These tubes were tested with a calibrated B and K 707 tube tester. The following tests were made:
DYNAMIC MUTUAL CONDUCTANCE: Mutual conductance is the ratio of the change in the plate current that results from a small change in grid voltage. Virtually all tubes (except rectifiers and diodes), are some type of amplifier. The most important characteristic of most tubes is its ability to amplify. Thus this test is the most accurate and all inclusive test that can be made on tube.
Mutual Conductance Scale:
0 to 55: Weak (tube may function in some circuits, but it is near the end of its life)
55 to 65: ? (tube will function in many circuits, but not operating optimumally)
65 or Higher: GOOD range
GAS TEST: Tubes that are found to be ?gassy? are rejected
GRID EMISSION TEST: Each tube is tested for grid emission and tubes that fail this test are rejected unless otherwise noted.
SHORTS TEST: The test for shorts between elements of the tube is made to a sensitivity of approximately 1 megaohm. Tubes with shorted elements are rejected
LIFE TEST: This test generally gives you an indication of the probable useful life of a tube. The test reduces the heater voltage by 10 to 15% and tests Gm. If the Gm of the tube does not drop significantly with the reduced heater voltage, this is a good indication that the tube will give you trouble-free service over time.
Due to items lost or damaged in shipping, any item over $50.00 in
cost will require delivery confirmation and insurance for the sale
amount.
It is unfortunate that this is necessary but experience has proven it is well worth the small extra cost. We apologize for this, but it is for the good of all involved.
TERMS:
All listings are plus shipping unless noted. 7.00% sales tax added
to all In-state destinations. This unit is guaranteed to be in "as
described" working condition (unless otherwise noted) upon arrival and
has a 60 day limited warranty, baring any abuse.
15% restocking fee on all returns unless defective or "not as described"
SHIPPING:
We ship internationally on smaller items . Domestic packages are
shipped via Fed Ex. All international shipping quotes will include
insurance and delivery confirmation. Shipping charges reflect actual
cost of shipping, plus a nominal fee for packaging materials.
INSURANCE:
International shipments to countries that do not allow insurance,
buyer assumes FULL RESPONSIBILITY for the safe shipment of their
packages. Sound Ideas cannot provide refunds or compensation for
packages shipped without shipping insurance. All shipping quotes for
packages shipped includes insurance.
RETURNS:
Any item may be returned within 15 days for a full refund of the
purchase price, not including shipping, unless otherwise stated in the
ad.
It must arrive back at our store in the same condition as sent. 15% restocking fee on new items that were opened.
International purchases need to be returned with incoming custom's
duty prepaid, if any.
Any postage or import duty that is due upon
arrival will be deducted from the refund.
15% restocking fee also on all returns, unless defective or "not as described."
Thank-you for your time and interest!
About Us
History
In 1977, Sound Ideas opened its doors in Gainesville, Florida and very quickly established itself as the premier dealer for high-end audio systems. Over the years, we naturally progressed into home theater, distributed audio/video, lighting control, structured wiring, security and complete automation systems. Today, we stand as a custom hybrid-retailer that provides a ?Boutique Style? shopping experience for the best audio and video products on the market. We are North Florida?s leader in residential and commercial integration ? positioned on the cutting edge of technology while meeting the ever changing needs of our customers.
Employees
Sound Ideas' staff of 18 employees
are there to help you in every situation. We have knowledgeable sales
associates, system designers, technicians, programmers, repair
technicians, and service personnel on hand to meet your every needs!
