Longdog Audio P6100M Biamp 2x2 (4 units)
13 lost · Anchored, Artisan, Characterful, PRaT, Reference, Romantic
Against the Anchored brief, the Longdog Audio P6100M Biamp 2x2 (4 units) keeps the slot decisively.
Icon Audio Stereo 25 MkII (KT88)
Integrated amplifier
Relative price
below typical
Among the 59 integrated amplifiers in the catalogue, this one is below typical.
A band places a component against its peers and carries no price. It is deliberately the only price indicator on this page: a second one, measured against a different set, would narrow the two together far enough to give the figure away.
What it is
Icon Audio Stereo 25 MkII — David Shaw's entry-tier valve integrated. "Simplified ST40 MkIII, yet no reduction in quality, this is our best value integrated amplifier" per Icon official. KT88 output (default; tube-rolling to 6L6/EL34/6CA7/KT66/6550 supported). 6SN7/6SL7 double-triode drivers. Hand-wound custom transformers (in Leicester). Hand-wired point-to-point construction (no PCB).
CRITICAL FEATURE: dedicated headphone winding on output transformers. Current production AN brand and budget integrateds rarely match this — typical solid-state headphone output is afterthought. Icon ST25 headphone performance comparable to dedicated valve headphone amps.
Tube-rolling: 6L6/EL34/6CA7/KT66/KT88/6550 selectable via simple self-biasing circuit (no rebias needed for same-type swaps; cross-type swaps require rebias which is documented). Big NOS upgrade potential (Genalex Gold Lion KT88, Mullard EL34 etc).
Excellent first valve amp — Icon's trade-up policy lets owners upgrade ST25 → ST40 → ST60 with credit toward larger Icon models.
Competition record
Assessed against 19 rivals across the sixty systems: it takes the slot in none of its 60 head-to-heads.
Where it gives ground
The dimension the engine names as the weakest link, counted across every head-to-head it lost.
- low-level clarity ×8
- tonal body ×4
- bass control ×1
Who it comes up against
NVA S80 Stereo
8 lost · Artisan, Cavity-Native, Characterful, Intimate, PRaT, Reference, Romantic, Silent Path
Against the Characterful brief, the NVA S80 Stereo keeps the slot decisively.
Audiolab 9000P
5 lost · Anchored, Characterful, PRaT, Romantic, Silent Path
Against the Characterful brief, the Audiolab 9000P keeps the slot decisively.
Sugden ANV 50
4 lost · BBC Sound, Twin Arms
Against the Twin Arms brief, the Sugden ANV 50 keeps the slot decisively.
On its own merits the Icon Audio Stereo 25 MkII (KT88) is the weaker integrated amplifier for that brief.
It sits well below the share of the budget this brief aims at the integrated amplifier position.
Leema Hydra II
4 lost · Cavity-Native, Characterful, Romantic
Against the Cavity-Native brief, the Leema Hydra II keeps the slot decisively.
NVA S300 Stereo (Artisan)
4 lost · Artisan, Cavity-Native, Intimate, Reference
Against the Intimate brief, the NVA S300 Stereo (Artisan) keeps the slot decisively.
Icon Audio Stereo 30 SE (KT150)
3 lost · Vocals-First
Against the Vocals-First brief, the Icon Audio Stereo 30 SE (KT150) keeps the slot clearly.
With the Tom Evans Groove+ SRX MkII, the pairing gives up most on tonal body.
On its own merits the Icon Audio Stereo 25 MkII (KT88) is the weaker integrated amplifier for that brief.
It sits well below the share of the budget this brief aims at the integrated amplifier position.
fluid and naturalWhat Hi-Fi? 2008 (Stereo 25 MkI)
Audio Note P1 SE
3 lost · Intimate, Silent Path
Against the Silent Path brief, the Audio Note P1 SE keeps the slot decisively.
EAR Yoshino V12
3 lost · BBC Sound, Vocals-First
Against the BBC Sound brief, the EAR Yoshino V12 keeps the slot decisively.
With the Rega Aura Reference MC, the pairing gives up most on low-level clarity.
With the Falcon LS3/5a Gold Badge, the pairing gives up most on low-level clarity.
