Antique Sound Lab Monsoon
Original Design
Reference Upgrade
by Response Audio

Response Audio has introduced the Reference Series upgrade for the Antique Sound Lab 100 watt tube mono bloc amplifiers.

After performing Extreme upgrades to nearly 45 pair of Hurricanes and Monsoons and dozens of Signature Hurricanes, we were continuously asked to come out with an upgrade falling somewhere in between. To make things much simpler, we now have all the upgrade options on this one page.

All our upgrades addresses every aspect of these amplifiers. The power supply, input and phase splitter circuit as well as the main output circuitry are all gone through thoroughly.

If you are interested in upgrades to the MKII Monsoon (now housed in the original Hurricane chassis) please visit our Hurricane Upgrade Page.

What's Included

** Coupling capacitors installed in the signal path coupling stages (x8 pieces) as well as the input coupling caps in the input circuit (x1 pieces). The capacitors are mounted using a high quality double sided adhesive tape as well as being secured with zip-ties to eliminated vibration.

** Various capacitors are available depending on your personal preference.

• VH Audio V-Cap TFTF or CUTF

• Clarity Cap MR Series (Minimal Resonance) capacitors

• Mundorf Silver/Oil/Gold

• Mundorf Silver/Oil
  
  ** Dale/Vishay 3W resistors are used for the grid stop applications. x8 pieces
  All grid stop resistors are mounted directly to the grid pin of each power tube eliminating all unnecessary wiring. It is a common practice to mount the body of grid stopper resistors as close to the tube grid as possible. Many tube amp manufacturers do not utilize this practice. All grid stop resistors are then mounted directly to the leads of the coupling capacitors and all leads are cut to minimum length.
  
  ** Dale/Vishay resistors are used for the screen grid applications. x16 pieces
  
  ** High quality 3 watt resistors used in cathode ground locations of all power tubes  x8 pieces
  
  ** Dale/Vishay 1 watt 1% non-magnetic resistors used throughout the signal path. The signal leads of these resistors are shortened to the shortest lengths possible and all exposed leads are covered with heat shrink to help eliminate vibration and protect against shorts.
  
  ** Dale/Vishay 1 watt, 1% resistors are used in the bias stage in series with the coupling capacitors. These resistors are mounted in series with the coupling capacitors and then into the bias stage circuit boards. Again, we keep all signal wiring as short as possible.
  
  ** All exposed resistor leads throughout these amplifiers have heatshrink applied to help reduce mechanical vibration as well as preventing circuit shorts.
  
  ** The grounding layout is reworked to provide a the best possible results with a dead quite background and lower noise floor.
  
  ** All power supply capacitors are bypassed with Clarity Cap SA Series capacitors. Each power supply filter capacitor receives its own bypass unit. Total of 4 bypass capacitors depending on model
  
  ** "Ultra Fast - Soft Recovery" diodes are utilized in the rectifying stage of the power supply. The diodes are mounted directly to the capacitors of the power supply.
  
  ** High quality solid core shielded internal signal wire. x6 feet
  Your choice of solid silver or solid copper
  We also apply a full shield to this wire to also further reduce any possible noise.
  
  ** RCA input jacks are high quality silver Cardas RCA jacks.
  
  ** RoHS compliant silver solder used throughout
  
  ** Bench tested for 2 hours
  
  ** Minimum 12 hour burn in
  
  ** Labor : 12+ hours per pair
  
  ** Pricing: does not include shipping to and from our New York facility.

Price

A popular combination of capacitors is to use the V-Cap TFTF capacitors for the main signal capacitors with a V-Cap CUTF for the input coupling capacitor. If running balanced inputs, the input coupling capacitor is NOT utilized in the circuit.

Ordering

Please contact us to discuss turnaround times which are based on our current work load.

A minimum 60% down payment is required at time of order with the balance due prior to shipping.

This process will also help aid you in diagnosing a bad tube.