A. There is no substitute for listening to determine which amplifier will sound the best with your THIEL speakers. It is our hope that you can personally audition as many products as possible at a THIEL dealer. A good dealer will take the time to find out about your budget, needs, tastes, and musical values--all factors that will influence your decision, and which need to be taken into consideration for the best choice--before showing you equipment.
Also, due to the wide variety of equipment available and the ongoing introduction of new models, it is not possible for us to listen to all available amplifiers on our speakers and, therefore, it is difficult for us to make specific recommendations. Our dealers have greater access to the broad array of products available, and so we will usually refer you to their experience and suggestions in trying new components. However, we can help you by telling you a little about how the speaker performs and you can use this information in your decision making process.
THIEL speakers are extremely accurate and revealing and benefit from use with the the best equipment. Although they do not have to be used with the most expensive components, for the same reasons they reproduce all musical information, they will also reproduce any distortions generated by other components in the chain. Many electronic components such as amplifiers, cables, and cd players have certain sonic colorations that are designed to ameliorate or put a "band-aid" on distortions generated elsewhere in the system.This approach does not fit with our design goal of faithfully translating all of the tonal, spatial, transient, and dynamic information supplied by the amplifier, so sonic accuracy is a very important characteristic when selecting associated equipment.
THIEL speakers have stable impedance characteristics and most have average sensitivity in the 86 to 87dB (@2.8 v-1m) range. The on-wall PowerPoint and in-wall PowerPlane are 89dB, and the MCS1 and CS1.6 are 90dB. (See the power requirements FAQ for more information about recommended power). Because of special circuitry in the crossover, the speakers present a linear impedance, and thus a stable load, to the amplifier. Most of the models have around a 4 ohm nominal impedance and a 2.5 to 3 ohm minimum impedance. Although stable, this lower than average nominal impedance means that a high current amplifier will usually do a better job of driving the speaker. For the larger models, an amplifier should be specified to provide twice the power into 4 ohms as it provides into an 8 ohm load to ensure enough current capacity.
The high current recommendation does not preclude vacuum tube amplifiers from being used with THIEL speakers. With THIEL speakers, connection to the 4 ohm tap of a tube amp is recommended as usually providing the best performance. When using this tap a tube amplifier will need to have about twice the wattage of a high current solid state amp to provide similar current. Just as there is no perfect brand of amplifier, there is no ideal electronic design. Tube amplifiers may excel in some areas of performance that are important to you as a listener. All THIEL models have been used with tube electronics by customers, reviewers, and during exhibits with exceptional results. Again, your dealer's experience and you own auditioning of a variety of amplifiers will guide you to the best choice of amplifier.
We have used a variety of electronics in our listening sessions. We have been fortunate enough to obtain some of the best for these purposes with products from Ayre Acoustics, Boulder, Classe', conrad-johnson, Krell, Mark Levinson, Pass Labs, Theta, and VTL to name a few. There are also more affordable products that we like from Bryston, McCormack, Sim Audio, and Musical Fidelity, as well as high-end "entry level" models from B&K, NAD, and Rotel. There are also many others that we have not heard that certainly could be included on this list.
As we have said, THIEL speakers are designed to reproduce exactly the signal they are given. If the associated equipment has a particular sound or signature, the speaker will reproduce it, whether it's tubes, transistors, or a particular brand. For this reason, we strongly recommend that you work with a qualified THIEL dealer to audition the equipment for yourself.