On its own merits the Icon Audio Stereo 25 MkII (KT88) is the weaker integrated amplifier for that brief.
fluid and naturalWhat Hi-Fi? 2008 (Stereo 25 MkI)
Exposure XM9 Biamp 2x2 (4 units)
3 lost · Artisan, PRaT, Reference
Against the Artisan brief, the Exposure XM9 Biamp 2x2 (4 units) keeps the slot decisively.
EAR Yoshino 890
2 lost · Intimate
Against the Intimate brief, the EAR Yoshino 890 keeps the slot decisively.
Chord ULTIMA 6
1 lost · Cavity-Native
Against the Cavity-Native brief, the Chord ULTIMA 6 keeps the slot decisively.
Longdog Audio P6100M (pair)
1 lost · Anchored
Against the Anchored brief, the Longdog Audio P6100M (pair) keeps the slot decisively.
Exposure 3510
1 lost · Twin Arms
Against the Twin Arms brief, the Exposure 3510 keeps the slot decisively.
On its own merits the Icon Audio Stereo 25 MkII (KT88) is the weaker integrated amplifier for that brief.
Sugden A21 Signature
1 lost · BBC Sound
Against the BBC Sound brief, the Sugden A21 Signature keeps the slot decisively.
With the Naim NVC TT MM/MC, the pairing gives up most on low-level clarity.
With the Harbeth P3ESR XD2, the pairing gives up most on low-level clarity.
On its own merits the Icon Audio Stereo 25 MkII (KT88) is the weaker integrated amplifier for that brief.
Rega io
1 lost · Twin Arms
Against the Twin Arms brief, the Rega io keeps the slot by a whisker.
On its own merits the Icon Audio Stereo 25 MkII (KT88) is the weaker integrated amplifier for that brief.
Leak Stereo 230
1 lost · Vocals-First
Against the Vocals-First brief, the Leak Stereo 230 keeps the slot by a whisker.
On its own merits the Icon Audio Stereo 25 MkII (KT88) is the weaker integrated amplifier for that brief.
Creek 4040A
1 lost · BBC Sound
Against the BBC Sound brief, the Creek 4040A keeps the slot clearly.
With the Falcon Q7 Complete@Home, the pairing gives up most on bass control.
On its own merits the Icon Audio Stereo 25 MkII (KT88) is the weaker integrated amplifier for that brief.
wasn't as tight as good solid-stateSoundStage! Access 2010 (MkI)
Quad Artera Stereo
1 lost · Silent Path
Against the Silent Path brief, the Quad Artera Stereo keeps the slot decisively.
What the reviewers said
KT88 push-pull integrated, classic UK valve voicing Icon Audio Stereo 25 MkII KT88 positioning· Harmonic texture
fluid and natural What Hi-Fi? 2008 (Stereo 25 MkI)· Tonal body
clarity is deeply impressive What Hi-Fi? 2008 (MkI)· Presence & articulation
wasn't as tight as good solid-state SoundStage! Access 2010 (MkI)· Bass control
loses a little composure What Hi-Fi? 2008 (MkI)· Dynamic coherence
How it scores
Clarity
- Electrical noise floor 80 from specification
Voice
- Tonal body 74 from listening evidence
- Presence & articulation 74 from listening evidence
- Harmonic texture 71 from listening evidence
Bass
- Bass control 66 from listening evidence
- Physical impact 59 from specification
- Bass extension 59 from specification
LowerVolume
- Low-level noise floor 80 from specification
- Micro-dynamic resolution 72 from specification
- Tonal consistency 72 from specification
Specifications
| power 8ohm w | 30.0 |
|---|---|
| power 4ohm w | 30.0 |
| power class | AB |
| damping factor | 8.0 |
| line inputs | 3 |
| line input sensitivity mv | 250.0 |
| line input impedance kohm | 100.0 |
| has phono | False |
| phono mm | False |
| phono mc | False |
| pre out | False |
| pre power separable | none |
| internal bass management | none |
| headphone out | True |
| frequency response hz | 20/20000 |
| snr db | 90.0 |
| thd pct | 0.2 |
| dimensions mm | 340/210/340 |
| weight kg | 17.0 |
| power consumption w | 100 |
| integrated dac | False |
| digital inputs | 0 |
| notes |