|Last Update: November 04, 2000 at 09:18:14||IP Address: 22.214.171.124|
|Amplifier:||Sugden A21a pure class A solidstate with a history.|
Rise time 1.5u seconds
25W into 8ohm
THD 1.2% @ 1kHz, mainly 2nd harmonics.
Damping @ 50Hz/8ohm = 40
(Read about British class A audio amplifier history & the A21a writeup at www.audiosynergy.co.uk/a21a.htm)
|Preamplifier (or None if Integrated):||Sugden Signature 41|
Remote volume control.
|Speakers:||Martin Logan Aerius hydrid system, 2-way,100W. 40~22kHz -+3dB|
LF = 8" woofer.
HF = single curved electrostatic panel
|CD Player/DAC:||Sugden Audition CDP (Yr1999)|
|Turntable/Phono Stage:||Thorens 125, SME3012, FR mc cartridge|
All >25 years old
|Other Source(s):||AR antique tuner PLL circuitry, string/pulley dial pointer.|
|Speaker Cables/Interconnects:||Spkr cables Monster M1Mk2|
IC cables (CDP to amp) X1.5-0.8m diy design adapted from TNT website, thanks to Thorsten Loesch.
IC cables (Pre to Pwr amp) Monster 1000Mk3-0.5m
|Other (Power Conditioner, Racks etc.):||Target 6 tiered rack|
|Tweaks:||(1)A21a like all pure classA amps dissipates lots of heat even at low/normal sound level. Problem solved by clamping on (externally), additional stock heatsink on the non-draughty side(left) of amp. making amp chassis "touchable" and almost equalize the temperature of LH&RH heatsinks to ensure both channels operate on near equal terms. Not so beautiful to look at, but effective by sounding right.|
(2) Constructed both X-1.5 & X-3 versions of T. Loesch (TNT)diy IC cables. Prefers the medium capacitance (=< 166pF) X-1.5, 0.8m;the designer's 1m version (cap. 200pF) may be a little bit slower than my chosen 0.8m length. It's a very exciting DIY project for me & it sounds better without the the outer shrink sleeve! I highly recommend this tweak to the DIY savvy, being quite a pain to construct is well worth it. Perform its best installed between my cdp/preamp, the mid/high frequencies are sizzling, fast & detailed and not bright on majority of my cd's. The bass note is full and definitive. Manuf'r customised Monster 1000Mk3-0.5m IC between preamp&pwramp provides a pleasant 3D soundstage that highend Monster cables are capable of creating.
(3)Constructed a power supply facility using Belden shielded 3cx14awg cables. The shield is extended to each equipment, even through the metalcase of the MEM multiple socket outlets. Two-pole switched s/o completely isolates each gear which is turnoff when not in use. Good bass extension with this tweak mainly due to larger conductor good for pwr amp.
|Room Size (LxWxH):||11' x 14' x 10'|
|Room Comments/Treatments:||Semi-solid wood panel on 2 sides,teak parquet floor, heavy rug, normal furnishing, quite dead acoustically.|
|Music Preferences and Comments:|
|Music Used (Genre/Selections):||New jazz, world, classical, mostly audiophile & selected well recorded standard cds.|
|System Goals/Comments:||1) To acquire a higher powered amp of similar or better performance, probably another pure class A solid state or a SET tube amp. Lunatic obsession with class A operating mode amp quite incurable in that.|
2) To investigate scientifically, the true benefits of powerchords/power conditioning in highend. Findings so far is that large conductor size 14awg upwards provide better bass extension. Also trying out EMI/RFI filters on cdp because i believe cdp's are the culprit contributor of EMI/RFI back into the power system to which it is connected!!
|System Strengths:||Paired with the M'logan electrostatics, the Sugden electronics are very fast, has impressive frequency range & accuracy, very believable intimate soundstage jazz reproduction especially acoustic instruments at normal & low sound level, hard to beat sensation. This lunatic can "hear" extension of frequencies beyond the theoretical 20kHz. Got to thank Sugden & M'Logan that their excellent designs are able to complement one another.|
|System Weaknesses:||Slight roughness noticeable if played at very high sound level may be due to a21's modest power rating, seldom attempt to do that anyway.|
|Video/HT System: None|
|Other Interests/Hobbies/Occupation:||An audiophile for the last 30 years besides Fishing/Tennis/Reading.|
Occ. Instrument engineer.