Appellant, Norman Christopher Hart, was convicted in the Christian Circuit Court for the first-degree rape of a thirteen-year-old female, L.W., and was sentenced to ten years imprisonment. The Court of Appeals affirmed his conviction and this Court thereafter granted discretionary review. For the reasons set forth herein, we affirm the decision of the Court of Appeals.
At trial, Lucy Davis, a DNA expert with the Kentucky State Police Laboratory, testified, without objection, via closed circuit camera from the KSP crime laboratory in Frankfort. During the Commonwealth’s direct examination, Davis testified that she analyzed samples obtained from the sexual assault kit administered to L.W. and determined that the male DNA extracted from the vaginal swab matched the DNA profile of Appellant in four out of five polymorphic genetic low sites. Davis stated that the statistical probability of finding this particular DNA profile in the African-American population was 1 in 125 million.
On cross-examination, Davis described the analysis of the evidence as a two-step process. First, an autoradiogram is viewed to determine if the two DNA profiles align visually. Davis explained that an autoradiogram is an x-ray film that has a banding pattern which is part of the DNA profile. Davis then described the second step of the process, referred to as a calculated match, which generates a computer printout representing the approximate base pair size of each piece of DNA. The camera transmission was insufficient to allow Davis to clearly display the auto-radiogram and computer printout to the jury during her testimony.
At a bench conference, defense counsel inquired about having the autoradiogram and computer printout introduced into evidence. Although the Commonwealth offered to obtain copies by fax, defense counsel objected on the grounds that the original documents were the best evidence. The trial court ruled that Davis’ testimony was, in fact, the best evidence and that there was no need to admit what the trial court considered demonstrative evidence and the work product of the expert.
On appeal, the Court of Appeals upheld the trial court’s ruling. However, the Court of Appeals concluded that the auto-radiogram and the computer printout were both admissible and relevant, but unavailable since the trial was held in Hopkins-ville and Davis testified from Frankfort with the autoradiogram and computer printout in her possession. The Court of Appeals further noted that Appellant neither objected to Davis’ testimony via closed circuit television, nor moved for a continuance so that the original documents could be obtained.
We agree with the Court of Appeals opinion only insofar as the computer printout and autoradiogram were both admissible and relevant evidence. KRE 705 permits cross-examination to disclose the “underlying facts or data” supporting an expert’s opinions and inferences, and the excluded forensic evidence is of a type generally admissible at trial. However, we are compelled to affirm Appellant’s conviction because, as we will explain, this matter has not been properly preserved for appellate review.
KRE 103 sets forth the procedure for preserving claims of error relat-*483mg to evidentiary rulings which exclude evidence:
(a) Effect of erroneous ruling. Error may not be predicated upon a ruling which admits or excludes evidence unless a substantial right of the party is affected; and
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(2)Offer of Proof. In case the ruling is one excluding evidence, upon request of the examining attorney, the witness may make a specific offer of his answer to the question.
(b) Record of offer and ruling. The court may add any other or further statement which shows the character of the evidence, the form in which it was offered, the objection made, and the ruling thereon. It may direct the making of an offer in question and answer form.
RCr 9.52 tracks the language of KRE 108, and although both are “couched in terms of preserving oral testimony,” they apply equally to questions regarding the introduction of real evidence. Garrett v. Commonwealth, Ky., 48 S.W.3d 6, 15 (2001).
These rules are not mere technicalities or traps for the unwary. As noted by the 1992 Commentary to the Kentucky Rules of Evidence, offers of proof and avowals serve to:
(i) offer counsel a fair opportunity to address admissibility issues and take corrective measures when feasible; (ii) provide the trial judge with sufficient information to assure correct rulings on the admission or exclusion of evidence; and (in) provide a record, sufficient for an appellate court to review decisions concerning the admissibility of evidence. These objectives are served, generally speaking, by requiring that a proper “offer of proof’ be made when attempting to introduce evidence....
1992 Commentary to KRE 103 (emphasis added).
In the present matter, we must determine whether the trial court’s erroneous exclusion of forensic evidence was prejudicial or merely harmless. In order to do so, the record must contain sufficient information for this Court to assess the harm stemming from the trial court’s ruling. “Prejudice will not be presumed from a silent record.” Baze v. Commonwealth, Ky., 965 S.W.2d 817, 824 (1997), citing Walker v. Commonwealth, Ky., 476 S.W.2d 630, 631 (1972).
The record here is certainly not silent, for the video transcript reveals the general nature of the excluded evidence. The dark bands on the autoradiogram are visible, and some writing can be detected on the computer printout. However, the remote closed-circuit transmission was of such poor quality that no details of either item are visible, despite the expert’s attempts to display them for the jury.
A reviewing court requires more than the general substance of excluded evidence in order to determine whether a defendant has suffered prejudice. In Partin v. Commonwealth, Ky., 918 S.W.2d 219 (1996), we held that a description of proposed testimony by defense counsel was insufficient to preserve an alleged error in the exclusion of evidence for review. “Counsel’s version is not enough. A reviewing court must have the words of the witness.” Id. at 223. More recently, in Commonwealth v. Ferrell, Ky., 17 S.W.3d 520 (2000), we reaffirmed our holding in Partin, stating: “a party must offer an avowal by the witness in order to preserve for appellate review an issue concerning the exclusion of evidence.” Id. at 525.
A decision in favor of Appellant would require us to assume that there was a substantial possibility the jury would have reached a different verdict if the evidence had not been excluded. Taylor v. Com*484monwealth, Ky., 995 S.W.2d 355 (1999); Commonwealth v. McIntosh, Ky., 646 S.W.2d 43 (1983). We decline to engage in such guesswork without the actual evidence before us. “Without an avowal, or a crystal ball, reviewing courts can never know with any certainty what a given witness’s response to a question would have been if the trial court had allowed them to answer. Appellate courts review records; they do not have crystal balls.” Ferrell, supra, at 525 n. 10.
In order to preserve this issue for appellate review, Appellant needed only to request that the excluded items be entered into the record by offer or avowal. KRE 103; RCr 9.52. The distance between Hopkinsville and Frankfort is such that a one-day continuance would have allowed more than sufficient time for defense counsel to obtain the documents. A refusal by the trial court to allow this offer would have constituted reversible error, since a reviewing court would have no means by which it could adjudicate whether the exclusion of evidence was prejudicial. Jones v. Commonwealth, Ky., 623 S.W.2d 226, 227 (1981); Powell v. Commonwealth, Ky., 554 S.W.2d 386, 390 (1977); Perkins v. Commonwealth, Ky.App., 834 S.W.2d 182 (1992).
Because counsel failed to take the necessary steps to preserve the autoradiogram and computer printout by avowal, we have no means to discern from the record whether Appellant was prejudiced by the trial court’s erroneous exclusion of this evidence. Thus the matter is not preserved for our review.
Therefore, both the judgment and sentence of the Christian Circuit Court are affirmed.
LAMBERT, C.J., GRAVES, KELLER, and WINTERSHEIMER, J.J. concur. COOPER, J., dissents in a separate opinion in which JOHNSTONE, and STUMBO, J.J. join.