frequencies passing through the Fisher's output tubes and output transformers with ease. It is a joy to listen to the wide-range, dynamic sound of the HD-600s when connected to the Fisher's headphone jack. I guess I could intentionally reverse the leads on the HD-600s to correct the left/right channel reversal of the Fisher's headphone jack. For now, since all of my critical listening with the Fisher tends to be reel to reel tape, I simply reversed the left and right tape inputs to the Fisher.
-Marc
So far, I have listened to them using four pieces of vintage equipment:
1) Marantz 2235B stereo receiver with 1/4" headphone jack. This is a vintage 1975 receiver, from the period when Marantz still built some of the best consumer audio equipment. 35 watts/channel, built like a tank, large chassis, heavy massive power supply.
The Marantz easily drives the 600s, with a full range sound with very deep well defined bass. I have only listened to FM radio, but classical, jazz, and rock music sound great on the 600s through the Marantz. The low frequency response of the 600s is very solid and extended when connected to the Marantz. Also, good soundstage is evident, better than when listening to my Yahama YH-1 headphones connected to the Marantz.
2) Denon DCD-1500 CD player with a 1/4" headphone jack. While dated compared to today's players, the DCD-1500 was one of the better CD players when it was introduced in 1985/86.
The Denon had no problem driving the 600s to acceptable volume level. The sound was clear and detailed, especially in the upper range. The lowest two - three octaves were rolled off, say below 100 Hz. The 600s still sounded good but the sound was not as full as I had experienced when connected to my Marantz receiver.
3) Hafler DH-110 Preampflier with a 1/4" headphone jack.
I built this from a kit, to match my Hafler DH-200A amplfier also built from a kit. The DH-110 uses all discrete components and has precision switches and controls.
The Hafler DH-110 specification sheet states that it can produce an output level of 3.5 Volts nominal, 14 Volts RMS maximum output. The Hafler had no problem driving the 600s to loud levels. The sound was full, with none of the bass roll off I heard through the Denon CD player headphone output. However, the upper range was a bit recessed, and did not have the clarity I heard when the 600s were fed directly from the Denon. This confirms something I had already learned, that my CD player sounded better when its output was fed directly to the dual mono amplifiers I use to drive my Magneplanar MG-1 loudspeakers.
4) Fisher 400 FM Multiplex stereo tube receiver. This 1960s receiver is the last all-tube model receiver sold by Fisher. The amplifier output section uses (4) - 7868 output tubes for a rated 28 watts/channel at 8 ohms. The 1/4" headphone jack is wired with left and right channels reversed, dunno if this is normal or a goof. I have a slightly later vintage Fisher solid state receiver called Futura Series 201, and it also had the left and right channels wired reversed on the headphone jack. I had this corrected while the model 201 was being checked out and the FM section realigned.
I have to agree with TuberRoller and Dan H about the fantastic sound of these old Fisher components. The Fisher 400 never ceases to amaze me with its effortless, natural sound. Male and female voices emerge from both speakers and headphones with such a sense of three dimensionality that it's kinda spooky. Also electric guitars have a depth of sound that makes you feels as if you can get inside of and look around the notes as they hang in the air aroung your head. Using the Fisher, the HD-600s are driven to normal listening levels much easier than was the case with my Yamaha YH-1 phones. I don't recall the impedance of the Yahamas, I believe it may be 300 ohms, in any event the 600s are easier to drive to normal and above normal levels. The sound is first rate, even more natural and with a clarity beyond anything I have heard from my Yahamas used with the Fisher.
I realize this is a headphone forum, but if anyone is wondering what's the big deal with tube amplifiers and headphones, after a number of months listening to the Fisher with CDs, FM, and reel to reel tapes I have formed my own opinion about the special magic of tube audio.
First, when listening to any source, but especially a well recorded analog source, the ambience of the recording session (instrument, room, booth , studio,and hall ambience, etc.) passes through the tube circuits intact and actually gets to the speaker terminals or headphone jack. This ambience is sometimes so strong, you swear that they added artificial reverb in the studio. The wide-range sound of the 600s make recorded ambience easy to hear and appreciate. It is rare to hear this level of ambient sound on most CDs, but whether natural or artificial, it can be more fully experienced with a good tube amplifier or receiver such as the Fisher 400.
Second, wide-range dynamics. The crash of a cymbol or a drum being kicked, or an orchestra hitting a crescendo in the music will momentarily require the amplifier to deliver signal peaks that are higher than its rated output. I think two things happen here that make tube amplifiers handle musical peaks with greater ease. The first is less well known. The power supply sections of tube amplifiers, especially the vintage ones, use very high voltages (greater than +400 Volts). They store their extra energy in power supply capacitors just like solid state amplifiers. The difference, however, is that solid state amplifiers need capacitors that are able to store tens of thousands of microfarads of charge at their lower operating voltages (+ 14 volts) to equal the amount of energy in joules stored in the power supply capacitors of a vintage tube amplifier charged with only a few hundred microfarads, because of the higher voltages used. The net effect is that the tube amplifier is able to handle musical peaks in a way that solid state equipment can't match. The other reason, more well known reason, is that when tubes reach their maximum output, they clip the signal in a way that is less harsh, with even-order distortions that the human brain finds less grating than the odd order harmonics generated when transistors clip their output signals. What does this have to do with headphones? Well, the HD-600s are capable of very wide dynamic range. When they are fed a clean peak signal from an amplifier, they accurately recreate the musical dynamics present in the signal. With good tube amplification, this makes for hearing some very natural sounding musical peaks on the HD-600s without any harshness.
Regarding the bass, I found the bass reproduction of the HD-600s, while listening to them using the Fisher 400, to be very satisfying and natural. However, I did not hear the same level of power and authority of the lowest octaves, say 50 Hz and below the way I did when listening to the 600s using the Marantz receiver. I believe the reason is that the Fisher rolls off response in the lowest octaves due to the impedance matching output transformers that are part of the output circuitry. These transformers are also responsible for much of the tube sound quality that is so highly prized in these vintage units, so its a trade off but one I would happily make to enjoy the highly musical reproduction of the Fisher 400. Suffice to say that the HD-600s can play much deeper in the bass than the Fisher 400 does, and the HD-600s reproduce all of the bass and other frequencies passing through the Fisher's output tubes and output transformers with ease. It is a joy to listen to the wide-range, dynamic sound of the HD-600s when connected to the Fisher's headphone jack. I guess I could intentionally reverse the leads on the HD-600s to correct the left/right channel reversal of the Fisher's headphone jack. For now, since all of my critical listening with the Fisher tends to be reel to reel tape, I simply reversed the left and right tape inputs to the Fisher.
-Marc
