Inside Mack Amps

A lot has been written about point-to-point wiring, PC boards and the like and many opinions exist as to what is 'better'.  At Mack we believe that we follow a pragmatic approach to the construction of our amps.  Read on to find out how we build our amps and why.

At Mack we use eyelet circuit boards to which components and interconnecting wires are soldered by hand. 

This is not point-to-point (PTP) wiring.  PTP refers to amps whose individual components are soldered to each other without a circuit board although they may utilize terminal strips to hold components. 

Although as you can see in the photo our circuit boards look much like PC boards in that they are precisely laid out and feature silkscreened graphics for easy troubleshooting, but they are not.  PC boards rely on embedded copper traces to interconnect components.  Often, tube sockets and even switches are soldered directly to the PC board.  At Mack only individual components are board mounted; anything attached to the chassis like tube sockets, switches, etc. are connected to the circuit board with hand soldered wires.

So, what's 'better'?  All three methods of building an amp circuit have their pros and cons.  PTP is often suggested as being more rugged and even sometimes it is claimed to have better tone. 

At Mack we do not use PTP wiring because it takes additional labor.  Plus, we do not believe it is more reliable than eyelet boards and we have not been able to confirm for ourselves that it affects tone whatsoever.

We do not use PC boards - even though doing so would REDUCE costs - because we believe that they are inherently more difficult to repair and, when tube sockets are soldered directly to the board, can lead to unreliability because of excessive heat transfer.

We take great care in producing each of our eyelet circuit boards so that they are robust, well laid out, feature silkscreened graphics to minimize the possibility of assembly errors and to make it easier to repair our amps in the field.

We also use high temperature Teflon wires and environmentally friendly lead-free solder.  This costs a bit more, but the relative improvement in reliability and the fact that using lead-free solder is just a good thing to do outweigh the cost penalties.

Each method of wiring an amp has its pros and cons.  Great amps are made using each method.  At Mack we have chosen to use eyelet circuit boards, chassis mounted controls and tube sockets and hand soldering because we believe it is the best compromise between cost, reliability and ease of repair.

Mack Amps

Virtuoso Tone Without The Prima Donna price